Equity Commonwealth - Annual Report: 2013 (Form 10-K)

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PART IV

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549

FORM 10-K

Commission file number 1-9317

COMMONWEALTH REIT
(Exact Name of Registrant as Specified in Its Charter)

Registrant's Telephone Number, Including Area Code: 617-332-3990

Securities registered pursuant to Section 12(b) of the Act:

           Securities registered pursuant to Section 12(g) of the Act: None

           Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ý    No o

           Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o    No ý

           Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

           Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes ý    No o

           Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ý

           Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):

           Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o    No ý

           The aggregate market value of the voting common shares of beneficial ownership, $0.01 par value, or common shares, of the registrant held by non-affiliates was $2.7 billion based on the $23.12 closing price per common share on the New York Stock Exchange on June 28, 2013. For purposes of this calculation, an aggregate of 372,373 common shares held directly by, or by affiliates of the trustees and the officers of the registrant, plus 250,000 common shares held by Senior Housing Properties Trust, have been included in the number of common shares held by affiliates.

           Number of the registrant's common shares outstanding as of February 24, 2014: 118,403,105.

DOCUMENTS INCORPORATED BY REFERENCE

           Certain Information required by Items 10, 11, 12, 13 and 14 of Part III of this Annual Report on Form 10-K is incorporated herein by reference to our to be filed definitive Proxy Statement for the 2014 Annual Meeting of Shareholders scheduled to be held on June 13, 2014, or our definitive Proxy Statement.

WARNING CONCERNING FORWARD LOOKING STATEMENTS

        THIS ANNUAL REPORT ON FORM 10-K CONTAINS STATEMENTS THAT CONSTITUTE FORWARD LOOKING STATEMENTS WITHIN THE MEANING OF THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995 AND OTHER SECURITIES LAWS. ALSO, WHENEVER WE USE WORDS SUCH AS "BELIEVE", "EXPECT", "ANTICIPATE", "INTEND", "PLAN", "ESTIMATE" OR SIMILAR EXPRESSIONS, WE ARE MAKING FORWARD LOOKING STATEMENTS. THESE FORWARD LOOKING STATEMENTS ARE BASED UPON OUR PRESENT INTENT, BELIEFS OR EXPECTATIONS, BUT FORWARD LOOKING STATEMENTS ARE NOT GUARANTEED TO OCCUR AND MAY NOT OCCUR. FORWARD LOOKING STATEMENTS IN THIS REPORT RELATE TO VARIOUS ASPECTS OF OUR BUSINESS, INCLUDING:

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THE RESULTS OF PENDING, THREATENED OR FUTURE LEGAL AND ARBITRATION PROCEEDINGS, INCLUDING CLAIMS REGARDING THE PUBLIC OFFERING AND SALE OF 34,500,000 OF OUR COMMON SHARES COMPLETED ON MARCH 5, 2013, THE PUBLIC OFFERING AND SALE OF 9,950,000 COMMON SHARES OF GOVERNMENT PROPERTIES INCOME TRUST, OR GOV, THAT WE PREVIOUSLY OWNED COMPLETED ON MARCH 15, 2013 AND MATTERS RELATED TO THE RELATED FUND MANAGEMENT, LLC AND CORVEX MANAGEMENT LP , OR TOGETHER, RELATED/CORVEX, SOLICITATION OF CONSENTS TO REMOVE OUR ENTIRE BOARD OF TRUSTEES, WITHOUT CAUSE, AND, IF SUCCESSFUL, PROXIES TO ELECT THEIR SLATE OF NOMINEES AS REPLACEMENT TRUSTEES,



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POSSIBLE DISRUPTION OR HARM TO OUR BUSINESS AS A RESULT OF THE RELATED/CORVEX CONSENT SOLICITATION OR OTHER ACTIVITIES BY RELATED/CORVEX,



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POSSIBLE DISRUPTION OR HARM TO OUR BUSINESS OR A MATERIAL CHANGE IN OUR FINANCIAL POSITION AS A RESULT OF THE REMOVAL OF OUR BOARD OF TRUSTEES OR A CHANGE IN OUR MANAGEMENT IF THE RELATED/CORVEX CONSENT SOLICITATION IS SUCCESSFUL,



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OUR POLICIES AND PLANS REGARDING INVESTMENTS, FINANCINGS AND DISPOSITIONS,



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THE FUTURE AVAILABILITY OF BORROWINGS UNDER OUR REVOLVING CREDIT FACILITY,



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OUR ABILITY TO RAISE EQUITY OR DEBT CAPITAL,



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THE FUTURE AMOUNT OF LEASING ACTIVITY AND OCCUPANCY RATES AT OUR PROPERTIES,



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THE FUTURE RENT RATES WE WILL BE ABLE TO CHARGE AT OUR PROPERTIES,



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THE COSTS WE MAY INCUR TO LEASE SPACE IN OUR PROPERTIES,



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OUR ABILITY TO PAY DISTRIBUTIONS TO OUR SHAREHOLDERS AND THE AMOUNTS OF SUCH DISTRIBUTIONS,



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THE CREDIT QUALITIES OF OUR TENANTS,



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THE LIKELIHOOD THAT OUR TENANTS WILL PAY RENT, RENEW LEASES, ENTER INTO NEW LEASES OR BE AFFECTED BY CYCLICAL ECONOMIC CONDITIONS,



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OUR ACQUISITIONS AND SALES OF PROPERTIES,



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OUR ABILITY TO COMPETE FOR ACQUISITIONS AND TENANCIES EFFECTIVELY,



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OUR ABILITY TO PAY INTEREST ON AND PRINCIPAL OF OUR DEBT,

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OUR EXPECTATION THAT WE WILL BENEFIT FINANCIALLY BY PARTICIPATING IN AFFILIATES INSURANCE COMPANY, OR AIC, WITH REIT MANAGEMENT & RESEARCH LLC, OR RMR, AND COMPANIES TO WHICH RMR PROVIDES MANAGEMENT SERVICES,



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OUR EXPECTATION THAT WE WILL BENEFIT FINANCIALLY FROM OUR OWNERSHIP INTEREST IN SELECT INCOME REIT, OR SIR,



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OUR TAX STATUS AS A REAL ESTATE INVESTMENT TRUST, OR REIT, AND



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OTHER MATTERS.

        OUR ACTUAL RESULTS MAY DIFFER MATERIALLY FROM THOSE CONTAINED IN OR IMPLIED BY OUR FORWARD LOOKING STATEMENTS AS A RESULT OF VARIOUS FACTORS. FACTORS THAT COULD HAVE A MATERIAL ADVERSE EFFECT ON OUR FORWARD LOOKING STATEMENTS AND UPON OUR BUSINESS, RESULTS OF OPERATIONS, FINANCIAL CONDITION, NET OPERATING INCOME, FUNDS FROM OPERATIONS, OR FFO, NORMALIZED FUNDS FROM OPERATIONS, OR NORMALIZED FFO, CASH FLOWS, LIQUIDITY AND PROSPECTS INCLUDE, BUT ARE NOT LIMITED TO:

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THE RESULTS OF THE PENDING RELATED/CORVEX CONSENT SOLICITATION,



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THE RESULTS ACHIEVED IN OUR PENDING LITIGATION OR ARBITRATION PROCEEDINGS,



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THE IMPACT OF CHANGES IN THE ECONOMY AND THE CAPITAL MARKETS ON US AND OUR TENANTS,



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COMPETITION WITHIN THE REAL ESTATE INDUSTRY, PARTICULARLY IN THOSE MARKETS IN WHICH OUR PROPERTIES ARE LOCATED,



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ACTUAL AND POTENTIAL CONFLICTS OF INTEREST WITH OUR MANAGING TRUSTEES, SIR, GOV, SENIOR HOUSING PROPERTIES TRUST, OR SNH, RMR, AIC AND THEIR RELATED PERSONS AND ENTITIES,



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COMPLIANCE WITH, AND CHANGES TO, FEDERAL, STATE AND LOCAL LAWS AND REGULATIONS, ACCOUNTING RULES, TAX LAWS AND SIMILAR MATTERS,



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LIMITATIONS IMPOSED ON OUR BUSINESS AND OUR ABILITY TO SATISFY COMPLEX RULES IN ORDER FOR US TO QUALIFY AS A REIT FOR U.S. FEDERAL INCOME TAX PURPOSES, AND



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ACTS OF TERRORISM, OUTBREAKS OF SO CALLED PANDEMICS OR OTHER MANMADE OR NATURAL DISASTERS BEYOND OUR CONTROL.

FOR EXAMPLE:

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IF OUR ENTIRE BOARD OF TRUSTEES IS REMOVED AS A RESULT OF THE RELATED/CORVEX CONSENT SOLICITATION, SUCH REMOVAL MAY, AMONG OTHER THINGS, CAUSE SEVERAL ADVERSE CONSEQUENCES TO OUR CONTINUED OPERATIONS, INCLUDING: (I) DEFAULT OF OUR REVOLVING CREDIT FACILITY AND TERM LOAN AGREEMENTS PERMITTING OUR LENDERS TO ACCELERATE REPAYMENTS, (II) ACTIVATION OF EQUITY CONVERSION RIGHTS UNDER OUR SERIES D CUMULATIVE CONVERTIBLE PREFERRED SHARES, (III) POSSIBLE DEFAULTS OF CERTAIN OF OUR MORTGAGE DEBT OBLIGATIONS, (IV) POSSIBLE CROSS DEFAULTS OF OUR OTHER DEBT OBLIGATIONS INCLUDING OUR APPROXIMATELY $1.4 BILLION OF UNSECURED NOTES, (V) FAILURE TO MEET NEW YORK STOCK EXCHANGE, OR NYSE, AND SECURITIES AND EXCHANGE COMMISSION, OR THE SEC, REQUIREMENTS TO ALLOW OUR SECURITIES TO CONTINUE TO BE PUBLICLY TRADED, AND (VI) OUR INABILITY

TO AUTHORIZE THE PAYMENT OF FUTURE DISTRIBUTIONS TO OUR COMMON AND PREFERRED SHAREHOLDERS,

•

WE ARE CURRENTLY INVOLVED IN A NUMBER OF LITIGATION AND ARBITRATION PROCEEDINGS. THE RESULTS OF SUCH PROCEEDINGS ARE DIFFICULT TO PREDICT AND WE CAN PROVIDE NO ASSURANCES REGARDING SUCH RESULTS. EVEN IF WE ARE SUCCESSFUL IN SUCH LEGAL PROCEEDINGS, THE PENDENCY AND CONDUCT OF SUCH PROCEEDINGS MAY BE EXPENSIVE AND DISTRACTING TO OUR MANAGEMENT, AND COULD BE DISRUPTIVE TO OUR OPERATIONS OR CAUSE US TO EXPERIENCE LOSSES,



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THE CURRENT UNEMPLOYMENT RATE IN THE UNITED STATES MAY BECOME WORSE IN THE FUTURE. SUCH CIRCUMSTANCES MAY REDUCE DEMAND FOR LEASING OFFICE SPACE. IF THE DEMAND FOR LEASING OFFICE SPACE REMAINS OR BECOMES FURTHER DEPRESSED, WE MAY BE UNABLE TO RENEW LEASES WITH OUR TENANTS AS LEASES EXPIRE OR ENTER INTO NEW LEASES AT RENTAL RATES AS HIGH AS EXPIRING RATES, AND OUR FINANCIAL RESULTS MAY DECLINE,



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SOME OF OUR TENANTS MAY NOT RENEW EXPIRING LEASES, AND WE MAY BE UNABLE TO LOCATE NEW TENANTS TO MAINTAIN OR INCREASE THE HISTORICAL OCCUPANCY RATES OF, OR RENTS FROM, OUR PROPERTIES,



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OUR COSTS FOR TENANT IMPROVEMENTS AND LEASING COMMISSIONS MAY CONTINUE AT HIGH RATES OR EVEN INCREASE, AND ANY INVESTMENTS WE MAY MAKE IN AN ATTEMPT TO INCREASE OR MAINTAIN OUR OCCUPANCIES MAY NOT SUCCEED,



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OUR ABILITY TO MAKE FUTURE DISTRIBUTIONS DEPENDS UPON A NUMBER OF FACTORS, INCLUDING OUR FUTURE EARNINGS, THE CAPITAL COSTS WE INCUR TO LEASE OUR PROPERTIES AND OUR RECEIPT OF DISTRIBUTIONS FROM SIR UNLESS AND UNTIL WE SELL OUR SIR SHARES. WE MAY BE UNABLE TO MAINTAIN OUR CURRENT RATE OF DISTRIBUTIONS ON OUR COMMON AND PREFERRED SHARES, AND FUTURE DISTRIBUTIONS MAY BE SUSPENDED,



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CONTINUED AVAILABILITY OF BORROWINGS UNDER OUR REVOLVING CREDIT FACILITY IS SUBJECT TO OUR SATISFYING CERTAIN FINANCIAL COVENANTS AND MEETING OTHER CUSTOMARY CREDIT FACILITY CONDITIONS,



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ACTUAL COSTS UNDER OUR REVOLVING CREDIT FACILITY WILL BE HIGHER THAN LIBOR PLUS A PREMIUM BECAUSE OF OTHER FEES AND EXPENSES ASSOCIATED WITH OUR REVOLVING CREDIT FACILITY,



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INCREASING THE MAXIMUM BORROWINGS UNDER OUR REVOLVING CREDIT FACILITY AND TERM LOAN IS SUBJECT TO OUR OBTAINING ADDITIONAL COMMITMENTS FROM LENDERS, WHICH MAY NOT OCCUR,



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OUR ABILITY TO GROW OUR BUSINESS AND INCREASE OUR DISTRIBUTIONS DEPENDS, IN PART, UPON OUR ABILITY TO BUY PROPERTIES AND LEASE THEM FOR RENTS, LESS PROPERTY OPERATING EXPENSES, THAT EXCEED OUR CAPITAL COSTS. WE MAY BE UNABLE TO IDENTIFY PROPERTIES THAT WE WANT TO ACQUIRE OR TO NEGOTIATE ACCEPTABLE PURCHASE PRICES, ACQUISITION FINANCING OR LEASE TERMS FOR NEW PROPERTIES,



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CONTINGENCIES IN OUR SALE AGREEMENTS MAY NOT BE SATISFIED AND OUR PENDING PROPERTY SALES MAY NOT OCCUR, MAY BE DELAYED, OR THE TERMS OF SUCH TRANSACTIONS MAY CHANGE,

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WE MAY BE UNABLE TO REPAY OUR DEBT OBLIGATIONS WHEN THEY BECOME DUE,



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RENTS THAT WE CAN CHARGE AT OUR PROPERTIES MAY DECLINE BECAUSE OF MARKET CONDITIONS OR OTHERWISE,



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WE MAY NOT SUCCEED IN SELLING THE PROPERTIES WE HAVE IDENTIFIED FOR SALE FOR PRICES AT LEAST EQUAL TO THEIR NET BOOK VALUE, ON TERMS WE ARE WILLING TO ACCEPT OR OTHERWISE, DURING 2014 OR AT ALL. ALSO, REMOVAL OF ALL OUR TRUSTEES PURSUANT TO THE RELATED/CORVEX CONSENT SOLICITATION MAY RESULT IN OUR NOT SELLING SOME OR ALL OF THESE PROPERTIES. ACCORDINGLY, SOME OR ALL OF THE PROPERTIES WE HAVE IDENTIFIED FOR SALE MAY NOT BE SOLD OR THE SALES OF THESE PROPERTIES MAY BE DELAYED,



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THE DISTRIBUTIONS WE RECEIVE FROM SIR MAY DECLINE OR WE MAY BE UNABLE TO SELL OUR SIR SHARES FOR AN AMOUNT EQUAL TO OUR CARRYING VALUE OF THOSE SHARES AND ANY SUCH SALE MAY BE AT A DISCOUNT TO MARKET PRICE BECAUSE OF THE LARGE SIZE OF OUR SIR HOLDINGS OR OTHERWISE, AND



•

WE BELIEVE THAT OUR HISTORICAL AND CONTINUING RELATIONSHIPS WITH GOV, SIR, RMR, AIC AND THEIR AFFILIATED AND RELATED PERSONS AND ENTITIES HAVE BEEN AND MAY CONTINUE TO BE OF BENEFIT TO US AND TO PROVIDE US WITH COMPETITIVE ADVANTAGES IN OPERATING AND GROWING OUR BUSINESS; HOWEVER, THE ADVANTAGES WE BELIEVE WE MAY REALIZE FROM THESE RELATIONSHIPS MAY NOT MATERIALIZE.

        THESE RESULTS COULD OCCUR DUE TO MANY DIFFERENT CIRCUMSTANCES, SOME OF WHICH ARE BEYOND OUR CONTROL, SUCH AS THE RESULTS OF THE RELATED/CORVEX CONSENT SOLICITATION, THE RESULTS OF OUR PENDING LITIGATION AND ARBITRATION PROCEEDINGS, NATURAL DISASTERS, CHANGES IN OUR TENANTS' FINANCIAL CONDITIONS, THE MARKET DEMAND FOR LEASED SPACE OR CHANGES IN CAPITAL MARKETS OR THE ECONOMY GENERALLY.

        THE INFORMATION CONTAINED ELSEWHERE IN THIS ANNUAL REPORT ON FORM 10-K OR IN OUR FILINGS WITH THE SEC, INCLUDING UNDER THE CAPTION "RISK FACTORS", OR INCORPORATED HEREIN OR THEREIN, IDENTIFIES OTHER IMPORTANT FACTORS THAT COULD CAUSE DIFFERENCES FROM OUR FORWARD LOOKING STATEMENTS. OUR FILINGS WITH THE SEC ARE AVAILABLE ON THE SEC'S WEBSITE AT WWW.SEC.GOV.

        YOU SHOULD NOT PLACE UNDUE RELIANCE UPON OUR FORWARD LOOKING STATEMENTS.

        EXCEPT AS REQUIRED BY LAW, WE DO NOT INTEND TO UPDATE OR CHANGE ANY FORWARD LOOKING STATEMENTS AS A RESULT OF NEW INFORMATION, FUTURE EVENTS OR OTHERWISE.

STATEMENT CONCERNING LIMITED LIABILITY

        THE AMENDED AND RESTATED DECLARATION OF TRUST ESTABLISHING COMMONWEALTH REIT, DATED JULY 1, 1994, AS AMENDED AND SUPPLEMENTED, AS FILED WITH THE STATE DEPARTMENT OF ASSESSMENTS AND TAXATION OF MARYLAND, PROVIDES THAT NO TRUSTEE, OFFICER, SHAREHOLDER, EMPLOYEE OR AGENT OF COMMONWEALTH REIT SHALL BE HELD TO ANY PERSONAL LIABILITY, JOINTLY OR SEVERALLY, FOR ANY OBLIGATION OF, OR CLAIM AGAINST, COMMONWEALTH REIT. ALL PERSONS DEALING WITH COMMONWEALTH REIT IN ANY WAY SHALL LOOK ONLY TO THE ASSETS OF COMMONWEALTH REIT FOR THE PAYMENT OF ANY SUM OR THE PERFORMANCE OF ANY OBLIGATION.

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COMMONWEALTH REIT
2013 FORM 10-K ANNUAL REPORT

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        References in this Annual Report on Form 10-K to the Company, CWH, we, us or our, refer to CommonWealth REIT and its consolidated subsidiaries as of December 31, 2013, unless the context indicates otherwise. On July 2, 2013, Select Income REIT, or SIR, completed an underwritten public offering of its common shares, at which time we ceased to own a majority of SIR's common shares. Accordingly, following July 2, 2013, we no longer consolidate our investment in SIR, but instead we account for this investment under the equity method.

        The financial information presented in this Annual Report on Form 10-K includes SIR's financial position and results of operations on a consolidated basis with CWH for periods prior to July 2, 2013 when SIR was CWH's consolidated subsidiary, unless the context indicates otherwise. SIR is itself a public company that has common shares registered under the Securities Exchange Act of 1934, as amended. For further information about SIR, please see SIR's periodic reports and other filings with the Securities and Exchange Commission, or the SEC, which are available at the SEC's website at www.sec.gov. References in this Annual Report on Form 10-K to SIR's filings with the SEC are included as textual references only, and the information in SIR's filings with the SEC is not incorporated by reference into this Annual Report on Form 10-K unless otherwise expressly stated herein.

PART I

Item 1.    Business.

        The Company.    We are a real estate investment trust, or REIT, formed in 1986 under the laws of the State of Maryland. Our primary business is the ownership and operation of real estate, primarily office buildings located throughout the United States. For a discussion and information regarding our operating segments, see "Management's Discussion and Analysis of Financial Condition and Results of Operations" in Part II, Item 7 and our financial statements beginning on page F-1 in Part IV, Item 15 of this Annual Report on Form 10-K.

        At December 31, 2013, our portfolio included 125 properties (195 buildings) with a combined 37.3 million square feet (excluding properties classified as held for sale) for a total investment of $5.5 billion at cost and a depreciated book value of $4.6 billion. Our portfolio consisted of: (i) 38 properties (51 buildings) with a combined 21.0 million square feet located in central business district, or CBD, locations, and (ii) 87 properties (144 buildings) with a combined 16.3 million square feet located in suburban locations. Eleven of our properties (11 buildings) with a combined 1.8 million square feet are located in Australia.

        As of December 31, 2013, we also owned 22,000,000 common shares, or approximately 44.2% of the outstanding common shares, of Select Income REIT. We refer to Select Income REIT and its consolidated subsidiaries as SIR. SIR is a REIT that primarily owns and invests in net leased, single tenant office and industrial properties throughout the United States and leased lands in Hawaii and was a 100% owned subsidiary of ours until March 12, 2012, on which date SIR completed an initial public offering of 9,200,000 of its common shares, or the SIR IPO, and became a publicly owned company listed on the New York Stock Exchange, or the NYSE.

        On July 2, 2013, SIR issued and sold to the public 10,500,000 of its common shares. Prior to the completion of this offering, our 22,000,000 common shares of SIR represented approximately 56.0% of SIR's outstanding common shares, and SIR was one of our consolidated subsidiaries. Following the completion of this offering, our 22,000,000 common shares of SIR represented approximately 44.2% of SIR's outstanding common shares, and SIR ceased to be our consolidated subsidiary. As a result of this offering, our investment in SIR was reduced below 50%; consequently, effective July 2, 2013, we no longer consolidate our investment in SIR but instead account for such investment under the equity method.

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        Until March 15, 2013, we also owned 9,950,000, or approximately 18.2%, of the common shares of Government Properties Income Trust, or GOV. GOV, a REIT that primarily owns properties located throughout the United States that are majority leased to government tenants, was our wholly owned subsidiary until its initial public offering in June 2009, when it became a publicly owned company with shares listed on the NYSE.

        See Notes 6 and 12 to the Notes to Consolidated Financial Statements in Part IV, Item 15 of this Annual Report on Form 10-K for additional information regarding SIR and GOV.

        Our principal executive offices are located at Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458-1634, and our telephone number is (617) 332-3990.

        Our investment, financing and disposition policies are established by our Board of Trustees and may be changed by our Board of Trustees at any time without shareholder approval. Our investment goals are current income for distribution to shareholders and capital growth from appreciation in the value of our properties. Our income is derived primarily from rents.

        Investment Policies.    In evaluating potential investments and asset sales, we consider various factors, including but not limited to the following:

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the historical and projected rents received and likely to be received from the property;



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the historical and expected operating expenses, including real estate taxes, incurred and expected to be incurred at the property;



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the growth, tax and regulatory environments of the market in which the property is located;



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the quality, experience and credit worthiness of the property's tenants;



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occupancy and demand for similar properties in the same or nearby markets;



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the construction quality, physical condition and design of the property, and expected capital expenditures that may be needed to be made to the property;



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the location and type of property; and



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the pricing of comparable properties as evidenced by recent market sales.

        We attempt to acquire properties which will enhance the diversity of our portfolio with respect to tenants and locations. However, we have no policies which specifically limit the percentage of our assets which may be invested in any individual property, in any one type of property, in properties in one geographic area, in properties leased to any one tenant or in properties leased to an affiliated group of tenants. We have, however, entered into separate agreements with two of our former wholly owned subsidiaries, GOV and Senior Housing Properties Trust, or SNH, that place certain restrictions on our ability to invest, in the case of GOV's agreement, in properties majority leased to government tenants or, in the case of SNH's agreement, in medical office, clinic and biomedical, pharmaceutical and laboratory buildings (subject, in the case of mixed use buildings, to our retaining the right to invest in any mixed use building for which the rentable square footage is less than 50% medical office, clinic and biomedical, pharmaceutical and laboratory use). We do not believe that these restrictions limit our ability to achieve a diverse portfolio with respect to property locations or tenants.

        We generally prefer 100% owned investments in fee interests. However, circumstances may arise in which we may invest in leaseholds, joint ventures, mortgages and other real estate interests. We may invest in real estate joint ventures if we conclude that by doing so we may benefit from the participation of co-venturers or that our opportunity to participate in the investment is contingent on the use of a joint venture structure. We may invest in participating, convertible or other types of mortgages if we conclude that by doing so we may benefit from the cash flow or appreciation in the

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value of a property which is not available for purchase. Further, we have in the past provided seller financing for properties we have sold and may do so again in the future.

        In the past, we have considered the possibility of entering into mergers or strategic combinations with other companies. We may undertake such considerations in the future. A principal goal of any such transaction will be to increase our profits and diversify their sources.

        Disposition Policies.    From time to time we consider the sale of properties or investments. Disposition decisions are made based on a number of factors including those set forth above under "Investment Policies" and the following:

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the proposed sale price;



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the strategic fit of the property or investment with the rest of our portfolio and our plans; and



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the existence of alternative sources, uses or needs for capital.

        During 2013, we identified 88 properties (244 buildings) for sale. As of the date of this Annual Report on Form 10-K, we have sold 43 of these properties (134 buildings) and two land parcels for an aggregate sale price of $249.1 million, excluding closing costs and other adjustments. We expect to sell the remaining 45 properties (110 buildings) that we identified for sale later in 2014; however, no assurance can be given that any of these properties will be sold in that time period or at all, or what the ultimate terms of those sales may be.

        Financing Policies.    Our revolving credit facility and term loan agreements and our debt indenture and its supplements contain financial covenants that, among other things, restrict our ability to incur indebtedness and require us to maintain certain financial ratios and a minimum net worth. Our Board of Trustees may determine to replace our current credit facility or to seek additional capital through equity offerings, debt financings, retention of cash flows in excess of distributions to shareholders or a combination of these methods. Some of our properties are encumbered by mortgages. To the extent that our Board of Trustees decides to obtain additional debt financing, we may do so on an unsecured basis or a secured basis, subject to limitations in existing financing or other contractual arrangements; we may seek to obtain other lines of credit or to issue securities senior to our common and/or preferred shares, including preferred shares or debt securities which may be convertible into common shares or be accompanied by warrants to purchase common shares; or we may engage in transactions which involve a sale or other conveyance of properties to affiliated or unaffiliated entities. We may finance acquisitions by an exchange of properties, by borrowing under our credit facility, by assuming outstanding mortgage debt on the acquired properties, by the issuance of additional equity or debt securities or by using retained cash flow from operations which may exceed our earnings. The proceeds from any of our financings may be used to pay distributions, to provide working capital, to refinance existing indebtedness or to finance acquisitions and expansions of existing or new properties.

        The borrowing guidelines established by our Board of Trustees and covenants in various debt agreements prohibit us from maintaining a debt to total asset value, as defined, of greater than 60%. Our declaration of trust also limits our borrowings. We may from time to time re-evaluate and modify our financing policies in light of then current market conditions, relative availability and costs of debt and equity capital, the changing values of properties, growth and acquisition opportunities and other factors, and we may increase or decrease our ratio of debt to total capitalization.

        Manager.    Our day to day operations are conducted by RMR. RMR originates and presents investment and divestment opportunities to our Board of Trustees and provides management and administrative services to us. RMR is a Delaware limited liability company beneficially owned by Barry M. Portnoy and Adam D. Portnoy, our Managing Trustees. Adam D. Portnoy is also our President. RMR has a principal place of business at Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458-1634, and its telephone number is (617) 796-8390. RMR also

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acts as the manager to SIR, GOV, Hospitality Properties Trust, or HPT, and SNH, and provides management and other services to other public and private companies, including Five Star Quality Care, Inc., or Five Star, TravelCenters of America LLC, or TA, and Sonesta International Hotels Corporation, or Sonesta. Barry M. Portnoy is the Chairman of RMR, and its other directors are Adam D. Portnoy, Gerard M. Martin, formerly one of our Managing Trustees, and David J. Hegarty. The executive officers of RMR are: Adam D. Portnoy, President and Chief Executive Officer; David M. Blackman, Executive Vice President; Jennifer B. Clark, Executive Vice President and General Counsel; David J. Hegarty, Executive Vice President and Secretary; Mark L. Kleifges, Executive Vice President; Bruce J. Mackey Jr., Executive Vice President; John G. Murray, Executive Vice President; Thomas M. O'Brien, Executive Vice President; John C. Popeo, Executive Vice President; William J. Sheehan, Executive Vice President; Ethan S. Bornstein, Senior Vice President; Richard A. Doyle, Senior Vice President; Paul V. Hoagland, Senior Vice President; Matthew P. Jordan, Senior Vice President, Treasurer and Chief Financial Officer; David M. Lepore, Senior Vice President; Andrew J. Rebholz, Senior Vice President; and Mark R. Young, Senior Vice President. Adam D. Portnoy, David M. Lepore and John C. Popeo are our executive officers, and certain of our executive officers and other executive officers of RMR also serve as officers of other companies to which RMR provides management services.

        Employees.    We have no employees. Services which would be provided by employees are provided by RMR and by our Managing Trustees and officers. As of February 24, 2014, RMR had approximately 850 full time employees, including a headquarters staff and regional offices and personnel located throughout the United States and one affiliated office in Sydney, Australia.

        Competition.    Investing in and operating office real estate is a highly competitive business. We compete against other REITs, numerous financial institutions, individuals and public and private companies who are actively engaged in this business. Also, we compete for tenants and investments based on a number of factors including pricing, underwriting criteria and reputation. Our ability to successfully compete is also impacted by economic and population trends, availability of acceptable investment opportunities, our ability to negotiate beneficial leasing and investment terms, availability and cost of capital and new and existing laws and regulations. Some of our competitors are dominant in selected geographic markets, including in markets in which we operate. Many of our competitors have greater financial and other resources than we have. We believe the geographic diversity of our investments, the experience and abilities of our management, the quality of our assets and the financial strength of many of our tenants affords us some competitive advantages which have and will allow us to operate our business successfully despite the competitive nature of our business.

        For additional information on competition and the risks associated with our business, please see "Risk Factors" in Part I, Item 1A of this Annual Report on Form 10-K.

        Environmental and Climate Change Matters.    Under various laws, owners as well as tenants and operators of real estate may be required to investigate and clean up or remove hazardous substances present at or migrating from properties they own, lease or operate and may be held liable for property damage or personal injuries that result from such hazardous substances. These laws also expose us to the possibility that we may become liable to reimburse governments or other parties for damages and costs they incur in connection with such hazardous substances. We estimate the cost to remove hazardous substances at some of our properties based in part on environmental surveys conducted prior to our purchase of the properties and we considered those costs when determining an acceptable purchase price. Estimated liabilities related to hazardous substances at properties we own are reflected in our consolidated balance sheets and included in the cost of the real estate acquired.

        Certain of our buildings contain asbestos. We believe any asbestos in our buildings is contained in accordance with current regulations, and we have no current plans to remove any such asbestos. If we

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remove the asbestos or renovate or demolish these properties, certain environmental regulations govern the manner in which the asbestos must be handled and removed.

        We do not believe that there are environmental conditions at any of our properties that have had or will have a material adverse effect on us. However, no assurances can be given that conditions are not present at our properties or that costs we may be required to incur in the future to remediate contamination will not have a material adverse effect on our business or financial condition.

        The current political debate about climate change has resulted in various treaties, laws and regulations which are intended to limit carbon emissions. We believe these laws being enacted or proposed may cause energy costs at our properties to increase, but we do not expect the direct impact of these increases to be material to our results of operations because the increased costs either would be the responsibility of our tenants directly or in large part may be passed through by us to our tenants as additional lease payments. Although we do not believe it is likely in the foreseeable future, laws enacted to mitigate climate change may make some of our buildings obsolete or cause us to make material investments in our properties which could materially and adversely affect our financial condition. For more information regarding climate change matters and their possible adverse impact on us, see "Risk Factors—Risks Related to Our Business—Ownership of real estate is subject to environmental and climate change risks" in Part I, Item 1A and "Management's Discussion and Analysis—Impact of Climate Change" in Part II, Item 7 of this Annual Report on Form 10-K.

        We and our manager, RMR, continuously study ways to improve the energy efficiency at all of our properties. RMR is a member of the Energy Star Partner program, a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy which is focused on promoting energy efficiency and sustainability at commercial properties through its ENERGY STAR label program, and a member of the U.S. Green Building Council, a nonprofit organization focused on promoting energy efficiency and sustainability at commercial properties through its leadership in energy and environmental design, or LEED®, green building program.

        Internet Website.    Our internet website address is www.cwhreit.com. Copies of our governance guidelines, code of business conduct and ethics, or Code of Conduct, policy outlining procedures for handling concerns or complaints about accounting, internal accounting controls or auditing matters, and the charters of our audit, compensation and nominating and governance committees are posted on our website and may be obtained free of charge by writing to our Secretary, CommonWealth REIT, Two Newton Place, 255 Washington Street, Suite 300, Newton, Massachusetts 02458-1634. We make available, free of charge, on our website, our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to these reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, as soon as reasonably practicable after these forms are filed with, or furnished to, the SEC. Any shareholder or other interested party who desires to communicate with our non-management Trustees, individually or as a group, may do so by filling out a report on our website. Our Board of Trustees also provides a process for security holders to send communications to the entire Board of Trustees. Information about the process for sending communications to our Board of Trustees can be found on our website. Our website address is included several times in this Annual Report on Form 10-K as a textual reference only and the information on the website is not incorporated by reference into this Annual Report on Form 10-K.

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FEDERAL INCOME TAX CONSIDERATIONS

        The following summary of United States federal income tax considerations is based on existing law, and is limited to investors who own our shares as investment assets rather than as inventory or as property used in a trade or business. The summary does not discuss all of the particular tax consequences that might be relevant to you if you are subject to special rules under federal income tax law, for example if you are:

•

a bank, insurance company or other financial institution;



•

a regulated investment company or REIT;



•

a subchapter S corporation;



•

a broker, dealer or trader in securities or foreign currency;



•

a person who marks-to-market our shares;



•

a person who has a functional currency other than the United States dollar;



•

a person who acquires our shares in connection with employment or other performance of services;



•

a person subject to alternative minimum tax;



•

a person who owns our shares as part of a straddle, hedging transaction, constructive sale transaction, constructive ownership transaction or conversion transaction;



•

a United States expatriate; or



•

except as specifically described in the following summary, a trust, estate, tax-exempt entity or foreign person.

        The sections of the United States Internal Revenue Code of 1986, as amended, or the IRC, that govern the federal income tax qualification and treatment of a REIT and its shareholders are complex. This presentation is a summary of applicable IRC provisions, related rules and regulations and administrative and judicial interpretations, all of which are subject to change, possibly with retroactive effect. Future legislative, judicial or administrative actions or decisions could also affect the accuracy of statements made in this summary. We have not received a ruling from the United States Internal Revenue Service, or the IRS, with respect to any matter described in this summary, and we cannot assure you that the IRS or a court will agree with all of the statements made in this summary. The IRS or a court could, for example, take a different position from that described in this summary with respect to our acquisitions, operations, restructurings or other matters, which, if successful, could result in significant tax liabilities for applicable parties. In addition, this summary is not exhaustive of all possible tax consequences, and does not discuss any estate, gift, state, local or foreign tax consequences. For all these reasons, we urge you and any prospective acquiror of our shares to consult with a tax advisor about the federal income tax and other tax consequences of the acquisition, ownership and disposition of our shares. Our intentions and beliefs described in this summary are based upon our understanding of applicable laws and regulations that are in effect as of the date of this Annual Report on Form 10-K. If new laws or regulations are enacted which impact us directly or indirectly, we may change our intentions or beliefs.

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        Your federal income tax consequences may differ depending on whether or not you are a "U.S. shareholder." For purposes of this summary, a "U.S. shareholder" is a beneficial owner of our shares who is:

•

a citizen or resident of the United States, including an alien individual who is a lawful permanent resident of the United States or meets the substantial presence residency test under the federal income tax laws;



•

an entity treated as a corporation for federal income tax purposes that is created or organized in or under the laws of the United States, any state thereof or the District of Columbia;



•

an estate the income of which is subject to federal income taxation regardless of its source; or



•

a trust if a court within the United States is able to exercise primary supervision over the administration of the trust and one or more United States persons have the authority to control all substantial decisions of the trust, or, to the extent provided in Treasury regulations, a trust in existence on August 20, 1996 that has elected to be treated as a domestic trust;

whose status as a U.S. shareholder is not overridden by an applicable tax treaty. Conversely, a "non-U.S. shareholder" is a beneficial owner of our shares who is not a U.S. shareholder.

        If a partnership (including any entity treated as a partnership for federal income tax purposes) is a beneficial owner of our shares, the tax treatment of a partner in the partnership generally will depend upon the status of the partner and the activities of the partnership. A beneficial owner that is a partnership and partners in such a partnership are urged to consult their tax advisors about the federal income tax consequences of the acquisition, ownership and disposition of our shares.

Taxation as a REIT

        We have elected to be taxed as a REIT under Sections 856 through 860 of the IRC, commencing with our taxable year ended December 31, 1987. Our REIT election, assuming continuing compliance with the then applicable qualification tests, will continue in effect for subsequent taxable years. Although no assurance can be given, we believe that we have been organized and have operated, and will continue to be organized and to operate, in a manner that qualified and will continue to qualify us to be taxed under the IRC as a REIT.

        As a REIT, we generally are not subject to federal income tax on our net income distributed as dividends to our shareholders. Distributions to our shareholders generally are included in their income as dividends to the extent of our current or accumulated earnings and profits. Our dividends are not generally entitled to the preferential tax rates on qualified dividend income, but a portion of our dividends may be treated as capital gain dividends or as qualified dividend income, all as explained below. No portion of any of our dividends is eligible for the dividends received deduction for corporate shareholders. Distributions in excess of current or accumulated earnings and profits generally are treated for federal income tax purposes as returns of capital to the extent of a recipient shareholder's basis in our shares, and will reduce this basis. Our current or accumulated earnings and profits are generally allocated first to distributions made on our preferred shares, and thereafter to distributions made on our common shares. For all these purposes, our distributions include both cash distributions and any in kind distributions of property that we might make.

        The conversion formula of our series D cumulative convertible preferred shares and our series E cumulative redeemable preferred shares may be adjusted under a number of circumstances; adjustments may include changes in the type or amount of consideration a shareholder receives upon conversion. Section 305 of the IRC treats some of these adjustments as constructive distributions, in which case they would be taxable in a similar manner to actual distributions. In general, a shareholder that holds our series D cumulative convertible preferred shares or our series E cumulative redeemable

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preferred shares would be deemed to receive a constructive distribution if the conversion price is adjusted for a taxable distribution to the holders of common shares. Such a shareholder's adjusted tax basis in, as applicable, series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares would be increased by constructive distributions that are taxable as dividends or gain, and would be unaffected by constructive distributions that are nontaxable returns of capital. Conversely, a failure to appropriately adjust the conversion price of, as applicable, our series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares could result in a constructive distribution to shareholders that hold our common shares, which would be taxable to them in a similar manner as actual distributions. A shareholder may also receive a constructive distribution if a conversion of its series D cumulative convertible preferred shares or its series E cumulative redeemable preferred shares is accompanied by a change in the conversion formula.

        If a shareholder actually or constructively owns none or a small percentage of our common shares, and such shareholder surrenders its preferred shares to us to be repurchased for cash only, then the repurchase of the preferred shares is likely to qualify for sale or exchange treatment because the repurchase would not be "essentially equivalent to a dividend" as defined by the IRC. More specifically, a cash repurchase of preferred shares will be treated under Section 302 of the IRC as a distribution, and hence taxable as a dividend to the extent of our allocable current or accumulated earnings and profits, as discussed above, unless the repurchase satisfies one of the tests set forth in Section 302(b) of the IRC and is therefore treated as a sale or exchange of the repurchased shares. The repurchase will be treated as a sale or exchange if it (1) is "substantially disproportionate" with respect to the surrendering shareholder's ownership in us, (2) results in a "complete termination" of the surrendering shareholder's common and preferred share interest in us, or (3) is "not essentially equivalent to a dividend" with respect to the surrendering shareholder, all within the meaning of Section 302(b) of the IRC. In determining whether any of these tests have been met, a shareholder must generally take into account our common and preferred shares considered to be owned by such shareholder by reason of constructive ownership rules set forth in the IRC, as well as our common and preferred shares actually owned by such shareholder. In addition, if a repurchase is treated as a distribution under the preceding tests, then a shareholder's tax basis in the repurchased preferred shares generally will be transferred to the shareholder's remaining shares of our common or preferred shares, if any, and if such shareholder owns no other shares of our common or preferred shares, such basis generally may be transferred to a related person or may be lost entirely. Because the determination as to whether a shareholder will satisfy any of the tests of Section 302(b) of the IRC depends upon the facts and circumstances at the time that the preferred shares are repurchased, we encourage you to consult your own tax advisor to determine your particular tax treatment.

        Our counsel, Sullivan & Worcester LLP, has provided to us an opinion that we have been organized and have qualified as a REIT under the IRC for our 1987 through 2013 taxable years, and that our current investments and current and anticipated plan of operation will enable us to continue to meet the requirements for qualification and taxation as a REIT under the IRC. Our counsel's opinions are conditioned upon the assumption that our leases, our declaration of trust and all other legal documents to which we are or have been a party have been and will be complied with by all parties to those documents, upon the accuracy and completeness of the factual matters described in this Annual Report on Form 10-K and upon representations made by us as to certain factual matters relating to our organization and operations and our expected manner of operation. If this assumption or a representation is inaccurate or incomplete, our counsel's opinions may be adversely affected and may not be relied upon. The opinions of our counsel are based upon the law as it exists today, but the law may change in the future, possibly with retroactive effect. Given the highly complex nature of the rules governing REITs, the ongoing importance of factual determinations, and the possibility of future changes in our circumstances, no assurance can be given by Sullivan & Worcester LLP or us that we will qualify as or be taxed as a REIT for any particular year. Any opinion of Sullivan & Worcester LLP as to our qualification or taxation as a REIT will be expressed as of the date issued. Our counsel will

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have no obligation to advise us or our shareholders of any subsequent change in the matters stated, represented or assumed or of any subsequent change in the applicable law. Also, the opinions of our counsel are not binding on either the IRS or a court, and either could take a position different from that expressed by our counsel.

        Our continued qualification and taxation as a REIT will depend upon our compliance on a continuing basis with various qualification tests imposed under the IRC and summarized below. While we believe that we will satisfy these tests, our counsel does not review compliance with these tests on a continuing basis. If we fail to qualify as a REIT in any year, we will be subject to federal income taxation as if we were a corporation taxed under subchapter C of the IRC, or a C corporation, and our shareholders will be taxed like shareholders of C corporations, meaning that federal income tax generally will be applied at both the corporate and shareholder levels. In this event, we could be subject to significant tax liabilities, and the amount of cash available for distribution to our shareholders could be reduced or eliminated.

        If we qualify as a REIT and meet the tests described below, we generally will not pay federal income tax on amounts we distribute to our shareholders. However, even if we qualify as a REIT, we may be subject to federal tax in the following circumstances:

•

We will be taxed at regular corporate rates on any undistributed "real estate investment trust taxable income," including our undistributed net capital gains.



•

If our alternative minimum taxable income exceeds our taxable income, we may be subject to the corporate alternative minimum tax on our items of tax preference.



•

If we have net income from the disposition of "foreclosure property" that is held primarily for sale to customers in the ordinary course of business or from other nonqualifying income from foreclosure property, we will be subject to tax on this income at the highest regular corporate rate, currently 35%.



•

If we have net income from prohibited transactions—that is, dispositions of inventory or property held primarily for sale to customers in the ordinary course of business other than dispositions of foreclosure property and other than dispositions excepted under a statutory safe harbor—we will be subject to tax on this income at a 100% rate.



•

If we fail to satisfy the 75% gross income test or the 95% gross income test discussed below, but nonetheless maintain our qualification as a REIT, we will be subject to tax at a 100% rate on the greater of the amount by which we fail the 75% or the 95% test, with adjustments, multiplied by a fraction intended to reflect our profitability.



•

If we fail to distribute for any calendar year at least the sum of 85% of our REIT ordinary income for that year, 95% of our REIT capital gain net income for that year and any undistributed taxable income from prior periods, we will be subject to a 4% nondeductible excise tax on the excess of the required distribution over the amounts actually distributed.



•

If we acquire an asset from a corporation in a transaction in which our basis in the asset is determined by reference to the basis of the asset in the hands of a present or former C corporation, and if we subsequently recognize gain on the disposition of this asset during a specified period (generally ten years) beginning on the date on which the asset ceased to be owned by the C corporation, then we will pay tax at the highest regular corporate tax rate, which is currently 35%, on the lesser of the excess of the fair market value of the asset over the C corporation's basis in the asset on the date the asset ceased to be owned by the C corporation, or the gain we recognize in the disposition. We currently do not expect to sell any asset if such a sale would result in the imposition of a material tax liability. We cannot, however, provide assurance that we will not change our plan in this regard.

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•

If we acquire a corporation in a transaction where we succeed to its tax attributes, to preserve our status as a REIT we must generally distribute all of the C corporation earnings and profits inherited in that acquisition, if any, not later than the end of our taxable year in which the acquisition occurs. However, if we fail to do so, relief provisions would allow us to maintain our status as a REIT provided we distribute any subsequently discovered C corporation earnings and profits and pay an interest charge in respect of the period of delayed distribution. As discussed below, we have acquired C corporations in connection with our acquisition of real estate. In each such acquisition, we have either made an election under Section 338 of the IRC to purge the earnings and profits of the acquired C corporation, or investigated the acquired C corporation and found that it did not have undistributed earnings and profits that we inherited but failed to timely distribute. However, upon review or audit, the IRS may disagree.



•

As summarized below, REITs are permitted within limits to own stock and securities of a "taxable REIT subsidiary." A taxable REIT subsidiary is separately taxed on its net income as a C corporation, and is subject to limitations on the deductibility of interest expense paid to its REIT parent. In addition, its REIT parent is subject to a 100% tax on the difference between amounts charged and redetermined rents and deductions, including excess interest.



•

In 2010, we acquired office and industrial properties in Australia. Our profits from properties outside of the United States will generally be subject to tax in the local jurisdictions. Under currently applicable law and through available tax concessions, for which we have received a favorable Australian private letter ruling, we have minimized the Australian income taxes we must pay, but there can be no assurance that existing law or concessions will be available to us in the future to minimize taxes. If we continue to operate as we do, then we will distribute all of our taxable income to our shareholders such that we will generally not pay federal income tax. As a result, we cannot recover the cost of foreign income taxes imposed on our foreign investments by claiming foreign tax credits against our federal income tax liability. Also, as a REIT, we cannot pass through to our shareholders any foreign tax credits.

        If we fail to qualify as a REIT or elect not to qualify as a REIT, then we will be subject to federal income tax in the same manner as a regular C corporation. Further, as a regular C corporation, distributions to our shareholders will not be deductible by us, nor will distributions be required under the IRC. Also, to the extent of our current and accumulated earnings and profits, all distributions to our shareholders will generally be taxable as ordinary dividends potentially eligible for the preferential tax rates discussed below in "Taxation of U.S. Shareholders" and, subject to limitations in the IRC, will be potentially eligible for the dividends received deduction for corporate shareholders. Finally, we will generally be disqualified from qualification as a REIT for the four taxable years following the taxable year in which the termination is effective. Our failure to qualify as a REIT for even one year could result in reduction or elimination of distributions to our shareholders, or in our incurring substantial indebtedness or liquidating substantial investments in order to pay the resulting corporate-level taxes. The IRC provides relief provisions under which we might avoid automatically ceasing to be a REIT for failure to meet specified REIT requirements, all as discussed in more detail below.

REIT Qualification Requirements

        General Requirements.    Section 856(a) of the IRC defines a REIT as a corporation, trust or association:

(1)

that is managed by one or more trustees or directors;



(2)

the beneficial ownership of which is evidenced by transferable shares or by transferable certificates of beneficial interest;



(3)

that would be taxable, but for Sections 856 through 859 of the IRC, as a C corporation;

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(4)

that is not a financial institution or an insurance company subject to special provisions of the IRC;



(5)

the beneficial ownership of which is held by 100 or more persons;



(6)

that is not "closely held" as defined under the personal holding company stock ownership test, as described below; and



(7)

that meets other tests regarding income, assets and distributions, all as described below.

Section 856(b) of the IRC provides that conditions (1) through (4) must be met during the entire taxable year and that condition (5) must be met during at least 335 days of a taxable year of 12 months, or during a proportionate part of a taxable year of less than 12 months. Section 856(h)(2) of the IRC provides that neither condition (5) nor (6) need to have been met during our first taxable year as a REIT. We believe that we have met conditions (1) through (7) during each of the requisite periods ending on or before the close of our most recently completed taxable year, and that we will continue to meet these conditions in future taxable years. There can, however, be no assurance in this regard.

        By reason of condition (6), we will fail to qualify as a REIT for a taxable year if at any time during the last half of a year (except for our first taxable year as a REIT) more than 50% in value of our outstanding shares is owned directly or indirectly by five or fewer individuals. To help comply with condition (6), our declaration of trust and bylaws restrict transfers of our shares that would otherwise result in concentrated ownership positions. In addition, if we comply with applicable Treasury regulations to ascertain the ownership of our outstanding shares and do not know, or by exercising reasonable diligence would not have known, that we failed condition (6), then we will be treated as having met condition (6). However, our failure to comply with these regulations for ascertaining ownership may result in a penalty of $25,000, or $50,000 for intentional violations. Accordingly, we have complied and will continue to comply with these regulations, including requesting annually from record holders of significant percentages of our shares information regarding the ownership of our shares. Under our declaration of trust and bylaws, our shareholders are required to respond to these requests for information. A shareholder who fails or refuses to comply with the request is required by Treasury regulations to submit a statement with its federal income tax return disclosing its actual ownership of our shares and other information.

        For purposes of condition (6), the term "individuals" is defined in the IRC to include natural persons, supplemental unemployment compensation benefit plans, private foundations and portions of a trust permanently set aside or used exclusively for charitable purposes, but not other entities or qualified pension plans or profit-sharing trusts. As a result, REIT shares owned by an entity that is not an "individual" are considered to be owned by the direct and indirect owners of the entity that are individuals (as so defined), rather than to be owned by the entity itself. Similarly, REIT shares held by a qualified pension plan or profit-sharing trust are treated as held directly by the individual beneficiaries in proportion to their actuarial interests in such plan or trust. Consequently, five or fewer such trusts could own more than 50% of the interests in an entity without jeopardizing that entity's federal income tax qualification as a REIT. However, as discussed below, if a REIT is a "pension-held REIT," each qualified pension plan or profit-sharing pension trust owning more than 10% of the REIT's shares by value generally may be taxed on a portion of the dividends it receives from the REIT.

        The IRC provides that we will not automatically fail to be a REIT if we do not meet conditions (1) through (6), provided we can establish that such failure was due to reasonable cause and not due to willful neglect. Each such excused failure will result in the imposition of a $50,000 penalty instead of REIT disqualification. It is impossible to state whether in all circumstances we would be entitled to the benefit of this relief provision. This relief provision applies to any failure of the applicable conditions, even if the failure first occurred in a prior taxable year.

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        Our Wholly Owned Subsidiaries and Our Investments Through Partnerships.    Except in respect of taxable REIT subsidiaries as discussed below, Section 856(i) of the IRC provides that any corporation, 100% of whose stock is held by a REIT and its disregarded subsidiaries, is a qualified REIT subsidiary and shall not be treated as a separate corporation. The assets, liabilities and items of income, deduction and credit of a qualified REIT subsidiary are treated as the REIT's. We believe that each of our direct and indirect wholly owned subsidiaries, other than the taxable REIT subsidiaries discussed below, will be either a qualified REIT subsidiary within the meaning of Section 856(i) of the IRC, or a noncorporate entity that for federal income tax purposes is not treated as separate from its owner under Treasury regulations issued under Section 7701 of the IRC. Thus, except for the taxable REIT subsidiaries discussed below, in applying all the federal income tax REIT qualification requirements described in this summary, all assets, liabilities and items of income, deduction and credit of our direct and indirect wholly owned subsidiaries are treated as ours.

        We have invested and may invest in real estate through one or more entities that are treated as partnerships for federal income tax purposes, including limited or general partnerships, limited liability companies or foreign entities. In the case of a REIT that is a partner in a partnership, Treasury regulations provide that, for purposes of the REIT qualification requirements regarding income and assets discussed below, the REIT is deemed to own its proportionate share of the assets of the partnership corresponding to the REIT's proportionate capital interest in the partnership and is deemed to be entitled to the income of the partnership attributable to this proportionate share. In addition, for these purposes, the character of the assets and items of gross income of the partnership generally remains the same in the hands of the REIT. Accordingly, our proportionate share of the assets, liabilities, and items of income of each partnership in which we are or become a partner is treated as ours for purposes of the income tests and asset tests discussed below. In contrast, for purposes of the distribution requirement discussed below, we must take into account as a partner our share of the partnership's income as determined under the general federal income tax rules governing partners and partnerships under Sections 701 through 777 of the IRC.

        Taxable REIT Subsidiaries.    We are permitted to own any or all of the securities of a "taxable REIT subsidiary" as defined in Section 856(l) of the IRC, provided that no more than 25% of the total value of our assets, at the close of each quarter, is comprised of our investments in the stock or securities of our taxable REIT subsidiaries. Among other requirements, a taxable REIT subsidiary of ours must:

(1)

be a corporation (other than a REIT) for federal income tax purposes in which we directly or indirectly own shares;



(2)

join with us in making a taxable REIT subsidiary election;



(3)

not directly or indirectly operate or manage a lodging facility or a health care facility; and



(4)

not directly or indirectly provide to any person, under a franchise, license or otherwise, rights to any brand name under which any lodging facility or health care facility is operated, except that in limited circumstances a subfranchise, sublicense or similar right can be granted to an independent contractor to operate or manage a lodging facility or a health care facility.

        In addition, any corporation (other than a REIT) in which a taxable REIT subsidiary directly or indirectly owns more than 35% of the voting power or value of the outstanding securities of such corporation will automatically be treated as a taxable REIT subsidiary. Subject to the discussion below, we believe that we and each of our taxable REIT subsidiaries have complied with, and will continue to comply with, on a continuous basis, the requirements for taxable REIT subsidiary status at all times during which the subsidiary's taxable REIT subsidiary election is reported as being in effect, and we believe that the same will be true for any taxable REIT subsidiary that we later form or acquire.

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        Our ownership of stock and securities in taxable REIT subsidiaries is exempt from the 10% and 5% REIT asset tests discussed below. Also, as discussed below, taxable REIT subsidiaries can perform services for our tenants without disqualifying the rents we receive from those tenants under the 75% or 95% gross income tests discussed below. Moreover, because taxable REIT subsidiaries are taxed as C corporations that are separate from us, their assets, liabilities and items of income, deduction and credit generally are not imputed to us for purposes of the REIT qualification requirements described in this summary. Therefore, taxable REIT subsidiaries can generally undertake third-party management and development activities and activities not related to real estate.

        Restrictions are imposed on taxable REIT subsidiaries to ensure that they will be subject to an appropriate level of federal income taxation. For example, a taxable REIT subsidiary may not deduct interest paid in any year to an affiliated REIT to the extent that the interest payments exceed, generally, 50% of the taxable REIT subsidiary's adjusted taxable income for that year. However, the taxable REIT subsidiary may carry forward the disallowed interest expense to a succeeding year, and deduct the interest in that later year subject to that year's 50% adjusted taxable income limitation. In addition, if a taxable REIT subsidiary pays interest, rent or other amounts to its affiliated REIT in an amount that exceeds what an unrelated third party would have paid in an arm's length transaction, then the REIT generally will be subject to an excise tax equal to 100% of the excessive portion of the payment. Finally, if in comparison to an arm's length transaction, a tenant has overpaid rent to the REIT in exchange for underpaying the taxable REIT subsidiary for services rendered, and if the REIT has not adequately compensated the taxable REIT subsidiary for services provided to or on behalf of a tenant, then the REIT may be subject to an excise tax equal to 100% of the undercompensation to the taxable REIT subsidiary. There can be no assurance that arrangements involving our taxable REIT subsidiaries will not result in the imposition of one or more of these deduction limitations or excise taxes, but we do not believe that we or our taxable REIT subsidiaries are or will be subject to these impositions.

        Income Tests.    There are two gross income requirements for qualification as a REIT under the IRC:

•

At least 75% of our gross income (excluding: (a) gross income from sales or other dispositions of property held primarily for sale; (b) any income arising from "clearly identified" hedging transactions that we enter into to manage interest rate or price changes or currency fluctuations with respect to borrowings we incur to acquire or carry real estate assets; (c) any income arising from "clearly identified" hedging transactions that we enter into primarily to manage risk of currency fluctuations relating to any item that qualifies under the 75% or 95% gross income tests (or any property that generates such income or gain); (d) real estate foreign exchange gain (as defined in Section 856(n)(2) of the IRC); and (e) income from the repurchase or discharge of indebtedness) must be derived from investments relating to real property, including "rents from real property" as defined under Section 856 of the IRC, interest and gain from mortgages on real property or on interests in real property, income and gain from foreclosure property, gain from the sale or other disposition of real property other than dealer property, or dividends and gain from shares in other REITs. When we receive new capital in exchange for our shares or in a public offering of five-year or longer debt instruments, income attributable to the temporary investment of this new capital in stock or a debt instrument, if received or accrued within one year of our receipt of the new capital, is generally also qualifying income under the 75% gross income test.



•

At least 95% of our gross income (excluding: (a) gross income from sales or other dispositions of property held primarily for sale; (b) any income arising from "clearly identified" hedging transactions that we enter into to manage interest rate or price changes or currency fluctuations with respect to borrowings we incur to acquire or carry real estate assets; (c) any income arising from "clearly identified" hedging transactions that we enter into primarily to manage risk of

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currency fluctuations relating to any item that qualifies under the 75% or 95% gross income tests (or any property that generates such income or gain); (d) passive foreign exchange gain (as defined in Section 856(n)(3) of the IRC); and (e) income from the repurchase or discharge of indebtedness) must be derived from a combination of items of real property income that satisfy the 75% gross income test described above, dividends, interest, or gains from the sale or disposition of stock, securities or real property.

For purposes of the 75% and 95% gross income tests outlined above, income derived from a "shared appreciation provision" in a mortgage loan is generally treated as gain recognized on the sale of the property to which it relates. Although we will use our best efforts to ensure that the income generated by our investments will be of a type that satisfies both the 75% and 95% gross income tests, there can be no assurance in this regard.

        In order to qualify as "rents from real property" under Section 856 of the IRC, several requirements must be met:

•

The amount of rent received generally must not be based on the income or profits of any person, but may be based on receipts or sales.



•

Rents do not qualify if the REIT owns 10% or more by vote or value of the tenant, whether directly or after application of attribution rules. While we intend not to lease property to any party if rents from that property would not qualify as rents from real property, application of the 10% ownership rule is dependent upon complex attribution rules and circumstances that may be beyond our control. For example, an unaffiliated third party's ownership directly or by attribution of 10% or more by value of our shares, as well as an ownership position in the stock of one of our tenants which, when added to our own ownership position in that tenant, totals 10% or more by vote or value of the stock of that tenant, would result in that tenant's rents not qualifying as rents from real property. Our declaration of trust and bylaws disallow transfers or purported acquisitions, directly or by attribution, of our shares to the extent necessary to maintain our REIT status under the IRC. Similarly, for the purpose of SIR retaining its own REIT status under the IRC, SIR's organizational documents contain similar provisions to limit concentrated ownership of beneficial positions in SIR. Furthermore, for as long as we own more than 9.8% of SIR's outstanding shares, the transaction agreement we made with SIR provides that we and SIR will limit ownership in any of our tenants to no more than 4.9% by each party, so that our combined ownership will remain under 10%, and we and SIR have also agreed to take reasonable actions to facilitate the REIT status under the IRC of the other. Nevertheless, there can be no assurance that these provisions in our declaration of trust and bylaws and in our transaction agreement with SIR will be effective to prevent our REIT status from being jeopardized under the 10% affiliated tenant rule. Furthermore, there can be no assurance that we will be able to monitor and enforce these restrictions, nor will our shareholders necessarily be aware of ownership of shares attributed to them under the IRC's attribution rules.



•

There is a limited exception to the above prohibition on earning "rents from real property" from a 10% affiliated tenant where the tenant is a taxable REIT subsidiary. If at least 90% of the leased space of a property is leased to tenants other than taxable REIT subsidiaries and 10% affiliated tenants, and if the taxable REIT subsidiary's rent for space at that property is substantially comparable to the rents paid by nonaffiliated tenants for comparable space at the property, then otherwise qualifying rents paid by the taxable REIT subsidiary to the REIT will not be disqualified on account of the rule prohibiting 10% affiliated tenants.



•

In order for rents to qualify, we generally must not manage the property or furnish or render services to the tenants of the property, except through an independent contractor from whom we derive no income or through one of our taxable REIT subsidiaries. There is an exception to this rule permitting a REIT to perform customary tenant services of the sort that a tax-exempt

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organization could perform without being considered in receipt of "unrelated business taxable income" as defined in Section 512(b)(3) of the IRC. In addition, a de minimis amount of noncustomary services will not disqualify income as "rents from real property" so long as the value of the impermissible services does not exceed 1% of the gross income from the property.

•

If rent attributable to personal property leased in connection with a lease of real property is 15% or less of the total rent received under the lease, then the rent attributable to personal property will qualify as "rents from real property" if this 15% threshold is exceeded, the rent attributable to personal property will not so qualify. The portion of rental income treated as attributable to personal property is determined according to the ratio of the fair market value of the personal property to the total fair market value of the real and personal property that is rented.

We believe that all or substantially all of our rents have qualified and will qualify as rents from real property for purposes of Section 856 of the IRC.

        In order to qualify as mortgage interest on real property for purposes of the 75% test, interest must derive from a mortgage loan secured by real property with a fair market value at the time the loan is made (reduced by any senior liens on the property) at least equal to the amount of the loan. If the amount of the loan exceeds the fair market value of the real property (as so reduced by senior liens), the interest will be treated as interest on a mortgage loan in a ratio equal to the ratio of the fair market value of the real property (as so reduced by senior liens) to the total amount of the mortgage loan.

        We have maintained, and will continue to maintain, appropriate books and records for our Australian properties in Australian dollars. Accordingly, for federal income tax purposes, including presumably the 75% and 95% gross income tests summarized above, our income, gains and losses from our Australian operations will generally be calculated first in Australian dollars, and then translated into United States dollars at appropriate exchange rates. On the periodic repatriation of monies from our Australian operations to the United States, we will be required to recognize foreign exchange gains or losses; however, any foreign exchange gains we recognize from repatriation are expected to constitute "real estate foreign exchange gains" under Section 856(n)(2) of the IRC, and thus be excluded from the 75% and 95% gross income tests summarized above.

        Absent the "foreclosure property" rules of Section 856(e) of the IRC, a REIT's receipt of business operating income from a property would not qualify under the 75% and 95% gross income tests. But as foreclosure property, gross income from such a business operation would so qualify. In the case of property leased by a REIT to a tenant, foreclosure property is defined under applicable Treasury regulations to include generally the real property and incidental personal property that the REIT reduces to possession upon a default or imminent default under the lease by the tenant, and as to which a foreclosure property election is made by attaching an appropriate statement to the REIT's federal income tax return. Any gain that a REIT recognizes on the sale of foreclosure property held as inventory or primarily for sale to customers, plus any income it receives from foreclosure property that would not qualify under the 75% gross income test in the absence of foreclosure property treatment, reduced by expenses directly connected with the production of those items of income, would be subject to income tax at the maximum corporate rate, currently 35%, under the foreclosure property income tax rules of Section 857(b)(4) of the IRC. Thus, if a REIT should lease foreclosure property in exchange for rent that qualifies as "rents from real property" as described above, then that rental income is not subject to the foreclosure property income tax.

        Other than sales of foreclosure property, any gain we realize on the sale of property held as inventory or other property held primarily for sale to customers in the ordinary course of business will be treated as income from a prohibited transaction that is subject to a penalty tax at a 100% rate. This prohibited transaction income also may adversely affect our ability to satisfy the 75% and 95% gross

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income tests for federal income tax qualification as a REIT. Whether property is held as inventory or primarily for sale to customers in the ordinary course of a trade or business is a question of fact that depends on all the facts and circumstances surrounding the particular transaction. We therefore cannot provide assurances as to whether or not the IRS might successfully assert that one or more of our dispositions is subject to the 100% penalty tax. Sections 857(b)(6)(C) and (E) of the IRC provide a safe harbor pursuant to which limited sales of real property held at least two years and meeting specified additional requirements will not be treated as prohibited transactions. However, compliance with the safe harbor is not always achievable in practice.

        Our Board of Trustees has approved a plan to reposition our portfolio toward high quality office buildings located in CBDs and away from suburban office and industrial properties. This repositioning process began in 2013 and sales are expected to continue into 2014. We believe that dispositions related to the repositioning of our portfolio along with other dispositions that we have made or that we might make in the future will not be subject to the 100% penalty tax, because our general intent has been and is to:

•

own our assets for investment with a view to long-term income production and capital appreciation;



•

engage in the business of developing, owning, leasing and managing our existing properties and acquiring, developing, owning, leasing and managing new properties; and



•

make occasional dispositions of our assets consistent with our long-term investment objectives.

        In addition, we believe that the prohibited transactions safe harbor under Section 857(b)(6)(C) and (E) of the IRC applied to each of our 2013 real estate sales in which we recognized a gain and thus no prohibited transactions tax would be owing for that reason too; however, because application of the prohibited transactions safe harbor is complex, there can be no assurance that our prior real estate sales have, or any future real estate sales will, come within the safe harbor.

        If we fail to satisfy one or both of the 75% or the 95% gross income tests in any taxable year, we may nevertheless qualify as a REIT for that year if we satisfy the following requirements:

•

our failure to meet the test is due to reasonable cause and not due to willful neglect; and



•

after we identify the failure, we file a schedule describing each item of our gross income included in the 75% or 95% gross income tests for that taxable year.

It is impossible to state whether in all circumstances we would be entitled to the benefit of this relief provision for the 75% and 95% gross income tests. Even if this relief provision does apply, a 100% tax is imposed upon the greater of the amount by which we failed the 75% test or the amount by which we failed the 95% test, with adjustments, multiplied by a fraction intended to reflect our profitability. This relief provision applies to any failure of the applicable income tests, even if the failure first occurred in a year prior to the taxable year in which the failure was discovered.

        Asset Tests.    At the close of each quarter of each taxable year, we must also satisfy the following asset percentage tests in order to qualify as a REIT for federal income tax purposes:

•

At least 75% of our total assets must consist of real estate assets, cash and cash items, shares in other REITs, government securities and temporary investments of new capital (that is, stock or debt instruments purchased with proceeds of a stock offering or a public offering of our debt with a term of at least five years, but only for the one-year period commencing with our receipt of the offering proceeds).



•

Not more than 25% of our total assets may be represented by securities other than those securities that count favorably toward the preceding 75% asset test.

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•

Of the investments included in the preceding 25% asset class, the value of any one non-REIT issuer's securities that we own may not exceed 5% of the value of our total assets. In addition, we may not own more than 10% of the vote or value of any one non-REIT issuer's outstanding securities, unless the securities are "straight debt" securities or otherwise excepted as discussed below. Our stock and securities in a taxable REIT subsidiary are exempted from these 5% and 10% asset tests.



•

No more than 25% of our total assets may be represented by stock or securities of taxable REIT subsidiaries.

        When a failure to satisfy the above asset tests results from an acquisition of securities or other property during a quarter, the failure can be cured by disposition of sufficient nonqualifying assets within 30 days after the close of that quarter.

        In addition, if we fail the 5% value test or the 10% vote or value tests at the close of any quarter and we do not cure such failure within 30 days after the close of that quarter, that failure will nevertheless be excused if (a) the failure is de minimis and (b) within 6 months after the last day of the quarter in which we identify the failure, we either dispose of the assets causing the failure or otherwise satisfy the 5% value and 10% vote and value asset tests. For purposes of this relief provision, the failure will be "de minimis" if the value of the assets causing the failure does not exceed the lesser of (a) 1% of the total value of our assets at the end of the relevant quarter or (b) $10,000,000. If our failure is not de minimis, or if any of the other REIT asset tests have been violated, we may nevertheless qualify as a REIT if (a) we provide the IRS with a description of each asset causing the failure, (b) the failure was due to reasonable cause and not willful neglect, (c) we pay a tax equal to the greater of (1) $50,000 or (2) the highest rate of corporate tax imposed (currently 35%) on the net income generated by the assets causing the failure during the period of the failure and (d) within 6 months after the last day of the quarter in which we identify the failure, we either dispose of the assets causing the failure or otherwise satisfy all of the REIT asset tests. These relief provisions apply to any failure of the applicable asset tests, even if the failure first occurred in a year prior to the taxable year in which the failure was discovered.

        The IRC also provides an excepted securities safe harbor to the 10% value test that includes among other items (a) "straight debt" securities, (b) certain rental agreements in which payment is to be made in subsequent years, (c) any obligation to pay rents from real property, (d) securities issued by governmental entities that are not dependent in whole or in part on the profits of or payments from a nongovernmental entity and (e) any security issued by another REIT.

        We have maintained and will continue to maintain records of the value of our assets to document our compliance with the above asset tests, and intend to take actions as may be required to cure any failure to satisfy the tests within 30 days after the close of any quarter or within the six month periods described above.

        Annual Distribution Requirements.    In order to qualify for taxation as a REIT under the IRC, we are required to make annual distributions other than capital gain dividends to our shareholders in an amount at least equal to the excess of:

(A)

the sum of 90% of our "real estate investment trust taxable income," as defined in Section 857 of the IRC, computed by excluding any net capital gain and before taking into account any dividends paid deduction for which we are eligible, and 90% of our net income after tax, if any, from property received in foreclosure, over



(B)

the sum of our qualifying noncash income, e.g., imputed rental income or income from transactions inadvertently failing to qualify as like-kind exchanges.

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The distributions must be paid in the taxable year to which they relate, or in the following taxable year if declared before we timely file our federal income tax return for the earlier taxable year and if paid on or before the first regular distribution payment after that declaration. If a dividend is declared in October, November or December to shareholders of record during one of those months, and is paid during the following January, then for federal income tax purposes the dividend will be treated as having been both paid and received on December 31 of the prior taxable year. A distribution which is not pro rata within a class of our beneficial interests entitled to a distribution, or which is not consistent with the rights to distributions among our classes of beneficial interests, is a preferential distribution that is not taken into consideration for purposes of the distribution requirements, and accordingly the payment of a preferential distribution could affect our ability to meet the distribution requirements. Taking into account our distribution policies, including the dividend reinvestment plan we have adopted, we do not believe that we have made or will make any preferential distributions. The distribution requirements may be waived by the IRS if a REIT establishes that it failed to meet them by reason of distributions previously made to meet the requirements of the 4% excise tax discussed below. To the extent that we do not distribute all of our net capital gain and all of our real estate investment trust taxable income, as adjusted, we will be subject to federal income tax on undistributed amounts.

        In addition, we will be subject to a 4% nondeductible excise tax to the extent we fail within a calendar year to make required distributions to our shareholders of 85% of our ordinary income and 95% of our capital gain net income plus the excess, if any, of the "grossed up required distribution" for the preceding calendar year over the amount treated as distributed for that preceding calendar year. For this purpose, the term "grossed up required distribution" for any calendar year is the sum of our taxable income for the calendar year without regard to the deduction for dividends paid and all amounts from earlier years that are not treated as having been distributed under the provision. We will be treated as having sufficient earnings and profits to treat as a dividend any distribution by us up to the amount required to be distributed in order to avoid imposition of the 4% excise tax.

        If we do not have enough cash or other liquid assets to meet the 90% distribution requirements, we may find it necessary and desirable to arrange for new debt or equity financing to provide funds for required distributions in order to maintain our REIT status. We can provide no assurance that financing would be available for these purposes on favorable terms.

        We may be able to rectify a failure to pay sufficient dividends for any year by paying "deficiency dividends" to shareholders in a later year. These deficiency dividends may be included in our deduction for dividends paid for the earlier year, but an interest charge would be imposed upon us for the delay in distribution.

        In addition to the other distribution requirements above, to preserve our status as a REIT we are required to timely distribute all C corporation earnings and profits that we inherit from acquired corporations.

Our Relationship with GOV

        Following its initial public offering in 2009, we owned a significant minority, in excess of 10%, of GOV shares until 2013. We believe that GOV during these years qualified as a REIT under the IRC. In 2013, we sold all our GOV shares. For any of our taxable years in which GOV qualified as a REIT, our investment in GOV counted favorably as a qualifying REIT asset toward the REIT gross asset tests and our gains and dividends from GOV shares counted as qualifying income under the 75% and 95% gross income tests, all as described above. However, because we did not and could not control GOV's compliance with the federal income tax requirements for REIT qualification and taxation, we joined with GOV in filing a protective taxable REIT subsidiary election under Section 856(l) of the IRC, effective June 9, 2009, and we reaffirmed this protective election with GOV every January 1 thereafter

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through January 1, 2013. Pursuant to this protective taxable REIT subsidiary election, we believe that even if GOV was not a REIT for some reason, then it would instead have been considered one of our taxable REIT subsidiaries and treated in the manner described above. As one of our taxable REIT subsidiaries, we believe that GOV's failure to qualify as a REIT would not have jeopardized our own qualification as a REIT, even though we owned more than 10% of it.

Our Relationship with SIR

        Our formation of SIR, followed by SIR's issuance of its shares to the public in the SIR IPO, impacted our own REIT qualification and taxation under the IRC in the following manner.

        Formation of SIR.    Prior to the SIR IPO, SIR and its wholly owned subsidiaries were wholly owned by us. During this period, SIR and its subsidiaries were disregarded as entities separate from us for federal income tax purposes, either under the Treasury regulations issued under Section 7701 of the IRC or under the qualified REIT subsidiary rules of Section 856(i), all as described above. Accordingly, all assets, liabilities and items of income, deduction and credit of SIR and its subsidiaries during this period were treated as ours. Under the transaction agreement we entered into with SIR at the time of the SIR IPO, or the SIR transaction agreement, the federal income tax liabilities and federal income tax filings for SIR and its subsidiaries for this period are our responsibility.

        Our Taxation upon the SIR IPO.    When SIR first issued shares to persons other than us, or the SIR Effective Time, SIR ceased to be wholly owned by us. As a consequence, SIR and its subsidiaries ceased to be our disregarded entities for federal income tax purposes. Instead, at that time, SIR became regarded as a separate corporation that we believe satisfied the requirements for qualification and taxation as a REIT under the IRC, and its subsidiaries ceased to be treated as part of us and became disregarded entities treated as part of the newly separate SIR. In particular, there was a deemed exchange for federal income tax purposes at the time when SIR ceased to be wholly owned by us, or the SIR Deemed Exchange, and this SIR Deemed Exchange encompassed the following features:

•

The cash, assets and liabilities distributed from SIR to us prior to its issuance of shares in the SIR IPO were treated as cash, assets and liabilities retained by us and not included in the SIR Deemed Exchange.



•

The assets retained by SIR were treated as though contributed by us to SIR in the SIR Deemed Exchange.



•

The liabilities retained by SIR (other than SIR's $400.0 million demand promissory note issued to us and reimbursement obligations to us) were treated as liabilities of ours that were assumed by SIR in the SIR Deemed Exchange.



•

We were treated as receiving, as consideration in the SIR Deemed Exchange, (1) the SIR shares that we owned immediately after the SIR Effective Time, (2) the liabilities retained by SIR and treated as assumed by it from us in the SIR Deemed Exchange, plus (3) SIR's $400.0 million demand promissory note and reimbursement obligations to us.

Based on representations from us and from SIR, our counsel, Sullivan & Worcester LLP, opined that, because the initial SIR portfolio of properties was sufficiently diversified in terms of tenants, size, age, operating history and remaining lease length, Section 351(e) of the IRC should not apply, and accordingly the SIR Deemed Exchange should be governed by Sections 351 and 357 of the IRC, rather than Section 1001 of the IRC.

        However, because SIR's $400.0 million demand promissory note and reimbursement obligations to us were nonqualifying consideration under Section 351(b) of the IRC, we recognized almost all of our realized tax gains from the SIR Deemed Exchange, notwithstanding the application of Sections 351 and 357 instead of Section 1001. Also, because we owned more than 50% of SIR following the SIR IPO,

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most of our recognized tax gains were ordinary gains pursuant to Section 1239 of the IRC. Employing the valuation methodologies described below and based on the opinion of our counsel, Sullivan & Worcester LLP, that Sections 351 and 357 of the IRC applied to the SIR Deemed Exchange, our recognized tax gains from the SIR Deemed Exchange were approximately $69.3 million.

        In computing our aggregate amount realized, we were required to value for federal income tax purposes the SIR shares that we owned immediately after the SIR Effective Time. Under applicable judicial precedent, it is possible that the following two valuations may differ for federal income tax purposes: (1) the per share fair market value of the SIR shares that we owned immediately after the SIR Effective Time, versus (2) the average of the reported high and low trading prices for SIR shares in the public market on the date of the SIR Effective Time (i.e., $21.825 per share, which we call the "SIR Initial Price"). Because of the factual nature of the value of SIR shares, Sullivan & Worcester LLP is unable to render an opinion on the valuation of SIR shares generally, or on the valuation of the SIR shares that we owned immediately after the SIR Effective Time. Nevertheless, we believe that the per share fair market value of any and all SIR shares at the SIR Effective Time was properly valued at the SIR Initial Price for federal income tax purposes. Accordingly, the SIR Initial Price has been and will be used for all of our tax reporting, including for purposes of computing any gain we recognized in the SIR Deemed Exchange.

        Prior to the SIR Deemed Exchange, we held the assets comprising the SIR portfolio for investment with a view to long-term income production and capital appreciation, and the conversion of SIR into a separate REIT by means of the SIR IPO represented a new, unique opportunity to realize the value of that investment. Accordingly, we believe that any gains we recognized in the SIR portfolio as a result of the SIR Deemed Exchange were not subject to the 100% penalty tax of Section 857(b)(6) of the IRC, described above, applicable to gains from the disposition of inventory or other property held primarily for sale to customers. Moreover, we believe that any such recognized gains from the SIR Deemed Exchange qualified as gains from disposition of real property, and therefore counted favorably toward our compliance with the 75% and 95% gross income tests, as described above.

        If in a later year it is ultimately determined, contrary to our expectation, that we recognized additional gain or income as a result of the SIR Deemed Exchange, then we may be required to amend our tax reports, including those sent to our shareholders, and we will owe federal income tax on the undistributed gain and income unless we elect to pay a sufficient deficiency dividend to our shareholders. As discussed above, deficiency dividends may be included in our deduction for dividends paid for the year in which such gain or income is recognized, but an interest charge would be imposed upon us for the delay in distribution.

        Our Investment in SIR.    Following the SIR Effective Time, our aggregate initial tax basis in our SIR shares equaled our aggregate adjusted basis in the SIR portfolio immediately before the SIR Effective Time, minus the liabilities accrued for federal income tax purposes and assumed by SIR in the SIR Deemed Exchange, plus the gain we recognized in the SIR Deemed Exchange, minus the $400.0 million in respect of the demand promissory note, and minus the amount of SIR's reimbursement obligations to us.

        For any of our taxable years in which SIR qualifies as a REIT, our investment in SIR will count as a qualifying REIT asset toward the REIT gross asset tests and our gains and dividends from SIR shares will count as qualifying income under the 75% and 95% gross income tests, all as described above. However, because we cannot control SIR's compliance with the federal income tax requirements for REIT qualification and taxation, we joined with SIR in filing a protective taxable REIT subsidiary election under Section 856(l) of the IRC, effective March 13, 2012, and we have reaffirmed this protective election with SIR every January 1 thereafter, and may continue to do so, unless and until our ownership of SIR falls below 9.8%. Pursuant to this protective taxable REIT subsidiary election, we believe that even if SIR is not a REIT for some reason, then it would instead be considered one of our

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taxable REIT subsidiaries and treated in the manner described above. As one of our taxable REIT subsidiaries, we believe that SIR's failure to qualify as a REIT would not jeopardize our own qualification as a REIT, even though we own more than 10% of it.

        As discussed above, the SIR transaction agreement contains provisions that require SIR and us, due to our ongoing affiliation, to refrain from taking actions that may jeopardize the other's qualifications as a REIT under the IRC. For example, each of us is obligated to limit its investment in any tenant of the other, so that neither owns more than 4.9% of any such tenant, and each of us is obligated to cooperate reasonably with the other's requests motivated by REIT qualification and taxation.

Acquisition of C Corporations

        On July 17, 2008, we acquired a C corporation in a transaction where the C corporation was ultimately merged into our disregarded entity under Treasury regulations issued under Section 7701 of the IRC, all as described in Section 381(a) of the IRC. Thus, after the acquisition, all assets, liabilities and items of income, deduction and credit of the acquired corporation, and a proportionate share of the assets, liabilities and items of income, deduction and credit of the partnership in which the acquired corporation was a partner, have been treated as ours for purposes of the various REIT qualification tests described above. In addition, we generally were treated as the successor to the acquired corporate entity's federal income tax attributes, such as the entity's adjusted tax bases in its assets and its depreciation schedules; we were also treated as the successor to the acquired corporate entity's earnings and profits for federal income tax purposes.

        On October 7, 2010, we purchased office and industrial properties in Australia. In order to acquire the Australian properties, we acquired all of the beneficial interests of an Australian trust that owned those properties as its primary assets. Upon our acquisition, the acquired entity became either our qualified REIT subsidiary under Section 856(i) of the IRC or our disregarded entity (or, at a minimum, our almost wholly owned partnership) under Treasury regulations issued under Section 7701 of the IRC. Thus, after the 2010 acquisition, we have treated and will treat all assets, liabilities and items of income, deduction and credit of the acquired Australian trust as ours for purposes of the various REIT qualification tests described above. To address the possibility that the acquired trust was properly classified as a C corporation for federal tax purposes prior to our acquisition, we made an election under Section 338(g) of the IRC in respect of the acquired Australian trust. Accordingly, regardless of the Australian trust's proper federal tax classification prior to our acquisition, our initial federal income tax basis in the acquired assets is our cost for acquiring them, and we neither succeeded to any C corporation earnings and profits in this acquisition nor acquired any built-in gain in former C corporation assets.

        Built-in Gains from C Corporations.    As described above, notwithstanding our qualification and taxation as a REIT, we may still be subject to corporate taxation if we dispose of assets previously held by present or former C corporations. Specifically, if we acquire an asset from a corporation in a transaction in which our adjusted tax basis in the asset is determined by reference to the adjusted tax basis of that asset in the hands of a present or former C corporation, and if we subsequently recognize gain on the disposition of that asset during a specified period (generally ten years) beginning on the date on which the asset ceased to be owned by the C corporation, then we will generally pay tax at the highest regular corporate tax rate, currently 35%, on the lesser of (1) the excess, if any, of the asset's fair market value over its adjusted tax basis, each determined as of the time the asset ceased to be owned by the C corporation, or (2) our gain recognized in the disposition. Accordingly, any taxable disposition of an asset so acquired during the specified period (generally ten years) could be subject to tax under these rules. However, except as described below, we have not disposed, and have no present plan or intent to dispose, of any material assets acquired in such transactions.

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        For our 2013 taxable year, the general ten-year built-in gain recognition period was temporarily reduced to five years. Accordingly, although we sold assets in December 2013 that we had acquired in the July 17, 2008 acquisition, we did not incur any built-in gains tax liability because the sales occurred during 2013 and more than five years after the acquisition.

        To the extent of our gains in a taxable year that are subject to the built-in gains tax described above, net of any taxes paid on such gains with respect to that taxable year, our taxable dividends paid to you in the following year will be potentially eligible for treatment as qualified dividends that are taxed to our noncorporate U.S. shareholders at preferential rates.

        Earnings and Profits.    A REIT may not have any undistributed C corporation earnings and profits at the end of any taxable year. Upon the closing of our corporate acquisitions, we succeeded to the undistributed earnings and profits, if any, of the acquired and then disregarded corporate entities. Thus, we needed to distribute any such earnings and profits no later than the end of the applicable tax year. If we failed to do so, we would not qualify to be taxed as a REIT for that year and a number of years thereafter, unless we are able to rely on the relief provision described below.

        Although Sullivan & Worcester LLP is unable to render an opinion on factual determinations such as the amount of our undistributed earnings and profits, we have computed or retained accountants to compute the amount of undistributed earnings and profits that we inherited in our corporate acquisitions. Based on these calculations, we believe that we did not inherit any undistributed earnings and profits that remained undistributed at the end of the applicable tax year. However, there can be no assurance that the IRS would not, upon subsequent examination, propose adjustments to our calculation of the undistributed earnings and profits that we inherited, including adjustments that might be deemed necessary by the IRS as a result of its examination of the companies we acquired. In any such examination, the IRS might consider all taxable years of the acquired entities as open for review for purposes of its proposed adjustments. If it is subsequently determined that we had undistributed earnings and profits as of the end of the applicable tax year, we may be eligible for a relief provision similar to the "deficiency dividends" procedure described above. To utilize this relief provision, we would have to pay an interest charge for the delay in distributing the undistributed earnings and profits; in addition, we would be required to distribute to our shareholders, in addition to our other REIT distribution requirements, the amount of the undistributed earnings and profits less the interest charge paid.

Depreciation and Federal Income Tax Treatment of Leases

        Our initial tax bases in our assets will generally be our acquisition cost. We will generally depreciate our depreciable real property on a straight-line basis over 40 years and our personal property over the applicable shorter periods. These depreciation schedules may vary for properties that we acquire through tax-free or carryover basis acquisitions.

        We are entitled to depreciation deductions from our facilities only if we are treated for federal income tax purposes as the owner of the facilities. This means that the leases of the facilities must be classified for federal income tax purposes as true leases, rather than as sales or financing arrangements, and we believe this to be the case.

Like-Kind Exchanges

        In May 2008, we entered into a series of agreements to sell 48 medical office, clinic and biotech laboratory buildings to SNH; each of these properties was sold during 2008 or 2009 except for one, which is no longer subject to an agreement for sale. In June 2010, we entered into a series of agreements to sell 15 properties to GOV; each of these properties was sold during 2010. In November 2010, we entered into a series of agreements to sell 27 medical office, clinic and biotech laboratory buildings to SNH; each of these properties was sold during 2010 or 2011. On advice of counsel, we

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believe that each of the closings for our disposed properties should be viewed as a separate transaction for federal income tax purposes. We therefore entered into IRC Section 1031 like-kind exchanges for some, but not all, of the closings and reported those transactions as dispositions and exchanges separate from each other and from any cash sales. If, contrary to our view, the IRS recharacterizes our separate closings as one or more composite transactions, then some or all of our realized gain on the several dispositions that were intended to be like-kind exchanges may, contrary to our expectation of nonrecognition, be recognized in full. In that event, we may not have distributed all of our capital gain for 2008 through 2011, and we may owe federal income tax on the undistributed capital gain unless we elect to pay deficiency dividends to our shareholders. As discussed above, deficiency dividends may be included in our deduction for dividends paid for the year in which such gain is recognized, but an interest charge would be imposed upon us for the delay in distribution.

Taxation of U.S. Shareholders

        For noncorporate U.S. shareholders, to the extent that their total adjusted income does not exceed applicable thresholds, the maximum federal income tax rate for long-term capital gains and most corporate dividends is generally 15%. For those noncorporate U.S. shareholders whose total adjusted income exceeds the applicable thresholds, the maximum federal income tax rate for long-term capital gains and most corporate dividends is generally 20%. However, because we are not generally subject to federal income tax on the portion of our REIT taxable income distributed to our shareholders, dividends on our shares generally are not eligible for such preferential tax rates. As a result, our ordinary dividends continue to be taxed at the higher federal income tax rates applicable to ordinary income. However, the preferential federal income tax rates for long-term capital gains and for qualified dividends generally apply to:

(1)

long-term capital gains, if any, recognized on the disposition of our shares;



(2)

our distributions designated as long-term capital gain dividends (except to the extent attributable to real estate depreciation recapture, in which case the distributions are subject to a maximum 25% federal income tax rate);



(3)

our dividends attributable to dividends, if any, received by us from C corporations such as taxable REIT subsidiaries; and



(4)

our dividends to the extent attributable to income upon which we have paid federal corporate income tax.

        As long as we qualify as a REIT for federal income tax purposes, a distribution to our U.S. shareholders (including any constructive distributions on our common shares, on our series D cumulative convertible preferred shares, or on our series E cumulative redeemable preferred shares) that we do not designate as a capital gain dividend generally will be treated as an ordinary income dividend to the extent of our current or accumulated earnings and profits. Distributions made out of our current or accumulated earnings and profits that we properly designate as capital gain dividends generally will be taxed as long-term capital gains, as discussed below, to the extent they do not exceed our actual net capital gain for the taxable year. However, corporate shareholders may be required to treat up to 20% of any capital gain dividend as ordinary income under Section 291 of the IRC.

        In addition, we may elect to retain net capital gain income and treat it as constructively distributed. In that case:

(1)

we will be taxed at regular corporate capital gains tax rates on retained amounts;



(2)

each U.S. shareholder will be taxed on its designated proportionate share of our retained net capital gains as though that amount were distributed and designated a capital gain dividend;

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(3)

each U.S. shareholder will receive a credit for its designated proportionate share of the tax that we pay;



(4)

each U.S. shareholder will increase its adjusted basis in our shares by the excess of the amount of its proportionate share of these retained net capital gains over the U.S. shareholder's proportionate share of the tax that we pay; and



(5)

both we and our corporate shareholders will make commensurate adjustments in our respective earnings and profits for federal income tax purposes.

If we elect to retain our net capital gains in this fashion, we will notify our U.S. shareholders of the relevant tax information within 60 days after the close of the affected taxable year.

        If for any taxable year we designate capital gain dividends for U.S. shareholders, then a portion of the capital gain dividends we designate will be allocated to the holders of a particular class of shares on a percentage basis equal to the ratio of the amount of the total dividends paid or made available for the year to the holders of that class of shares to the total dividends paid or made available for the year to holders of all outstanding classes of our shares. We will similarly designate the portion of any capital gain dividend that is to be taxed to noncorporate U.S. shareholders at preferential maximum rates (including any capital gains attributable to real estate depreciation recapture that are subject to a maximum 25% federal income tax rate) so that the designations will be proportionate among all outstanding classes of our shares.

        Distributions in excess of current or accumulated earnings and profits will not be taxable to a U.S. shareholder to the extent that they do not exceed the shareholder's adjusted tax basis in the shareholder's shares, but will reduce the shareholder's basis in those shares. To the extent that these excess distributions exceed a U.S. shareholder's adjusted basis in our shares, they will be included in income as capital gain, with long-term gain generally taxed to noncorporate U.S. shareholders at preferential maximum rates. No U.S. shareholder may include on his federal income tax return any of our net operating losses or any of our capital losses.

        If a dividend is declared in October, November or December to shareholders of record during one of those months, and is paid during the following January, then for federal income tax purposes the dividend will be treated as having been both paid and received on December 31 of the prior taxable year. Also, items that are treated differently for regular and alternative minimum tax purposes are to be allocated between a REIT and its shareholders under Treasury regulations which are to be prescribed. It is possible that these Treasury regulations will require tax preference items to be allocated to our shareholders with respect to any accelerated depreciation or other tax preference items that we claim.

        A U.S. shareholder will generally recognize gain or loss equal to the difference between the amount realized and the shareholder's adjusted basis in our shares that are sold or exchanged. This gain or loss will be capital gain or loss, and will be long-term capital gain or loss if the shareholder's holding period in our shares exceeds one year. In addition, any loss upon a sale or exchange of our shares held for six months or less will generally be treated as a long-term capital loss to the extent of our long-term capital gain dividends paid on such shares during the holding period.

        In contrast to the typical redemption of preferred shares for cash only, discussed above, if a U.S. shareholder receives a number of our common shares as a result of a conversion or repurchase of series D cumulative convertible preferred shares or of series E cumulative redeemable preferred shares, then the transaction will be treated as a recapitalization. As such, the shareholder would recognize income or gain only to the extent of the lesser of (1) the excess, if any, of the value of the cash and common shares received over such shareholder's adjusted tax basis in, as applicable, its series D cumulative convertible preferred shares or its series E cumulative redeemable preferred shares surrendered or (2) the cash received. Any cash a shareholder receives, up to the amount of income or

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gain recognized, would generally be characterized as a dividend to the extent that a surrender of series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares, as applicable, to us for cash only would be taxable as a dividend, taking into account the surrendering shareholder's continuing actual or constructive ownership interest in our shares, if any, as discussed above, and the balance of the recognized amount, if any, will be gain. A U.S. shareholder's basis in its common shares received would be equal to the basis for, as applicable, the series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares surrendered, less any cash received plus any income or gain recognized. A U.S. shareholder's holding period in the common shares received would be the same as the holding period for, as applicable, the series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares surrendered. If, in addition to common shares, upon conversion or repurchase a U.S. shareholder receives rights or warrants to acquire our common shares or other of our securities, then the receipt of the rights or warrants may be taxable, and we encourage you to consult your tax advisor as to the consequences of the receipt of rights or warrants upon conversion or repurchase.

        A U.S. shareholder generally will not recognize any income, gain or loss upon conversion of series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares into common shares except with respect to cash, if any, received in lieu of a fractional common share. A U.S. shareholder's basis in its common shares received would be equal to the basis for, as applicable, the series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares surrendered, less any basis allocable to any fractional share exchanged for cash. A U.S. shareholder's holding period in the common shares received would be the same as the holding period for, as applicable, the series D cumulative convertible preferred shares or series E cumulative redeemable preferred shares surrendered. Any cash received in lieu of a fractional common share upon conversion will be treated as a payment in exchange for the fractional common share. Accordingly, receipt of cash in lieu of a fractional share generally will result in capital gain or loss, measured by the difference between the cash received for the fractional share and the adjusted tax basis attributable to the fractional share. If, in addition to common shares, upon conversion a U.S. shareholder receives rights or warrants to acquire our common shares or other of our securities, then the receipt of the rights or warrants may be taxable, and we encourage you to consult your tax advisor as to the consequences of the receipt of rights or warrants upon conversion.

        Effective July 1, 2010, our reverse stock split resulted in a one for four combination of our common shares. The reverse stock split was a tax-free recapitalization to us and to our U.S. shareholders pursuant to Section 368(a)(1)(E) of the IRC. Thus, none of our U.S. shareholders would have recognized gain or loss for federal income tax purposes as a result of exchanging pre-combination common shares for post-combination common shares pursuant to the reverse stock split. The holding period of the post-combination common shares received by a U.S. shareholder pursuant to the reverse stock split includes the holding period of the pre-combination common shares surrendered therefor, provided that the surrendered pre-combination common shares were held as a capital asset on the date of the split. The aggregate tax basis of the post-combination common shares received by a shareholder pursuant to the reverse stock split equals the aggregate tax basis of the pre-combination common shares surrendered therefor.

        U.S. shareholders who are individuals, estates or trusts are generally required to pay a 3.8% Medicare tax on their net investment income (including dividends on and gains from the sale or other disposition of our shares), or in the case of estates and trusts on their net investment income that is not distributed, in each case to the extent that their total adjusted income exceeds applicable thresholds.

        If a U.S. shareholder recognizes a loss upon a disposition of our shares in an amount that exceeds a prescribed threshold, it is possible that the provisions of Treasury regulations involving "reportable transactions" could apply, with a resulting requirement to separately disclose the loss-generating

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transaction to the IRS. These Treasury regulations are written quite broadly, and apply to many routine and simple transactions. A reportable transaction currently includes, among other things, a sale or exchange of our shares resulting in a tax loss in excess of (a) $10.0 million in any single year or $20.0 million in any combination of years in the case of our shares held by a C corporation or by a partnership with only C corporation partners or (b) $2.0 million in any single year or $4.0 million in any combination of years in the case of our shares held by any other partnership or an S corporation, trust or individual, including losses that flow through pass through entities to individuals. A taxpayer discloses a reportable transaction by filing IRS Form 8886 with its federal income tax return and, in the first year of filing, a copy of Form 8886 must be sent to the IRS's Office of Tax Shelter Analysis. The penalty for failing to disclose a reportable transaction is generally $10,000 in the case of a natural person and $50,000 in any other case.

        Noncorporate U.S. shareholders who borrow funds to finance their acquisition of our shares could be limited in the amount of deductions allowed for the interest paid on the indebtedness incurred. Under Section 163(d) of the IRC, interest paid or accrued on indebtedness incurred or continued to purchase or carry property held for investment is generally deductible only to the extent of the investor's net investment income. A U.S. shareholder's net investment income will include ordinary income dividend distributions received from us and, if an appropriate election is made by the shareholder, capital gain dividend distributions and qualified dividends received from us; however, distributions treated as a nontaxable return of the shareholder's basis will not enter into the computation of net investment income.

Taxation of Tax-Exempt Shareholders

        The rules governing the federal income taxation of tax-exempt entities are complex, and the following discussion is intended only as a summary of these rules. If you are a tax-exempt shareholder, we urge you to consult with your own tax advisor to determine the impact of federal, state, local and foreign tax laws, including any tax return filing and other reporting requirements, with respect to your investment in our shares.

        Subject to the pension-held REIT rules discussed below, our distributions made to shareholders that are tax-exempt pension plans, individual retirement accounts or other qualifying tax-exempt entities should not constitute unrelated business taxable income, provided that the shareholder has not financed its acquisition of our shares with "acquisition indebtedness" within the meaning of the IRC, that the shares are not otherwise used in an unrelated trade or business of the tax-exempt entity, and that, consistent with our present intent, we do not hold a residual interest in a real estate mortgage investment conduit.

        Tax-exempt pension trusts that own more than 10% by value of a "pension-held REIT" at any time during a taxable year may be required to treat a percentage of all dividends received from the pension-held REIT during the year as unrelated business taxable income. This percentage is equal to the ratio of:

(1)

the pension-held REIT's gross income derived from the conduct of unrelated trades or businesses, determined as if the pension-held REIT were a tax-exempt pension fund, less direct expenses related to that income, to



(2)

the pension-held REIT's gross income from all sources, less direct expenses related to that income,

except that this percentage shall be deemed to be zero unless it would otherwise equal or exceed 5%. A REIT is a pension-held REIT if:

•

the REIT is "predominantly held" by tax-exempt pension trusts; and

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•

the REIT would fail to satisfy the "closely held" ownership requirement discussed above if the stock or beneficial interests in the REIT held by tax-exempt pension trusts were viewed as held by tax-exempt pension trusts rather than by their respective beneficiaries.

A REIT is predominantly held by tax-exempt pension trusts if at least one tax-exempt pension trust owns more than 25% by value of the REIT's stock or beneficial interests, or if one or more tax-exempt pension trusts, each owning more than 10% by value of the REIT's stock or beneficial interests, own in the aggregate more than 50% by value of the REIT's stock or beneficial interests. Because of the share ownership concentration restrictions in our declaration of trust and bylaws, we believe that we are not and will not become a pension-held REIT. However, because our shares are publicly traded, we cannot completely control whether or not we are or will become a pension-held REIT.

        Social clubs, voluntary employee benefit associations, supplemental unemployment benefit trusts and qualified group legal services plans exempt from federal income taxation under Sections 501(c)(7), (c)(9), (c)(17) and (c)(20) of the IRC, respectively, are subject to different unrelated business taxable income rules, which generally will require them to characterize distributions from a REIT as unrelated business taxable income. In addition, these prospective investors should consult their own tax advisors concerning any "set aside" or reserve requirements applicable to them.

Taxation of Non-U.S. Shareholders

        The rules governing the United States federal income taxation of non-U.S. shareholders are complex, and the following discussion is intended only as a summary of these rules. If you are a non-U.S. shareholder, we urge you to consult with your own tax advisor to determine the impact of United States federal, state, local and foreign tax laws, including any tax return filing and other reporting requirements, with respect to your investment in our shares.

        In general, a non-U.S. shareholder will be subject to regular United States federal income tax in the same manner as a U.S. shareholder with respect to its investment in our shares if that investment is effectively connected with the non-U.S. shareholder's conduct of a trade or business in the United States (and, if provided by an applicable income tax treaty, is attributable to a permanent establishment or fixed base the non-U.S. shareholder maintains in the United States). In addition, a corporate non-U.S. shareholder that receives income that is or is deemed effectively connected with a trade or business in the United States may also be subject to the 30% branch profits tax under Section 884 of the IRC, which is payable in addition to regular United States federal corporate income tax. The balance of this discussion of the United States federal income taxation of non-U.S. shareholders addresses only those non-U.S. shareholders whose investment in our shares is not effectively connected with the conduct of a trade or business in the United States.

        A distribution by us to a non-U.S. shareholder that is not attributable to gain from the sale or exchange of a United States real property interest and that is not designated as a capital gain dividend will be treated as an ordinary income dividend to the extent that it is made out of current or accumulated earnings and profits. A distribution of this type will generally be subject to United States federal income tax and withholding at the rate of 30%, or at a lower rate if the non-U.S. shareholder has in the manner prescribed by the IRS demonstrated its entitlement to benefits under a tax treaty. In the case of any in kind distributions of property, we or other applicable withholding agents will have to collect the amount required to be withheld by reducing to cash for remittance to the IRS a sufficient portion of the property that the non-U.S. shareholder would otherwise receive, and the non-U.S. shareholder may bear brokerage or other costs for this withholding procedure. Because we cannot determine our current and accumulated earnings and profits until the end of the taxable year, withholding at the rate of 30% or applicable lower treaty rate will generally be imposed on the gross amount of any distribution to a non-U.S. shareholder that we make and do not designate as a capital gain dividend. Notwithstanding this withholding on distributions in excess of our current and

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accumulated earnings and profits, these distributions are a nontaxable return of capital to the extent that they do not exceed the non-U.S. shareholder's adjusted basis in our shares, and the nontaxable return of capital will reduce the adjusted basis in these shares. To the extent that distributions in excess of current and accumulated earnings and profits exceed the non-U.S. shareholder's adjusted basis in our shares, the distributions will give rise to tax liability if the non-U.S. shareholder would otherwise be subject to tax on any gain from the sale or exchange of these shares, as discussed below. A non-U.S. shareholder may seek a refund from the IRS of amounts withheld on distributions to him in excess of our current and accumulated earnings and profits.

        From time to time, some of our distributions may be attributable to the sale or exchange of United States real property interests. However, capital gain dividends that are received by a non-U.S. shareholder, as well as dividends attributable to our sales of United States real property interests, will be subject to the taxation and withholding regime applicable to ordinary income dividends and the branch profits tax will not apply, provided that (1) these dividends are received with respect to a class of shares that is "regularly traded" on a domestic "established securities market" such as the NYSE, both as defined by applicable Treasury regulations, and (2) the non-U.S. shareholder does not own more than 5% of that class of shares at any time during the one-year period ending on the date of distribution of the applicable capital gain and United States real property interest dividends. If both of these provisions are satisfied, qualifying non-U.S. shareholders will not be subject to withholding either on capital gain dividends or on dividends that are attributable to our sales of United States real property interests as though those amounts were effectively connected with a United States trade or business, and qualifying non-U.S. shareholders will not be required to file United States federal income tax returns or pay branch profits tax in respect of these dividends. Instead, these dividends will be subject to United States federal income tax and withholding as ordinary dividends, currently at a 30% tax rate unless reduced by an applicable treaty, as discussed below. Although there can be no assurance in this regard, we believe that our common shares and each class of our preferred shares have been and will remain "regularly traded" on a domestic "established securities market" within the meaning of applicable Treasury regulations; however, we can provide no assurance that our shares will continue to be "regularly traded" on a domestic "established securities market" in future taxable years.

        Except as discussed above, for any year in which we qualify as a REIT, distributions that are attributable to gain from the sale or exchange of a United States real property interest are taxed to a non-U.S. shareholder as if these distributions were gains effectively connected with a trade or business in the United States conducted by the non-U.S. shareholder. Accordingly, a non-U.S. shareholder that does not qualify for the special rule above will be taxed on these amounts at the normal capital gain and other tax rates applicable to a U.S. shareholder, subject to any applicable alternative minimum tax and to a special alternative minimum tax in the case of nonresident alien individuals; such a non-U.S. shareholder will be required to file a United States federal income tax return reporting these amounts, even if applicable withholding is imposed as described below; and such a non-U.S. shareholder that is also a corporation may owe the 30% branch profits tax under Section 884 of the IRC in respect of these amounts. We or other applicable withholding agents will be required to withhold from distributions to such non-U.S. shareholders, and remit to the IRS, 35% of the maximum amount of any distribution that could be designated as a capital gain dividend. In addition, for purposes of this withholding rule, if we designate prior distributions as capital gain dividends, then subsequent distributions up to the amount of the designated prior distributions will be treated as capital gain dividends. The amount of any tax withheld is creditable against the non-U.S. shareholder's United States federal income tax liability, and the non-U.S. shareholder may file for a refund from the IRS of any amount of withheld tax in excess of that tax liability.

        A special "wash sale" rule applies to a non-U.S. shareholder who owns any class of our shares if (1) the non-U.S. shareholder owns more than 5% of that class of shares at any time during the one-year period ending on the date of the distribution described below, or (2) that class of our shares

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is not, within the meaning of applicable Treasury regulations, "regularly traded" on a domestic "established securities market" such as the NYSE. Although there can be no assurance in this regard, we believe that our common shares and each class of our preferred shares have been and will remain "regularly traded" on a domestic "established securities market" within the meaning of applicable Treasury regulations, all as discussed above; however, we can provide no assurance that our shares will continue to be "regularly traded" on a domestic "established securities market" in future taxable years. We thus anticipate this wash sale rule to apply, if at all, only to a non-U.S. shareholder that owns more than 5% of either our common shares or any class of our preferred shares. Such a non-U.S. shareholder will be treated as having made a "wash sale" of our shares if it (1) disposes of an interest in our shares during the 30 days preceding the ex-dividend date of a distribution by us that, but for such disposition, would have been treated by the non-U.S. shareholder in whole or in part as gain from the sale or exchange of a United States real property interest, and then (2) acquires or enters into a contract to acquire a substantially identical interest in our shares, either actually or constructively through a related party, during the 61-day period beginning 30 days prior to the ex-dividend date. In the event of such a wash sale, the non-U.S. shareholder will have gain from the sale or exchange of a United States real property interest in an amount equal to the portion of the distribution that, but for the wash sale, would have been a gain from the sale or exchange of a United States real property interest. As discussed above, a non-U.S. shareholder's gain from the sale or exchange of a United States real property interest can trigger increased United States taxes, such as the branch profits tax applicable to non-U.S. corporations, and increased United States tax filing requirements.

        If for any taxable year we designate capital gain dividends for our shareholders, then a portion of the capital gain dividends we designate will be allocated to the holders of a particular class of shares on a percentage basis equal to the ratio of the amount of the total dividends paid or made available for the year to the holders of that class of shares to the total dividends paid or made available for the year to holders of all outstanding classes of our shares.

        Tax treaties may reduce the withholding obligations on our distributions. Under some treaties, however, rates below 30% that are applicable to ordinary income dividends from United States corporations may not apply to ordinary income dividends from a REIT or may apply only if the REIT meets specified additional conditions. A non-U.S. shareholder must generally use an applicable IRS Form W-8, or substantially similar form, to claim tax treaty benefits. If the amount of tax withheld with respect to a distribution to a non-U.S. shareholder exceeds the shareholder's United States federal income tax liability with respect to the distribution, the non-U.S. shareholder may file for a refund of the excess from the IRS. The 35% withholding tax rate discussed above on some capital gain dividends corresponds to the maximum income tax rate applicable to corporate non-U.S. shareholders but is higher than the current preferential maximum rates on capital gains generally applicable to noncorporate non-U.S. shareholders. Treasury regulations also provide special rules to determine whether, for purposes of determining the applicability of a tax treaty, our distributions to a non-U.S. shareholder that is an entity should be treated as paid to the entity or to those owning an interest in that entity and whether the entity or its owners are entitled to benefits under the tax treaty. In the case of any in kind distributions of property, we or other applicable withholding agents will have to collect the amount required to be withheld by reducing to cash for remittance to the IRS a sufficient portion of the property that the non-U.S. shareholder would otherwise receive, and the non-U.S. shareholder may bear brokerage or other costs for this withholding procedure.

        Non-U.S. shareholders should generally be able to treat amounts we designate as retained but constructively distributed capital gains in the same manner as actual distributions of capital gain dividends by us. In addition, a non-U.S. shareholder should be able to offset as a credit against its federal income tax liability the proportionate share of the tax paid by us on such retained but constructively distributed capital gains. A non-U.S. shareholder may file for a refund from the IRS for

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the amount that the non-U.S. shareholder's proportionate share of tax paid by us exceeds its federal income tax liability on the constructively distributed capital gains.

        If our shares are not "United States real property interests" within the meaning of Section 897 of the IRC, then a non-U.S. shareholder's gain on sale of these shares (including for this purpose a conversion of our series D cumulative convertible preferred shares or our series E cumulative redeemable preferred shares into common shares) generally will not be subject to United States federal income taxation, except that a nonresident alien individual who was in the United States for 183 days or more during the taxable year may be subject to a 30% tax on this gain. Our shares will not constitute a United States real property interest if we are a "domestically controlled REIT." A domestically controlled REIT is a REIT in which at all times during the preceding five-year period less than 50% of the fair market value of the outstanding shares was directly or indirectly held by foreign persons. We believe that we have been and will remain a domestically controlled REIT and thus a non-U.S. shareholder's gain on a sale of our shares will not be subject to United States federal income taxation. However, because our shares are publicly traded, we can provide no assurance that we have been or will remain a domestically controlled REIT. If we are not a domestically controlled REIT, a non-U.S. shareholder's gain on sale of our shares will not be subject to United States federal income taxation as a sale of a United States real property interest, if that class of shares is "regularly traded," as defined by applicable Treasury regulations, on an established securities market like the NYSE, and the non-U.S. shareholder has at all times during the preceding five years owned 5% or less by value of that class of shares. In this regard, because the shares held by others may be redeemed, and in the case of the series D cumulative convertible preferred shares, are convertible, a non-U.S. shareholder's percentage interest in a class of our shares may increase even if it acquires no additional shares in that class. If the gain on the sale of our shares were subject to United States federal income taxation, the non-U.S. shareholder will generally be subject to the same treatment as a U.S. shareholder with respect to its gain and will be required to file a United States federal income tax return reporting that gain; in addition, a corporate non-U.S. shareholder might owe branch profits tax under Section 884 of the IRC. A purchaser of our shares from a non-U.S. shareholder will not be required to withhold on the purchase price if the purchased shares are regularly traded on an established securities market or if we are a domestically controlled REIT. Otherwise, a purchaser of our shares from a non-U.S. shareholder may be required to withhold 10% of the purchase price paid to the non-U.S. shareholder and to remit the withheld amount to the IRS.

        Effective July 1, 2010, our reverse stock split resulted in a one for four combination of our common shares. The reverse stock split was a tax-free recapitalization to us pursuant to Section 368(a)(1)(E) of the IRC. Provided that we were at the time of the reverse stock split a domestically controlled REIT, as discussed above, or alternatively that our common shares at the time of the reverse stock split were "regularly traded" and a non-U.S. shareholder at all times during the preceding five years owned 5% or less by value of our common shares, each as discussed above, then the reverse stock split was also a tax-free recapitalization to the non-U.S. shareholder pursuant to Section 368(a)(1)(E) of the IRC. In that event, the non-U.S. shareholder would not have recognized gain or loss for federal income tax purposes as a result of exchanging pre-combination common shares for post-combination common shares pursuant to the reverse stock split; the holding period of the post-combination common shares received by a non-U.S. shareholder pursuant to the reverse stock split would include the holding period of the pre-combination common shares surrendered therefor, provided that the surrendered pre-combination common shares were held as a capital asset on the date of the split; and, the aggregate tax basis of the post-combination common shares received by a non-U.S. shareholder pursuant to the reverse stock split would equal the aggregate tax basis of the pre-combination common shares surrendered therefor. However, at the time of the reverse stock split, if we were not a domestically controlled REIT and if either our common shares were not "regularly traded" or a non-U.S. shareholder exceeded the above 5% ownership limitation, then the non-U.S.

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shareholder may have been required to file a United States federal income tax return for the taxable year of the reverse stock split in order to avoid recognition of gain on the reverse stock split.

Withholding and Information Reporting

        Information reporting and backup withholding may apply to distributions or proceeds paid to our shareholders under the circumstances discussed below. The backup withholding rate is currently 28%. Amounts withheld under backup withholding are generally not an additional tax and may be refunded by the IRS or credited against the shareholder's federal income tax liability. In the case of any in kind distributions of property by us to a shareholder, we or other applicable withholding agents will have to collect any applicable backup withholding by reducing to cash for remittance to the IRS a sufficient portion of the property that our shareholder would otherwise receive, and the shareholder may bear brokerage or other costs for this withholding procedure.

        A U.S. shareholder will be subject to backup withholding when it receives distributions on our shares or proceeds upon the sale, exchange, redemption, retirement or other disposition of our shares, unless the U.S. shareholder properly executes, or has previously properly executed, under penalties of perjury an IRS Form W-9 or substantially similar form that:

•

provides the U.S. shareholder's correct taxpayer identification number; and



•

certifies that the U.S. shareholder is exempt from backup withholding because it comes within an enumerated exempt category, it has not been notified by the IRS that it is subject to backup withholding, or it has been notified by the IRS that it is no longer subject to backup withholding.

If the U.S. shareholder has not provided and does not provide its correct taxpayer identification number on an IRS Form W-9 or substantially similar form, it may be subject to penalties imposed by the IRS, and we or other applicable withholding agents may have to withhold a portion of any distributions or proceeds paid to such U.S. shareholder. Unless the U.S. shareholder has established on a properly executed IRS Form W-9 or substantially similar form that it comes within an enumerated exempt category, distributions or proceeds on our shares paid to it during the calendar year, and the amount of tax withheld, if any, will be reported to it and to the IRS.

        Distributions on our shares to a non-U.S. shareholder during each calendar year and the amount of tax withheld, if any, will generally be reported to the non-U.S. shareholder and to the IRS. This information reporting requirement applies regardless of whether the non-U.S. shareholder is subject to withholding on distributions on our shares or whether the withholding was reduced or eliminated by an applicable tax treaty. Also, distributions paid to a non-U.S. shareholder on our shares may be subject to backup withholding, unless the non-U.S. shareholder properly certifies its non-U.S. shareholder status on an IRS Form W-8 or substantially similar form in the manner described above. Similarly, information reporting and backup withholding will not apply to proceeds a non-U.S. shareholder receives upon the sale, exchange, redemption, retirement or other disposition of our shares, if the non-U.S. shareholder properly certifies its non-U.S. shareholder status on an IRS Form W-8 or substantially similar form. Even without having executed an IRS Form W-8 or substantially similar form, however, in some cases information reporting and backup withholding will not apply to proceeds that a non-U.S. shareholder receives upon the sale, exchange, redemption, retirement or other disposition of our shares if the non-U.S. shareholder receives those proceeds through a broker's foreign office.

        Increased reporting obligations are scheduled to be imposed on non-United States financial institutions and other non-United States entities for purposes of identifying accounts and investments held directly or indirectly by United States persons. The failure to comply with these additional information reporting, certification and other specified requirements could result in withholding tax

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being imposed on payments of dividends and sales proceeds to applicable shareholders or intermediaries. Specifically, a 30% withholding tax is imposed on dividends on and gross proceeds from the sale or other disposition of our shares paid to a foreign financial institution or to a foreign nonfinancial entity, unless (1) the foreign financial institution undertakes applicable diligence and reporting obligations or (2) the foreign nonfinancial entity either certifies it does not have any substantial United States owners or furnishes identifying information regarding each substantial United States owner. In addition, if the payee is a foreign financial institution, it generally must enter into an agreement with the United States Department of the Treasury that requires, among other things, that it undertake to identify accounts held by applicable United States persons or United States-owned foreign entities, annually report specified information about such accounts, and withhold 30% on payments to noncertified holders. Pursuant to IRS guidance, such withholding will apply only to dividends paid after June 30, 2014 and to other "withholdable payments" (including payments of gross proceeds from a sale or other disposition of our shares) made after December 31, 2016. If you hold our shares through a non-United States intermediary or if you are a non-United States person, we urge you to consult your own tax advisor regarding foreign account tax compliance.

Other Tax Consequences

        Our tax treatment and that of our shareholders may be modified by legislative, judicial or administrative actions at any time, which actions may be retroactive in effect. The rules dealing with federal income taxation are constantly under review by Congress, the IRS and the United States Department of the Treasury, and statutory changes, new regulations, revisions to existing regulations and revised interpretations of established concepts are issued frequently. Likewise, the rules regarding taxes other than federal income taxes may also be modified. No prediction can be made as to the likelihood of passage of new tax legislation or other provisions, or the direct or indirect effect on us and our shareholders. Revisions to tax laws and interpretations of these laws could adversely affect the tax or other consequences of an investment in our shares. We and our shareholders may also be subject to taxation by state, local or other jurisdictions, including those in which we or our shareholders transact business or reside. These tax consequences may not be comparable to the federal income tax consequences discussed above.

ERISA PLANS, KEOGH PLANS AND INDIVIDUAL RETIREMENT ACCOUNTS

General Fiduciary Obligations

        Fiduciaries of a pension, profit-sharing or other employee benefit plan subject to Title I of the Employee Retirement Income Security Act of 1974, as amended, or ERISA, must consider whether:

•

their investment in our shares satisfies the diversification requirements of ERISA;



•

the investment is prudent in light of possible limitations on the marketability of our shares;



•

they have authority to acquire our shares under the applicable governing instrument and Title I of ERISA; and



•

the investment is otherwise consistent with their fiduciary responsibilities.

        Trustees and other fiduciaries of an ERISA plan may incur personal liability for any loss suffered by the plan on account of a violation of their fiduciary responsibilities. In addition, these fiduciaries may be subject to a civil penalty of up to 20% of any amount recovered by the plan on account of a violation. Fiduciaries of any individual retirement account or annuity, or IRA, Roth IRA, tax-favored account (such as an Archer MSA, Coverdell education savings account or health savings account), Keogh Plan or other qualified retirement plan not subject to Title I of ERISA, or non-ERISA plans, should consider that the plan may only make investments that are authorized by the appropriate governing instrument.

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        Fiduciaries considering an investment in our securities should consult their own legal advisors if they have any concern as to whether the investment is consistent with the foregoing criteria or is otherwise appropriate. The sale of our securities to an ERISA or non-ERISA plan is in no respect a representation by us or any underwriter of the securities that the investment meets all relevant legal requirements with respect to investments by plans generally or any particular plan, or that the investment is appropriate for plans generally or any particular plan.

Prohibited Transactions

        Fiduciaries of ERISA plans and persons making the investment decision for an IRA or other non-ERISA plan should consider the application of the prohibited transaction provisions of ERISA and the IRC in making their investment decision. Sales and other transactions between an ERISA or non-ERISA plan, and persons related to it, are prohibited transactions. The particular facts concerning the sponsorship, operations and other investments of an ERISA plan or non-ERISA plan may cause a wide range of other persons to be treated as disqualified persons or parties in interest with respect to it. A prohibited transaction, in addition to imposing potential personal liability upon fiduciaries of ERISA plans, may also result in the imposition of an excise tax under the IRC or a penalty under ERISA upon the disqualified person or party in interest with respect to the plan. If the disqualified person who engages in the transaction is the individual on behalf of whom an IRA or Roth IRA is maintained or his beneficiary, the IRA or Roth IRA may lose its tax-exempt status and its assets may be deemed to have been distributed to the individual in a taxable distribution on account of the prohibited transaction, but no excise tax will be imposed. Fiduciaries considering an investment in our securities should consult their own legal advisors as to whether the ownership of our securities involves a prohibited transaction.

"Plan Assets" Considerations

        The United States Department of Labor has issued a regulation defining "plan assets." The regulation generally provides that when an ERISA or non-ERISA plan acquires a security that is an equity interest in an entity and that security is neither a "publicly offered security" nor a security issued by an investment company registered under the Investment Company Act of 1940, as amended, the ERISA plan's or non-ERISA plan's assets include both the equity interest and an undivided interest in each of the underlying assets of the entity, unless it is established either that the entity is an operating company or that equity participation in the entity by benefit plan investors is not significant.

        Each class of our shares (that is, our common shares and any class of preferred shares that we have issued or may issue) must be analyzed separately to ascertain whether it is a publicly offered security. The regulation defines a publicly offered security as a security that is "widely held," "freely transferable" and either part of a class of securities registered under the Exchange Act, or sold under an effective registration statement under the Securities Act of 1933, as amended, provided the securities are registered under the Exchange Act within 120 days after the end of the fiscal year of the issuer during which the offering occurred. Each class of our outstanding shares has been registered under the Exchange Act within the necessary time frame to satisfy the foregoing condition.

        The regulation provides that a security is "widely held" only if it is part of a class of securities that is owned by 100 or more investors independent of the issuer and of one another. However, a security will not fail to be "widely held" because the number of independent investors falls below 100 subsequent to the initial public offering as a result of events beyond the issuer's control. We believe our common shares and our preferred shares have been and will remain widely held, and we expect the same to be true of any additional class of preferred shares that we may issue, but we can give no assurances in this regard.

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        The regulation provides that whether a security is "freely transferable" is a factual question to be determined on the basis of all relevant facts and circumstances. The regulation further provides that, where a security is part of an offering in which the minimum investment is $10,000 or less, some restrictions on transfer ordinarily will not, alone or in combination, affect a finding that these securities are freely transferable. The restrictions on transfer enumerated in the regulation as not affecting that finding include:

•

any restriction on or prohibition against any transfer or assignment that would result in a termination or reclassification for federal or state tax purposes, or would otherwise violate any state or federal law or court order;



•

any requirement that advance notice of a transfer or assignment be given to the issuer and any requirement that either the transferor or transferee, or both, execute documentation setting forth representations as to compliance with any restrictions on transfer that are among those enumerated in the regulation as not affecting free transferability, including those described in the preceding clause of this sentence;



•

any administrative procedure that establishes an effective date, or an event prior to which a transfer or assignment will not be effective; and



•

any limitation or restriction on transfer or assignment that is not imposed by the issuer or a person acting on behalf of the issuer.

        We believe that the restrictions imposed under our declaration of trust and bylaws on the transfer of shares do not result in the failure of our shares to be "freely transferable." Furthermore, we believe that there exist no other facts or circumstances limiting the transferability of our shares that are not included among those enumerated as not affecting their free transferability under the regulation, and we do not expect or intend to impose in the future, or to permit any person to impose on our behalf, any limitations or restrictions on transfer that would not be among the enumerated permissible limitations or restrictions.

        Assuming that each class of our shares will be "widely held" and that no other facts and circumstances exist that restrict transferability of these shares, we have received an opinion of our counsel, Sullivan & Worcester LLP, that our shares will not fail to be "freely transferable" for purposes of the regulation due to the restrictions on transfer of our shares under our declaration of trust and bylaws and that under the regulation each class of our currently outstanding shares is publicly offered and our assets will not be deemed to be "plan assets" of any ERISA plan or non-ERISA plan that acquires our shares in a public offering. This opinion is conditioned upon certain assumptions and representations, as discussed above in "Federal Income Tax Considerations—Taxation as a REIT."

RISK FACTORS

Item 1A.    Risk Factors.

        Our business faces many risks. The risks described below may not be the only risks we face but are the risks we know of that we believe may be material at this time. Additional risks that we do not yet know of, or that we currently think are immaterial, may also impair our business operations or financial results. If any of the events or circumstances described in the following risks occurs, our business, financial condition or results of operations could suffer and the trading price of our securities could decline. Investors and prospective investors should consider the following risks and the information contained under the heading "Warning Concerning Forward Looking Statements" before deciding whether to invest in our securities.

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Risks Related to the activities of Related Fund Management, LLC, Corvex Management LP, or together, Related/Corvex

The Related/Corvex consent solicitation to remove of all of our Trustees without cause and related activities may disrupt our business and operations, give rise to preferred shareholder conversion rights and events of default under certain material agreements, affect our ability to pay distributions, repurchase shares, borrow money and execute our business plan, and have other effects which may adversely affect us.

        If our entire Board of Trustees is removed as a result of the Related/Corvex consent solicitation, such removal may, among other things, disrupt our business and operations, give rise to preferred shareholder conversion rights and events of default under certain material agreements, affect our ability to pay distributions, repurchase shares, borrow money and execute our business plan, and have other effects which may adversely affect us. For example:

•

considering and responding to the Related/Corvex actions and allegations has been, and may continue to be, disruptive, costly and time consuming, and a significant distraction for our management;



•

the removal of our entire Board of Trustees as a result of the Related/Corvex consent solicitation would constitute an event of default under our revolving credit facility and term loan agreement and may also constitute an event of default under certain mortgage loans, which could have material adverse consequences, including triggering limitations under our loan agreements on our ability to pay distributions, repurchase shares or borrow money, possible acceleration of amounts outstanding under our loan agreements and possible cross defaults under, and acceleration of, our other debt obligations;



•

the removal of our entire Board of Trustees as a result of the Related/Corvex consent solicitation would constitute a fundamental change under our 6.5% series D cumulative convertible preferred shares giving holders of such shares the option to convert these shares into common shares at a ratio based on 98% of the average closing market price for a period before such removal is effective, unless we repurchase these shares for their par value plus accrued and unpaid distributions;



•

the removal of our entire Board of Trustees as a result of the Related/Corvex consent solicitation may constitute a "change of control" under certain of our other material agreements, which could have material adverse consequences under such agreements;



•

certain actions proposed by Related/Corvex, such as increasing our debt and paying distributions to shareholders or repurchasing our equity securities may result in the downgrading of our debt ratings and loss of our investment grade debt rating;



•

the removal of our entire Board of Trustees and the calling of a special meeting for the election of replacement Trustees will leave us without any Trustees to manage our business and affairs and to authorize the payment of future distributions to our common and preferred shareholders until a special meeting is held and replacement Trustees are elected and qualified;



•

perceived uncertainties as to our future direction, including, but not limited to, uncertainties related to the composition of our Board of Trustees and our management, as well as our future business plans, may result in the loss of potential business, opportunities and loss of bargaining power when leasing, disposing or acquiring properties;



•

the termination of our business or property management agreements with RMR and internalization of our management, as proposed by Related/Corvex, may lead to significantly increased costs and expenses and material disruption to our business;

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•

the removal of our entire Board of Trustees as a result of the Related/Corvex consent solicitation may adversely affect our ability to create additional value for our shareholders by effectively executing our business plan;



•

the removal of our entire Board of Trustees as a result of the Related/Corvex consent solicitation may make it difficult for us to comply with federal securities laws, including our obligation to file periodic reports and maintain effective internal control over financial reporting and disclosure controls and procedures, which may affect our liquidity;



•

the removal of our entire Board of Trustees as a result of the Related/Corvex consent solicitation may give rise to our violation of the rules and regulations of the SEC requiring that we have an independent Audit Committee and certain NYSE continued listing requirements, which may result in the SEC or NYSE taking enforcement action against us, including action by the NYSE to delist our common shares and other publicly traded securities;



•

the actions taken by Related/Corvex have created an environment conducive to follow-on litigation, which serves as a further distraction to our management and may require us to incur significant costs. Costs associated with the Related/Corvex activities, including their consent solicitation, related actions and litigation, have been, and may continue to be, substantial. Further, if determined adversely, such litigation could materially and adversely affect us; and



•

the removal of our entire Board of Trustees as a result of the Related/Corvex consent solicitation may facilitate the acquisition of control of us or other transactions on terms that are not in the best interests of the Company and our shareholders.

        You should also not assume that any actions or proposed actions described by Related/Corvex in the materials they have filed with the SEC will be taken, and you should not necessarily ascribe incremental value to our common shares as a result of the possibility of such actions.

        Additional information about the risks which may arise from the activities by Related/Corvex is included in, and incorporated herein by reference to, our Definitive Consent Revocation Statement filed with the SEC on Schedule 14A on January 29, 2014. We continue to review the possible implications of the Related/Corvex activities and may identify additional risks and uncertainties created by the Related/Corvex actions.

We are a party to numerous legal proceedings, which could distract our Board of Trustees and management, affect the Related/Corvex consent solicitation and/or adversely affect us.

        As noted below in Item 3 "Legal Proceedings", we, along with RMR, our officers and current and former Trustees, have been named as defendants in a number of complaints seeking monetary damages and declaratory and injunctive relief, including, among other things, complaints seeking to invalidate certain provisions of our bylaws and challenging the equity offering we completed in 2013. Additional claims may be filed against us in connection with any action we may or may not take, including any equity or debt financing we may undertake, any sales of our assets, past and future amendments to our bylaws, our Board of Trustees' response to actions by Related/Corvex or others and other actions by our Board of Trustees and by us. The results of litigation are difficult to predict and we can provide no assurance that our legal conclusions or positions will be upheld. Moreover, claims of this nature present a risk of protracted litigation, incurrence of significant attorneys' fees, costs and expenses, and diversion of management's attention from the operation of our business. Adverse rulings in the legal proceedings noted in Item 3 "Legal Proceedings" could have a material adverse effect on our financial results and condition and cause substantial reputational harm and/or a decline in the market price of our shares. In addition, we have agreed to indemnify our present or former Trustees or officers who are made or threatened to be made parties to a legal proceeding by reason of their service in that capacity and have also agreed to indemnify RMR for claims brought against RMR in its capacity as our business and

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property manager. We do not have insurance to cover certain of these potential claims and indemnification obligations and may incur significant costs in connection with these legal proceedings or our indemnification obligations.

Risks Related to Our Business

If the current unemployment rate in the United States worsens, the occupancy and rents at our properties may decline.

        If the current unemployment rate in the United States worsens, the demand to lease office and industrial space may decline. Reductions in tenant demand to lease space are likely to result in reduced occupancy and rents at our properties. Many of our operating costs, such as utilities, real estate taxes, insurance, etc., are fixed. If our rents decline our income and cash flow available for distribution will decline and we may become unable to maintain our current rate of distributions to our shareholders.

The U.S. economy has recently experienced a recession and while the economy grew modestly in 2013, we do not know if the economy will continue to improve or if it may decline. As a result, some of our tenants may become unable to pay our rents and the values of our properties may decline.

        The U.S. economy has recently experienced a recession and while the economy grew modestly in 2013, we do not know if the economy will continue to improve or if it may decline. If current general economic conditions persist or worsen, our business, prospects, financial condition, liquidity, results of operations and ability to meet our obligations and make or sustain distributions to our shareholders may be materially and adversely affected, including as follows:

•

our tenants may become unable or unwilling to pay our rents;



•

the demand for leased office and industrial space across the country may decline, and the rents we can charge when leases are renewed or new leases are entered may be lower than the rents we now charge;



•

we may be unable to lease our properties which become vacant as our leases expire or if our tenants default;



•

the market values of our properties may decline; and



•

access to capital markets may become difficult, expensive or impossible, and our ability to obtain debt or equity capital to fund our operations, meet our obligations, purchase additional properties or otherwise conduct our business may be materially and adversely affected or eliminated.

We may be unable to access the capital necessary to repay our debts, invest in our properties or fund acquisitions.

        To retain our status as a REIT, we are required to distribute at least 90% of our annual REIT taxable income (excluding capital gains) and satisfy a number of organizational and operational requirements to which REITs are subject. Accordingly, we generally will not be able to retain sufficient cash from operations to repay debts, invest in our properties or fund acquisitions. Our business and growth strategies depend, in part, upon our ability to raise additional capital at reasonable costs to repay our debts, invest in our properties and fund acquisitions. Because of the volatility in the availability of capital to businesses on a global basis and the increased volatility in most debt and equity markets generally, our ability to raise reasonably priced capital is not guaranteed; we may be unable to raise reasonably priced capital because of reasons related to our business or for reasons beyond our control, such as market conditions. If we are unable to raise reasonably priced capital, our business and growth strategies may fail and we may be unable to remain a REIT.

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We are currently dependent upon economic conditions in our two core business segments: CBD properties and suburban properties.

        For the quarter ended December 31, 2013, excluding properties classified in discontinued operations, we received approximately 69.3% of our total revenues from properties classified in our CBD segment and approximately 30.7% of our total revenues from properties classified in our suburban segment. Unless the economic conditions return to pre-recession levels, particularly in our suburban segment, we may experience reduced demand from tenants for our properties. A significant economic downturn in one or both of these business segments could adversely affect our results of operations.

We face significant competition.

        Substantially all of our properties face competition for tenants. Some competing properties may be newer, better located or more attractive to tenants. Competing properties may have lower rates of occupancy than our properties, which may result in competing owners offering available space at lower rents than we offer at our properties. This competition may affect our ability to attract and retain tenants and may reduce the rents we are able to charge.

        In addition, we face significant competition for acquisition opportunities from other investors, including publicly traded and private REITs, numerous financial institutions, individuals and public and private companies. Because of competition, we may be unable to, or may pay a significantly increased purchase price to, acquire a desired property. Some of our competitors may have greater financial and management resources than we have.

When we renew leases or lease to new tenants our rents may decline and our expenses may increase and changes in tenants' requirements for leased space may adversely affect us.

        When we renew leases or lease to new tenants we may receive less rent than we currently receive. Market conditions may require us to lower our rents to retain tenants. When we lease to new tenants or renew leases we may have to spend substantial amounts for leasing commissions, tenant improvements or tenant inducements. Many of our leases are for properties that are specially suited to the particular business of our tenants. Because these properties have been designed or physically modified for a particular tenant, if the current lease is terminated or not renewed, we may be required to renovate the property at substantial costs, decrease the rent we charge or provide other concessions in order to lease the property to another tenant. In general, tenants have been increasingly seeking to increase their space utilization under their leases, including reducing the amount of square footage per employee at leased properties, which may reduce the demand for leased space. If a significant number of such events occur, our income and cash flow may materially decline and our ability to make regular distributions to our shareholders may be jeopardized.

Our failure or inability to meet certain terms of our revolving credit facility or term loan agreements would adversely affect our business and may prevent us from making distributions to our shareholders.

        Our revolving credit facility agreement includes various conditions to borrowings and our revolving credit facility and term loan agreements include various financial and other covenants, including covenants requiring us to maintain certain minimum debt service coverage and leverage ratios, and events of default. We may not be able to satisfy all of these conditions or may default on some of these covenants for various reasons, including matters which are beyond our control. If we are unable to borrow under our revolving credit facility, we may be unable to meet our business obligations or to grow by buying additional properties, or we may be required to sell some of our properties. If we default under our revolving credit facility or term loan agreement, the lenders may demand immediate

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payment and lenders under our revolving credit facility may elect not to make further borrowings available. Additionally, during the continuance of any event of default under our revolving credit facility or term loan agreement, we will be limited or in some cases prohibited from making distributions on our shares. Any default under our revolving credit facility or term loan agreements would likely have serious and adverse consequences to us and would likely cause the market price of our shares to materially decline.

        In the future, we may obtain additional debt financing, and the covenants and conditions which apply to any such additional indebtedness may be more restrictive than the covenants and conditions contained in our current revolving credit facility and term loan agreements.

Increasing interest rates may adversely affect us and the value of an investment in our shares.

        Interest rates have recently risen from their historical lows but remain below historical long term averages. Increasing interest rates may adversely affect us and the value of an investment in our shares, including in the following ways:

•

Amounts outstanding under our revolving credit facility agreement and term loan agreement and certain of our other debt bear interest at variable interest rates. When interest rates increase, so will our interest costs, which could adversely affect our cash flow, ability to pay principal and interest on debt, cost of refinancing debt when it becomes due and our ability to make or sustain distributions to our shareholders. Additionally, if we choose to hedge our interest rate risk, we cannot assure that the hedge will be effective or that our hedging counterparty will meet its obligations to us.



•

An increase in interest rates could decrease the amount buyers may be willing to pay for our properties, thereby reducing the market value of our properties and limiting our ability to sell properties or to obtain mortgage financing secured by our properties. Further, increased interest rates may effectively increase the cost of properties we acquire to the extent we utilize leverage for those acquisitions and may result in a reduction in our acquisitions to the extent we reduce the amount we offer to pay for properties, due to the effect of increased interest rates, to a price that sellers may not accept.



•

We expect to make regular distributions to our shareholders. When interest rates on debt investments available to investors rise, the market prices of distribution paying securities often decline. Accordingly, if interest rates rise, the market price of our shares may decline.

Our sales strategy may not be successful.

        An element of our business plan involves the sale of certain of our properties. We cannot assure that we will be able to find attractive sale opportunities or that any sale will be completed in a timely manner, if at all. Our ability to sell certain of our properties, and the prices we receive upon a sale, may be affected by many factors, and we may be unable to execute our sales strategy. In particular, these factors could arise from weakness in or the lack of an established market for a property, changes in the financial condition or prospects of prospective purchasers, the number of prospective purchasers, the number of competing properties on the market, a decline in current national or international economic conditions, and changes in laws, regulations or fiscal policies of jurisdictions in which the property is located. For these reasons, we may be unable to sell certain of our properties for an extended period of time or at all, and our business plan to sell certain of our properties may not succeed and we may incur expenses and reputational harm.

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Our acquisitions may not be successful.

        An element of our business plan involves the acquisition of additional properties. We cannot assure that we will be able to consummate attractive acquisition opportunities or that acquisitions we make will be successful.

        We might encounter unanticipated difficulties and expenditures relating to any acquired properties. Newly acquired properties might require significant management attention that would otherwise be devoted to our ongoing business. We might never realize the anticipated benefits of our acquisitions. Notwithstanding pre-acquisition due diligence, we do not believe that it is possible to fully understand a property before it is owned and operated for an extended period of time. For example, we could acquire a property that contains undisclosed defects in design or construction. In addition, after our acquisition of a property, the market in which the acquired property is located may experience unexpected changes that adversely affect the property's value. The occupancy of properties that we acquire may decline during our ownership, and rents that are in effect at the time a property is acquired may decline thereafter. Also, our property operating costs for acquisitions may be higher than we anticipate and acquisitions of properties may not yield the returns we expect and, if financed using debt or new equity issuances, may result in shareholder dilution. For these reasons, among others, our business plan to acquire additional properties may not succeed or may cause us losses.

Ownership of real estate is subject to environmental and climate change risks.

        Ownership of real estate is subject to risks associated with environmental hazards. We may be liable for environmental hazards at, or migrating from, our properties, including those created by prior owners or occupants, existing tenants, abutters or other persons. Various federal and state laws impose liabilities upon property owners, such as us, for any environmental damages arising at, or migrating from, properties they own, and we cannot assure that we will not be held liable for environmental investigation and clean up at, or near, our properties, including at sites we own and lease to our tenants. As an owner or previous owner of properties which contain environmental hazards, we also may be liable to governmental agencies or other parties for costs and damages they incur arising from environmental hazards at, or migrating from, our properties. Moreover, the costs and damages which may arise from environmental hazards are often difficult to project and may be substantial.

        Certain of our properties are used or have been used for industrial purposes. Though we have reviewed these and our other properties for potential environmental liabilities and have established a reserve for potential costs that may be incurred as a result of environmental contamination, we cannot assure that we have identified all potential environmental liabilities or that our reserve will be sufficient to cover any costs we may incur relating to environmental matters. Some of these properties contain, or may have contained, or are adjacent to or near other properties that contain, or may have contained, underground storage tanks for the storage of petroleum products and other hazardous or toxic substances. The presence of these tanks creates the potential for the release of petroleum products or other hazardous or toxic substances onto our properties. In addition, certain of our properties are on sites upon which or are adjacent to or near other properties upon which others, including former owners or tenants, have engaged, or may in the future engage, in activities that may release petroleum products or other hazardous or toxic substances.

        Except in limited instances, we do not have any insurance designated to limit any losses that we may incur as a result of known or unknown environmental conditions which are not caused by an insured event, such as, for example, fire or flood. We do not believe that there are environmental conditions at any of our properties that will materially and adversely affect us. However, we cannot assure that environmental conditions present at our properties or costs we may be required to incur in the future to address environmental contamination will not materially and adversely affect us.

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        We believe any asbestos in our buildings is contained in accordance with current regulations, and we have no current plans to remove any such asbestos. If we remove the asbestos or renovate or demolish these properties, certain environmental regulations govern the manner in which the asbestos must be handled and removed, and we could incur substantial costs complying with such regulations.

        The current political debate about climate change has resulted in various treaties, laws and regulations which are intended to limit carbon emissions. We believe these laws being enacted or proposed may cause energy costs at our properties to increase in the future. Laws enacted to mitigate climate change may make some of our buildings obsolete or cause us to make material investments in our properties which could materially and adversely affect our financial condition and results of operations. For more information regarding climate change matters and their possible adverse impact on us, please see "Management's Discussion and Analysis—Impact of Climate Change" in Part II, Item 7 of this Annual Report on Form 10-K.

Real estate ownership creates risks and liabilities.

        In addition to the risks related to environmental hazards and climate change, our business is subject to other risks associated with real estate ownership, including:

•

the illiquid nature of real estate markets, which limits our ability to sell our assets rapidly to respond to changing market conditions;



•

the subjectivity of real estate valuations and changes in such valuations over time;



•

property and casualty losses;



•

costs that may be incurred relating to property maintenance and repair, and the need to make expenditures due to changes in governmental regulations, including the Americans with Disabilities Act;



•

legislative and regulatory developments that may occur at the federal, state and local levels that have direct or indirect impact on the ownership, leasing and operation of our properties; and



•

litigation incidental to our business.

We have substantial debt obligations and may incur additional debt.

        As of December 31, 2013, we had $3.0 billion in debt outstanding, which was 47.4% of our total book capitalization. Our note indenture and revolving credit facility and term loan agreements permit us and our subsidiaries to incur additional debt, including secured debt. If we default in paying any of our debts or honoring our debt covenants, it may create one or more cross defaults, our debts may be accelerated and we could be forced to liquidate our assets for less than the values we would receive in a more orderly process.

We rely on information technology in our operations, and any material failure, inadequacy, interruption or security failure of that technology could harm our business.

        We rely on information technology networks and systems, including the Internet, to process, transmit and store electronic information and to manage or support a variety of our business processes, including financial transactions and maintenance of records, which may include personal identifying information of tenants and lease data. We rely on commercially available systems, software, tools and monitoring to provide security for processing, transmitting and storing confidential tenant information, such as individually identifiable information relating to financial accounts. Although we have taken steps to protect the security of the data maintained in our information systems, it is possible that our security measures will not be able to prevent the systems' improper functioning, or the improper disclosure of personally identifiable information such as in the event of cyber attacks. Security breaches,

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including physical or electronic break-ins, computer viruses, attacks by hackers and similar breaches, can create system disruptions, shutdowns or unauthorized disclosure of confidential information. Any failure to maintain proper function, security and availability of our information systems could interrupt our operations, damage our reputation, subject us to liability claims or regulatory penalties and could materially and adversely affect us.

Changes in lease accounting standards may materially and adversely affect us.

        The Financial Accounting Standards Board has proposed accounting rules that would require companies to capitalize all leases on their balance sheets by recognizing a lessee's rights and obligations. If such a proposal is adopted, many companies that account for certain leases on an "off balance sheet" basis would be required to account for such leases "on balance sheet." This change would remove many of the differences in the way companies account for owned property and leased property, and could have a material effect on various aspects of our tenants' businesses, including their credit quality and the factors they consider in deciding whether to own or lease properties. If the proposal is adopted, it could cause companies that lease properties to prefer shorter lease terms, in an effort to reduce the leasing liability required to be recorded on their balance sheets. The proposal could also make lease renewal options less attractive, as, under certain circumstances, the rule would require a tenant to assume that a renewal right will be exercised and accrue a liability relating to the longer lease term.

Risks Related to Our Securities

We cannot assure that we will continue to make distributions to our shareholders, and distributions we may make may include a return of capital.

        We intend to continue to make regular quarterly distributions to our shareholders. However:

•

our ability to make distributions will be adversely affected if any of the risks described herein, or other significant adverse events, occur;



•

our making of distributions is subject to compliance with restrictions contained in our revolving credit facility and term loan agreements and our debt indenture; and



•

any distributions will be made at the discretion of our Board of Trustees and will depend upon various factors that our Board of Trustees deems relevant, including, but not limited to, our results of operations, our financial condition, debt and equity capital available to us, our expectations of our future capital requirements and operating performance, including our funds from operations, or FFO, our normalized funds from operations, or Normalized FFO, and our cash available for distribution, restrictive covenants in our financial or other contractual arrangements (including those in our revolving credit facility and term loan agreements and senior notes indenture), tax law requirements to maintain our status as a REIT, restrictions under Maryland law and our expected needs and availability of cash to pay our obligations.

For these reasons, among others, our distribution rate may decline or we may cease making distributions. Also, our distributions may include a return of capital.

Any notes we may issue will be effectively subordinated to the debts of our subsidiaries and our secured debt.

        We conduct substantially all of our business through, and substantially all of our properties are owned by, our subsidiaries. Consequently, our ability to pay debt service on our outstanding notes and any notes we issue in the future will be dependent upon the cash flow of our subsidiaries and payments by those subsidiaries to us as dividends or otherwise. Our subsidiaries are separate legal entities and have their own liabilities. Payments due on our outstanding notes, and any notes we may issue, are, or

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will be, effectively subordinated to liabilities of our subsidiaries, including guaranty liabilities. Most of our subsidiaries have guaranteed our revolving credit facility and term loan but none of our subsidiaries guaranty our outstanding notes. In addition, as of December 31, 2013, our subsidiaries had $934.5 million of debt. Our outstanding notes are, and any notes we may issue will be, effectively subordinated to any secured debt with regard to our assets pledged to secure those debts.

Our notes may permit redemption before maturity, and our noteholders may be unable to reinvest proceeds at the same or a higher rate.

        The terms of our notes may permit us to redeem all or a portion of our outstanding notes after a certain amount of time, or up to a certain percentage of the notes prior to certain dates. Generally, the redemption price will equal the principal amount being redeemed, plus accrued interest to the redemption date, plus any applicable premium. If a redemption occurs, our noteholders may be unable to reinvest the money they receive in the redemption at a rate that is equal to or higher than the rate of return on the applicable notes.

There may be no public market for notes we may issue and one may not develop.

        Generally, any notes we may issue will be a new issue for which no trading market currently exists. We may not list our notes on any securities exchange or seek approval for price quotations to be made available through any automated quotation system. We cannot assure that an active trading market for any of our notes will exist in the future. Even if a market develops, the liquidity of the trading market for any of our notes and the market price quoted for any such notes may be adversely affected by changes in the overall market for fixed income securities, by changes in our financial performance or prospects, or by changes in the prospects for REITs or for the real estate industry generally.

Rating agency downgrades may increase our cost of capital.

        Our senior notes and our preferred shares are rated by two rating agencies. These rating agencies may elect to downgrade their ratings on our senior notes and our preferred shares at any time. Such downgrades may negatively affect our access to the capital markets and increase our cost of capital, including the interest rate and fees payable under our revolving credit facility and term loan agreements.

Conversion of our series D preferred shares or our series E preferred shares will dilute the ownership interests of existing shareholders.

        The conversion of some or all of our series D preferred shares or our series E preferred shares, including a conversion upon exercise of a "fundamental change" or "change of control," respectively, as such terms are defined in the applicable articles supplementary, will dilute the ownership interests of existing shareholders. Any sales in the public market of the common shares issuable upon such conversion could adversely affect prevailing market prices of our common shares. In addition, the existence of the series D preferred shares and the series E preferred shares may encourage short selling by market participants because the conversion of the series D preferred shares or the series E preferred shares could depress the price of our common shares or for other reasons.

Risks Related to Investing in Foreign Countries

We are subject to social, political and economic risks of doing business in other countries.

        We have conducted a portion of our business in Australia since our acquisition in October 2010 of CWH Australia Trust, an Australian listed property trust, and, as of December 31, 2013, we owned 11 properties (11 buildings) with approximately 1.8 million square feet in various locations in Australia. Circumstances and developments related to these international operations that could negatively affect

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our business, financial condition or results of operations include, but are not limited to, the following factors:

•

difficulties and costs of staffing and managing international operations;



•

currency restrictions, which may prevent the transfer of capital and profits to the United States;



•

unexpected changes in regulatory requirements;



•

potentially adverse tax consequences;



•

the impact of country-specific business cycles and economic instability; and



•

foreign ownership restrictions with respect to operations in countries.

        Although we have committed significant resources to manage our Australian business activities, if we are unable to successfully manage the risks associated with our foreign business, our non-U.S. investments could produce losses.

The depreciation in the value of the foreign currency in countries where we have a significant investment may adversely affect our results of operations and financial condition.

        We have pursued, and may continue to pursue, growth opportunities in Australia where the U.S. dollar is not the national currency. As of December 31, 2013, approximately 4.3% of our total assets were invested in Australian dollars, and we do not currently borrow in Australian dollars or enter currency derivative contracts to mitigate any foreign currency risk. As a result, we are subject to foreign currency risk due to potential fluctuations in exchange rates between the Australian and U.S. dollars. More specifically, a significant change in the value of the Australian dollar may have an adverse effect on our results of operations and financial condition. We may try to mitigate this foreign currency risk by borrowing under debt agreements denominated in Australian dollars and, on occasion and when deemed appropriate, using derivative contracts. However, we have no present intention to do so, and if we engage in such mitigation strategies, there can be no assurance that those attempts to mitigate foreign currency risk would be successful.

Risks Related to Our Relationship with RMR

We are dependent upon RMR to manage our business and execute our business plan.

        We have no employees. Personnel and services that we require are provided to us under contracts with RMR. Our ability to achieve our business objectives depends on RMR and its ability to manage our properties, to identify and complete our acquisitions and dispositions consistent with our business plan and to execute our financing strategy. Accordingly, our business is dependent upon RMR's business contacts, its ability to successfully hire, train, supervise and manage its personnel and its ability to maintain its operating systems. If we lose the services provided by RMR or its key personnel, our business and growth prospects may decline. We may be unable to duplicate the quality and depth of management available to us by becoming an internally managed company or by hiring another manager. Also, in the event RMR is unwilling or unable to continue to provide management services to us, our cost of obtaining substitute services may be greater than the fees we pay RMR under our management agreements, and as a result our expenses may increase.

Our management structure and agreements and relationships with RMR may restrict our investment activities and may create conflicts of interest or the perception of such conflicts.

        RMR is authorized to follow broad operating and investment guidelines and, therefore, has discretion in determining the types of properties that will be appropriate investments for us, as well as our individual operating and investment decisions. Our Board of Trustees periodically reviews our

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operating and investment guidelines and our operating activities and investments but it does not review or approve each decision made by RMR on our behalf. In addition, in conducting periodic reviews, our Board of Trustees relies primarily on information provided to it by RMR. RMR is beneficially owned by our Managing Trustees, Barry M. Portnoy and Adam D. Portnoy.

        In addition to managing CWH, RMR manages GOV, a publicly traded REIT that primarily owns buildings majority leased to government tenants throughout the United States, HPT, a publicly traded REIT that owns hotels and travel centers, SNH, a publicly traded REIT that primarily owns healthcare, senior living and medical office buildings, and SIR, a publicly traded REIT that is our former consolidated subsidiary and that primarily owns and invests in net leased, single tenant office and industrial properties throughout the United States and leased lands in Hawaii. RMR also provides services to other publicly and privately owned companies, including Five Star, which operates senior living communities; TA, which operates and franchises travel centers and convenience stores; and Sonesta, which operates, manages and franchises hotels, resorts and cruise ships. These multiple responsibilities to public companies and other businesses could create competition for the time and efforts of RMR and Messrs. Barry and Adam Portnoy. Also, RMR's multiple responsibilities to us and to other companies to which it provides management services may create potential conflicts of interest, or the appearance of such conflicts of interest.

        Our management agreements were negotiated between related parties, and the terms, including the fees payable to RMR, may not be as favorable to us as they would have been if they were negotiated between unrelated parties. In our management agreements with RMR, we acknowledge that RMR may engage in other activities or businesses and act as the manager to any other person or entity (including other REITs) even though such person or entity has investment policies and objectives similar to those of ours, and we are not entitled to preferential treatment in receiving information, recommendations and other services from RMR. Accordingly, we may lose investment opportunities to, and may compete for tenants with other businesses managed by RMR.

        Barry Portnoy is Chairman and an employee of RMR, and Adam Portnoy is President, Chief Executive Officer and a director of RMR. Adam Portnoy is also our President. Our Managing Trustees and two of our Independent Trustees are members of one or more boards of trustees or directors of other public companies to which RMR provides management services. All of our executive officers are also officers of RMR. The foregoing individuals may hold equity in or positions with other companies to which RMR provides management services. Such equity ownership and positions by our Trustees and officers could create, or appear to create, conflicts of interest with respect to matters involving us, RMR and its related parties.

Our management arrangements with RMR may discourage our change of control.

        A default under our revolving credit facility and term loan agreements would occur if RMR ceases to act as our business manager and property manager, unless waived by our lenders holding two-thirds of the aggregate credit exposure under the applicable agreement. RMR is able to terminate its management agreements with us if we experience a change of control. We may be unable to duplicate, without considerable cost increases, the quality and depth of management available to us by contracting with RMR if we become internally managed or if we contract with other parties for management services. For these reasons, our management agreements with RMR may discourage a change of control of us, including a change of control which might result in payment of a premium for our common shares.

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Provisions in our transaction agreements with other RMR managed entities or our management agreements with RMR may restrict our investment activities and create conflicts of interest or the perception of conflicts of interest.

        In our management agreements with RMR, we acknowledge that RMR may engage in other activities or businesses and act as the manager to any other person or entity (including other REITs) even though such person or entity has investment policies and objectives similar to those of ours and we are not entitled to preferential treatment in receiving information, recommendations and other services from RMR. Accordingly, we may lose investment opportunities to, and may compete for tenants with, other businesses managed by RMR. In addition, our transaction agreements with SNH and GOV also have restrictions on our right to make investments in properties that are within the investment focus of those other businesses. As a result of these contractual provisions, we have limited ability to invest in properties that are within the investment focus of certain other businesses managed by RMR. These agreements do not restrict our ability, or the ability of other businesses managed by RMR, to lease properties to any particular tenant.

The potential for conflicts of interest as a result of our management structure may provoke dissident shareholder activities that result in significant costs.

        In the past, in particular following periods of volatility in the overall market or declines in the market price of a company's securities, shareholder litigation, dissident shareholder trustee nominations and dissident shareholder proposals have often been instituted against companies alleging conflicts of interest in business dealings with affiliated and related persons and entities. Our relationships with RMR, SIR, GOV, SNH, Affiliates Insurance Company, or AIC, the other businesses and entities to which RMR provides management services, Messrs. Barry and Adam Portnoy and with other related parties of RMR may precipitate such activities. Related/Corvex have made conflicts of interest a theme of their campaign to remove all of our Trustees, without cause, and obtain control of the Company. Additionally, we are a party to numerous shareholder litigation, as noted below in Item 3 "Legal Proceedings", which may provoke further dissident shareholder activities. The Related/Corvex activities have resulted in, and future dissident shareholder activities may result in, substantial costs and a diversion of our management's attention even if the action is unfounded.

We may experience losses from our business dealings with AIC.

        We have invested approximately $5.2 million in AIC, we have purchased substantially all our property insurance in a program designed and reinsured in part by AIC, and we periodically consider the possibilities for expanding our relationship with AIC to other types of insurance. We, RMR and six other companies to which RMR provides management services each own 12.5% of AIC, and we and those other AIC shareholders participate in a combined insurance program designed and reinsured in part by AIC. Our principal reason for investing in AIC and for purchasing insurance in these programs is to seek to improve our financial results by obtaining improved insurance coverages at lower costs than may be otherwise available to us or by participating in any profits which we may realize as an owner of AIC. While we believe we have in the past benefitted from these arrangements, these beneficial financial results may not occur in the future, and we may need to invest additional capital in order to continue to pursue these results. AIC's business involves the risks typical of an insurance business, including the risk that it may not operate profitably. Accordingly, financial benefits from our business dealings with AIC may not be achieved in the future, and we may experience losses from these dealings.

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Risks Related to Our Organization and Structure

Ownership limitations and certain provisions in our declaration of trust, bylaws and shareholder rights agreement, as well as certain provisions of Maryland law, may deter, delay or prevent a change in our control or unsolicited acquisition proposals.

        Our declaration of trust or bylaws prohibit any shareholder other than RMR, its affiliates and certain persons who have been exempted by our Board of Trustees from owning (directly and by attribution) more than 9.8% of the number or value of shares of any class or series of our outstanding shares of beneficial interest, including our common shares. These provisions are intended to assist with our REIT compliance under the IRC and otherwise promote our orderly governance. However, these provisions also inhibit acquisitions of a significant stake in us and may deter, delay or prevent a change in our control or unsolicited acquisition proposals that a shareholder may consider favorable. Additionally, provisions contained in our declaration of trust and bylaws or under Maryland law may have a similar impact, including, for example, provisions relating to: the authority of our Board of Trustees, and not our shareholders, to adopt, amend and repeal our bylaws and to fill vacancies on our Board of Trustees; the fact that only our president, a majority of our Independent Trustees, our Board of Trustees or the holders of a majority of our common shares may call shareholder meetings; required qualifications for an individual to serve as a Trustee and a requirement that certain of our Trustees be "Managing Trustees" and other Trustees be "Independent Trustees", as defined in our governing documents; and the authority of our Board of Trustees to create and issue new classes or series of shares (including shares with voting rights and other rights and privileges that may deter a change in control) and issue additional common shares.

        We also currently maintain a shareholder rights agreement whereby, in the event a person or group of persons acquires 10% or more of our outstanding common shares, unless the acquisition is approved by our Board of Trustees, our shareholders, other than such person or group, will be entitled to purchase additional shares or other securities or property at a discount. In 2013, our Board of Trustees announced that it planned to accelerate the expiration date of this rights agreement after resolution of our disputes with Related/Corvex, which has not yet occurred. Until this agreement expires, it may deter, delay or prevent a change in our control or unsolicited acquisition proposals that a shareholder considers favorable.

        In addition, our shareholders agreement with respect to AIC provides that AIC and the other shareholders of AIC may have rights to acquire our interests in AIC in the event that anyone acquires more than 9.8% of our shares or we experience some other change in control.

Our ownership interest in AIC may prevent shareholders from accumulating large share ownership, from nominating or serving as Trustees, or from taking actions to otherwise control our business.

        As an owner of AIC, we are licensed and approved as an insurance holding company; and any shareholder who owns or controls 10% or more of our securities or anyone who wishes to solicit proxies for election of, or to serve as, one of our Trustees or for another proposal of business not approved by our Board of Trustees may be required to receive pre-clearance from the concerned insurance regulators. These pre-approval procedures may discourage or prevent investors from purchasing our securities, from nominating persons to serve as our Trustees or from taking other actions.

Our rights and the rights of our shareholders to take action against our Trustees and officers are limited.

        Our declaration of trust limits the liability of our Trustees and officers to us and our shareholders for money damages to the maximum extent permitted under Maryland law. Under current Maryland

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law, our Trustees and officers will not have any liability to us and our shareholders for money damages other than liability resulting from:

•

actual receipt of an improper benefit or profit in money, property or services; or



•

active and deliberate dishonesty by the Trustee or officer that was established by a final judgment as being material to the cause of action adjudicated.

        Our declaration of trust and indemnification agreements require us to indemnify any present or former Trustee or officer, to the maximum extent permitted by Maryland law, who is made or threatened to be made a party to a proceeding by reason of his or her service in that capacity. However, except with respect to proceedings to enforce rights to indemnification, we will indemnify any person referenced in the previous sentence in connection with a proceeding initiated by such person against us only if such proceeding is authorized by our declaration of trust or bylaws or by our Board of Trustees or shareholders. In addition, we may be obligated to pay or reimburse the expenses incurred by our present and former Trustees and officers without requiring a preliminary determination of their ultimate entitlement to indemnification. As a result, we and our shareholders may have more limited rights against our present and former Trustees and officers than might otherwise exist absent the provisions in our declaration of trust and indemnification agreements or that might exist with other companies, which could limit your recourse in the event of actions not in your best interest.

Disputes with SIR, GOV, SNH and RMR and shareholder litigation against us or our Trustees and officers may be referred to binding arbitration proceedings.

        Our contracts with SIR, GOV, SNH and RMR provide that any dispute arising under those contracts may be referred to binding arbitration proceedings. Similarly, our bylaws provide that actions by our shareholders against us or against our Trustees and officers, including derivative and class actions, may be referred to binding arbitration proceedings. As a result, we and our shareholders would not be able to pursue litigation for these disputes in courts against SIR, GOV, SNH, RMR or our Trustees and officers if the disputes were referred to arbitration. In addition, the ability to collect attorneys' fees or other damages may be limited in the arbitration proceedings, which may discourage attorneys from agreeing to represent parties wishing to commence such a proceeding.

We may change our operational, financing and investment policies without shareholder approval and we may become more highly leveraged, which may increase our risk of default under our debt obligations.

        Our Board of Trustees determines our operational, financing and investment policies and may amend or revise our policies, including our policies with respect to our intention to qualify for taxation as a REIT, acquisitions, dispositions, growth, operations, indebtedness, capitalization and distributions, or approve transactions that deviate from these policies, without a vote of, or notice to, our shareholders. Policy changes could adversely affect the market value of our common shares and our ability to make distributions to our shareholders. Further, our organizational documents do not limit the amount or percentage of indebtedness, funded or otherwise, that we may incur. Our Board of Trustees may alter or eliminate our current policy on borrowing at any time without shareholder approval. If this policy changed, we could become more highly leveraged, which could result in an increase in our debt service costs. Higher leverage also increases the risk of default on our obligations. In addition, a change in our investment policies, including the manner in which we allocate our resources across our portfolio or the types of assets in which we seek to invest, may increase our exposure to interest rate risk, real estate market fluctuations and liquidity risk.

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Risks Related to Our Taxation

The loss of our special tax statuses could have significant adverse consequences.

        As a REIT, we generally do not pay federal and state income taxes. However, actual qualification as a REIT under the IRC depends on satisfying complex statutory requirements, for which there are only limited judicial and administrative interpretations. We believe that we have been organized and have operated, and will continue to be organized and to operate, in a manner that qualified and will continue to qualify us to be taxed under the IRC as a REIT. However, we cannot be certain that, upon review or audit, the IRS will agree with this conclusion. Furthermore, there is no guarantee that the federal government will not someday eliminate REITs under the IRC.

        Maintaining our status as a REIT will require us to continue to satisfy certain tests concerning, among other things, the nature of our assets, the sources of our income and the amounts we distribute to our shareholders. In order to meet these requirements, it may be necessary for us to sell or forgo attractive investments.

        If we cease to be a REIT, then our ability to raise capital might be adversely affected, we will be in breach under our revolving credit facility and term loan agreements, we may be subject to material amounts of federal and state income taxes and the value of our shares likely would decline. In addition, if we lose or revoke our tax status as a REIT for a taxable year, we will generally be prevented from requalifying as a REIT for the next four taxable years.

        Similarly, our Australian operations benefit from locally available tax concessions which require us to satisfy complex requirements as to which there are only limited judicial and administrative interpretations. We believe that we have operated, and are operating, in compliance with the requirements for these Australian tax concessions. However, we cannot be certain that, upon review or audit, the local tax authority will agree. If we cease to be eligible for these Australian tax concessions, then we may be subject to material amounts of Australian income taxes and the value of our shares likely would decline; in addition, we could be precluded from requalifying for these Australian tax concessions again.

Distributions to shareholders generally will not qualify for reduced tax rates.

        Dividends payable by U.S. corporations to noncorporate shareholders, such as individuals, trusts and estates, are generally eligible for reduced tax rates. Distributions paid by REITs, however, generally are not eligible for these reduced rates. The more favorable rates for corporate dividends may cause investors to perceive that an investment in a REIT is less attractive than an investment in a non-REIT entity that pays dividends, thereby reducing the demand and market price of our shares.

REIT distribution requirements could adversely affect our ability to execute our business plan.

        We generally must distribute annually at least 90% of our taxable income, subject to certain adjustments and excluding any net capital gain, in order for federal corporate income tax not to apply to earnings that we distribute. To the extent that we satisfy this distribution requirement, but distribute less than 100% of our taxable income, we will be subject to federal corporate income tax on our undistributed taxable income. We intend to make distributions to our shareholders to comply with the REIT requirements of the IRC. In addition, we will be subject to a 4% nondeductible excise tax if the actual amount that we pay out to our shareholders in a calendar year is less than a minimum amount specified under federal tax laws.

        From time to time, we may generate taxable income greater than our income for financial reporting purposes prepared in accordance with U.S. generally accepted accounting principles, or GAAP, or differences in timing between the recognition of taxable income and the actual receipt of cash may occur. If we do not have other funds available in these situations we could be required to

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borrow funds on unfavorable terms, sell investments at disadvantageous prices or distribute amounts that would otherwise be invested in future acquisitions to make distributions sufficient to enable us to pay out enough of our taxable income to satisfy the REIT distribution requirement and to avoid corporate income tax and the 4% excise tax in a particular year. These alternatives could increase our costs or reduce our shareholders' equity. Thus, compliance with the REIT requirements may hinder our ability to grow, which could adversely affect the value of our shares.

Even if we qualify and remain qualified as a REIT, we may face other tax liabilities that reduce our cash flow.

        Even if we qualify and remain qualified for taxation as a REIT, we may be subject to certain federal, state and local taxes on our income and assets, including taxes on any undistributed income, excise taxes, state or local income, property and transfer taxes, such as mortgage recording taxes, and other taxes. See "Business—Federal Income Tax Considerations—Taxation as a REIT" in Part I, Item 1 of this Annual Report on Form 10-K. In addition, in order to meet the REIT qualification requirements, prevent the recognition of certain types of non-cash income, or avert the imposition of a 100% tax that applies to certain gains derived by a REIT from dealer property or inventory, we may hold some of our assets and operations through our taxable REIT subsidiaries or other subsidiary corporations that will be subject to corporate level income tax at regular rates. Any of these taxes would decrease cash available for distribution to our shareholders.

Item 1B.    Unresolved Staff Comments.

        None.

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Item 2.    Properties.

        General.    At December 31, 2013, we had real estate investments totaling approximately $5.5 billion in 125 properties (195 buildings), excluding properties classified as held for sale, that were leased to approximately 1,200 tenants. Our properties are located in both CBD areas and suburban areas. For further information by segment, see "Management's Discussion and Analysis of Financial Condition and Results of Operations" in Part II, Item 7 and Note 15 to the Notes to Consolidated Financial Statements in Part IV, Item 15 of this Annual Report on Form 10-K.

        The locations of our owned real estate at December 31, 2013, excluding properties classified as held for sale, were as follows (dollars in thousands):

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        At December 31, 2013, 13 properties (18 buildings) with an aggregate cost of $1.3 billion were encumbered by mortgage notes payable totaling $914.5 million (including net premiums and discounts). In addition, we had mortgage debt secured by two properties (three buildings) classified as held for sale totaling $20.0 million (including net premiums and discounts).

Item 3.    Legal Proceedings.

Young v. CommonWealth REIT

        On December 27, 2012, David Young filed a putative federal securities class action in the United States District Court for the District of Massachusetts, or the Massachusetts District Court, titled Young v. CommonWealth REIT, Case No. 1:12-cv-12405-DJC, or the Young Action. The Young Action is brought on behalf of purchasers of our common shares between January 10, 2012 and August 8, 2012, and alleges securities fraud claims against CWH and certain of our officers under Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder. The complaint alleges generally that CWH violated the federal securities laws by making false and misleading representations about our business, operations and management. The plaintiff seeks compensatory damages plus counsel fees and expenses. On January 22, 2013, CWH moved to dismiss the Young Action on the grounds that the claims asserted (1) are subject to binding arbitration under our bylaws, and (2) fail to state a claim for relief under Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5. We have also filed a demand for arbitration with the American Arbitration Association, or AAA. On February 25, 2013, Mr. Young filed a motion to appoint him as lead plaintiff and his counsel as lead counsel, which the Massachusetts District Court granted on May 20, 2013, all in accordance with customary procedures for purported class action litigation. On July 22, 2013, Mr. Young filed an amended complaint. On September 20, 2013, we filed an opening brief in support of our motion to dismiss, and the parties completed briefing on the motion on December 3, 2013. We believe that the Young Action is without merit, and intend to defend against all claims asserted.

Corvex Management LP v. CommonWealth REIT

        On February 27, 2013, Related/Corvex filed a complaint in the Circuit Court for Baltimore City, State of Maryland, or the Maryland Court, titled Corvex Management LP v. CommonWealth REIT, Case No. 24-C-13-001111, or the Related/Corvex Maryland Action, against CWH, our Board of Trustees and RMR. The complaint generally alleged breaches of fiduciary duties, conflicts of interest, corporate waste and breach of contract. Related/Corvex sought declaratory and injunctive relief, rescission and damages, including counsel fees and expenses.

        On the same day, we filed a demand for arbitration with the AAA on behalf of CWH and the individual defendants, with the exception of RMR, pursuant to our position that the claims in the Related/Corvex Maryland Action were subject to arbitration. On March 5, 2013, we amended our demand for arbitration to add Related Fund Management, LLC as a respondent. On March 12, 2013, RMR separately filed a demand for arbitration with the AAA, pursuant to RMR's position that the claims in the Related/Corvex Maryland Action were subject to arbitration.

        On March 13, 2013, Related/Corvex filed a Petition to Stay Arbitration in the Related/Corvex Maryland Action. On March 15, 2013, Related/Corvex filed an amended complaint and a partial motion for summary judgment asking the Maryland Court to invalidate certain provisions of our bylaws regarding nomination and removal of Trustees as inconsistent with our declaration of trust. On April 1, 2013, Related/Corvex voluntarily dismissed their claims against RMR in the Related/Corvex Maryland

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Action without prejudice. On May 8, 2013, the Maryland Court denied the Related/Corvex Petition to Stay Arbitration and ordered the parties to arbitrate the claims in this dispute. In the same opinion, the Maryland Court denied the partial motion for summary judgment as moot. On June 6, 2013, Related/Corvex filed a notice of their intent to appeal the Maryland Court's May 8 rulings, and, on June 21, 2013, Related/Corvex voluntarily dismissed their appeal. The parties agreed to consolidate this arbitration with RMR's pending arbitration arising from this action, as well as the pending arbitration in the Related/Corvex Massachusetts Action, which is discussed below, or together, the Related/Corvex Arbitration.

        On May 30, 2013, Related/Corvex filed their statement of counterclaims, or the Counterclaims, which generally alleged that certain of our bylaws were invalid, and also alleged breaches of fiduciary duty, entrenchment, conflicts of interest and corporate waste. The Counterclaims sought declaratory and injunctive relief, including a declaration that our entire Board of Trustees may be removed without cause, and damages, including counsel fees and expenses. On June 10, 2013, Related/Corvex filed a motion for partial summary judgment, challenging the validity of certain provisions of our bylaws and further challenging the effect of our Board of Trustees' decision to opt into certain provisions of the Maryland Unsolicited Takeovers Act on the ability of our shareholders to remove all of our Trustees without cause and in one removal action.

        On June 17, 2013, we and our Board of Trustees each filed an amended statement of claims and answer to Related/Corvex's Counterclaims, seeking a declaration that the record date bylaws were valid and that Related/Corvex's purported consent solicitation was false and misleading for, among other reasons, their failure to disclose the true purpose of the consent solicitation, as well as material arrangements, agreements and understandings, as required by applicable law. On July 11, 2013, Related/Corvex filed a supporting motion for an order directing our officers to call a special meeting of shareholders to elect successor Trustees, and a hearing on both motions was held on July 26, 2013. By order dated August 7, 2013, the three-person arbitration panel, or the Arbitration Panel, denied summary judgment on Related/Corvex's claims that their consent solicitation was proper. The Arbitration Panel also invalidated our bylaw providing that one or more shareholders requesting a record date for a consent solicitation to remove Trustees must have held at least three percent (3%) of our common shares for at least three years, but found that the previous Company bylaw requiring that a shareholder requesting a record date for a consent solicitation meet a $2,000 share ownership threshold for a period of at least one year remained in effect. The Arbitration Panel further found that Related/Corvex's motion for an order directing our officers to convene a special meeting was premature.

        On September 19, 2013, the Arbitration Panel dismissed with prejudice as to Related/Corvex Count VIII of Related/Corvex's Counterclaims, which alleged derivative claims for breach of fiduciary duty and sought, among other things, money damages. On October 6, 2013, RMR and Related/Corvex entered into a stipulation dismissing with prejudice all claims previously asserted by Related/Corvex against RMR, and on October 7, 2013, the Arbitration Panel issued an order granting the parties' stipulation and proposed order. An evidentiary hearing on all remaining matters in dispute was held from October 7, 2013 through October 17, 2013, and the parties submitted post-hearing briefs on October 30, 2013.

        On November 18, 2013, the Arbitration Panel issued findings on the parties' remaining claims, or the Panel Findings, finding, among other things, that Related/Corvex's purported consent solicitation to remove the Board of Trustees, without cause, was not properly conducted and could not be validated. The Arbitration Panel provided for a limited opportunity for Related/Corvex to conduct a new consent solicitation pursuant to a timeline established by the Arbitration Panel as follows: (1) Related/Corvex were required to give notice to the Arbitration Panel on or before November 28, 2013 if they wished to move forward with a new solicitation; (2) Related/Corvex are required to submit a record date request to the Board of Trustees on or before February 16, 2014; (3) a record date would be established within

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ten (10) business days after the request; and (4) the new consent solicitation must be concluded within thirty (30) days of the record date. The Arbitration Panel also ruled that, in the event Related/Corvex were to pursue a new consent solicitation, and succeed in removing all of the Trustees, our officers must promptly call a special meeting for the election of successor Trustees, and that only shareholders who have held 1%, or $2,000 in market value, of our shares continuously for one year may submit nominations for successor Trustees to be elected at that special meeting. The Panel Findings stated that our election to opt into Section 3-803 of the Maryland Unsolicited Takeovers Act does not prevent removal of the Trustees without cause. The Arbitration Panel upheld the provision in our bylaws requiring that only a shareholder who has held 1%, or $2,000 in market value, of our common shares continuously for one year may request a record date to act by written consent, but ruled that such shareholder need not hold certificates for all shares of beneficial interest owned by such shareholder. The Arbitration Panel further ruled that our bylaws establishing a thirty (30) day period for the Board of Trustees to respond to a valid record date request, a sixty (60) day period for the Board of Trustees to set a record date after receipt of a valid request and a ninety (90) day period to review and certify the results of a consent solicitation were invalid. Finally, the Arbitration Panel rejected certain claims for indemnification asserted both by us and Related/Corvex in connection with the litigation and arbitration proceedings, and ruled that Section 7.12 of our Declaration of Trust and Section 15.2 of our bylaws were invalid because they contravened Section 8.3 of our Declaration of Trust. On November 25, 2013, Related/Corvex notified the Arbitration Panel that they desire to pursue a new consent solicitation, and on February 14, 2014, Related/Corvex submitted a request for a record date. Our Board of Trustees has set February 18, 2014 as the record date for shareholders entitled to execute or revoke consents in the new consent solicitation, and the consent solicitation period ends on March 20, 2014.

Delaware County Employees Retirement Fund v. Portnoy I

        On February 28, 2013, Delaware County Employees Retirement Fund, or Del-Co, a purported CWH shareholder, filed a complaint in the Massachusetts District Court, titled Delaware County Employees Retirement Fund v. Portnoy, Case No. 1:13-cv-10405-DJC, or the First Del-Co Action. The First Del-Co Action purports to bring claims individually and derivatively on behalf of the nominal defendant, CWH, against RMR and certain current and former officers and/or members of our Board of Trustees. The complaint in the First Del-Co Action asserts claims against the defendants for breach of fiduciary duty, aiding and abetting breach of fiduciary duty, breach of contract, gross mismanagement, waste of corporate assets and abuse of control. The Del-Co plaintiffs seek declaratory and injunctive relief, as well as compensatory and rescissory damages, including counsel fees and expenses.

        On March 1, 2013, Del-Co filed a motion requesting that the Massachusetts District Court, among other things, issue a temporary restraining order, or TRO, enjoining CWH and our Board of Trustees from consummating our then pending equity offering and debt tender offer. After a joint hearing was held before the court on the motions for a TRO filed in this action and in the Related/Corvex Massachusetts Action, which is discussed below, on March 4, 2013, the Massachusetts District Court issued an order denying both motions for a TRO. Among other reasons for denying both motions, the Massachusetts District Court found that Del-Co and Related/Corvex failed to meet their burden of showing there was a likelihood that the claims asserted by them regarding the equity offering and, with respect to the First Del-Co Action, the debt tender offer, would succeed on the merits. The equity offering closed the following morning, March 5, 2013.

        On March 4, 2013, we filed a demand for arbitration with the AAA on behalf of CWH and the individual defendants, with the exception of RMR, pursuant to our position that the claims in the First Del-Co Action are subject to arbitration. On April 8, 2013, RMR was added as a co-claimant in the Del-Co arbitration. Pursuant to a stipulated order, as amended from time to time, the parties have

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completed briefing on the Del-Co plaintiffs' petition to stay arbitration and have subsequently submitted additional supplemental authority to the court. On November 20, 2013, the Massachusetts District Court held a hearing on the Del-Co plaintiffs' petition to stay arbitration. We believe that the First Del-Co Action is without merit, and intend to defend against all claims asserted.

Delaware County Employees Retirement Fund v. Portnoy II

        On January 24, 2014, Del-Co and Edmund Sweeney filed a second complaint in the Massachusetts District Court, titled Delaware County Employees Retirement Fund v. Portnoy, Case No. 1:14-cv-10186-DJC, or the Second Del-Co Action. The Second Del-Co Action purports to bring claims derivatively on behalf of the nominal defendant, CWH, against RMR and certain current and former officers and/or members of the Board of Trustees. The complaint in the Second Del-Co Action asserts claims against the defendants for breach of fiduciary duty in connection with advancement and indemnification of legal expenses incurred by certain current and former Trustees and officers of CWH in connection with the Related/Corvex actions, as well as claims for breach of fiduciary duty in connection with the failure to purchase director and officer liability insurance. The plaintiffs seek monetary and injunctive relief, including an injunction permanently enjoining defendants from being indemnified or advanced any fees and expenses incurred in the Related/Corvex Arbitration. On February 24, 2014, the parties filed a proposed stipulated order requesting that the Massachusetts District Court stay the Second Del-Co Action pending the court's ruling on arbitrability in the First Del-Co Action. We believe that the Second Del-Co Action is without merit, and intend to defend against all claims asserted.

Corvex Management LP v. CommonWealth REIT

        On March 1, 2013, Related/Corvex filed a complaint in the Massachusetts District Court, titled Corvex Management LP v. CommonWealth REIT, Case No. 1:13-cv-10475-DJC, or the Related/Corvex Massachusetts Action, against CWH and our Board of Trustees. The Related/Corvex Massachusetts Action alleged securities fraud claims under Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder. Related/Corvex sought injunctive and declaratory relief, including a declaration that our arbitration bylaw is unenforceable. Also on March 1, 2013, Related/Corvex filed a motion requesting that the court, among other things, issue a TRO enjoining us and our Board of Trustees from consummating the March 2013 equity offering. As mentioned above, the court denied that motion on March 4, 2013.

        On March 4, 2013, we filed a demand for arbitration with the AAA on behalf of CWH and the individual defendants pursuant to our position that the claims in the Related/Corvex Massachusetts Action are subject to arbitration. Pursuant to the parties' agreement to consolidate this arbitration with the concurrently pending arbitration of Related/Corvex's Maryland state law claims, Related/Corvex voluntarily dismissed this action on June 5, 2013. On June 17, 2013, we and our Board of Trustees each filed a separate request with the Arbitration Panel seeking an entry of award in our and their favor, and against Related/Corvex, for all claims previously asserted by Related/Corvex in this action. As explained above, on November 18, 2013, the Arbitration Panel issued the Panel Findings ruling on the parties' remaining claims.

William Gore v. Portnoy

        On February 4, 2013, William Gore, a purported CWH shareholder, filed a complaint in the Circuit Court for Montgomery County, State of Maryland, titled William Gore v. Portnoy, Case No. 373086-V, or the Gore Action. The Gore Action purports to bring claims individually and derivatively on behalf of the nominal defendant, CWH, against our current and former Trustees, certain of our officers and CWH, as nominal defendant. The complaint alleges claims of breach of fiduciary duty, waste of corporate assets and unjust enrichment. The complaint seeks injunctive and declaratory relief, restitution and damages, including counsel fees and expenses.

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        On March 7, 2013, we filed a demand for arbitration with the AAA for the Gore Action, pursuant to our position that the claims in this action are subject to arbitration. On March 21, 2013, the parties each selected an arbitrator in this matter. On May 20, 2013, the CWH Trustees filed a petition for order to arbitrate and for a stay of proceedings pursuant to the Maryland Uniform Arbitration Act. On June 21, 2013, Mr. Gore filed his response to the CWH Trustees' petition for order to arbitrate, as well as a separate petition to stay arbitration, and the parties completed briefing on both petitions on August 2, 2013. On December 2, 2013, the parties filed a joint status report requesting that the court continue to stay proceedings in both the Gore Action and the related arbitration until March 3, 2014, which the court granted on December 3, 2013. We believe that the Gore Action is without merit, and intend to defend against all claims asserted.

Katz v. CommonWealth REIT

        On March 7, 2013, Jason Matthew Katz, a purported CWH shareholder, filed a complaint in the Maryland Court, titled Katz v. CommonWealth REIT, Case No. 24-C-13-001299, or the Katz Action. The Katz Action purports to bring claims individually and on behalf of all others similarly situated against CWH and our current and former Trustees. The complaint alleges claims of breach of fiduciary duty. The complaint seeks injunctive and declaratory relief, rescission of the March 2013 equity offering, restitution and damages, including counsel fees, expenses and, if applicable, pre-judgment and post-judgment interest.

        On April 1, 2013, we filed a demand for arbitration with the AAA for the Katz Action, pursuant to our position that the claims in this action are subject to arbitration. Pursuant to the court's scheduling order, as amended from time to time, the plaintiff filed a petition to stay arbitration on April 19, 2013, and the parties completed briefing on the petition on September 16, 2013. On January 21, 2014, the court granted the parties' joint stipulation and motion to consolidate the Katz Action with the Central Laborers Action, discussed below. On February 19, 2014, the Maryland Court denied the pending petition to stay arbitration and ordered the parties to arbitrate the claims in this dispute. We believe that the Katz Action is without merit, and intend to defend against all claims asserted.

Central Laborers' Pension Fund v. Portnoy

        On April 5, 2013, the Central Laborers' Pension Fund, or Central Laborers, a purported CWH shareholder, filed a complaint in the Maryland Court, titled Central Laborers' Pension Fund v. Portnoy, Case No. 24-C-13-001966, or the Central Laborers Action. The Central Laborers Action purports to bring claims individually, on behalf of all others similarly situated, and on behalf of CWH against CWH and our Board of Trustees. The complaint alleges, among other things, claims for breaches of fiduciary duties, unjust enrichment and waste of corporate assets. The complaint seeks declaratory and injunctive relief, restitution and damages, including counsel fees and expenses. On April 17, 2013, Central Laborers filed an amended complaint, adding plaintiff William McGinley, a purported CWH shareholder, and requesting a declaration that CWH's shareholders may remove Trustees without cause.

        Pursuant to our position that the claims in this action are subject to arbitration, we filed a demand for arbitration with the AAA on April 25, 2013. We and our Trustees filed motions for an order to arbitrate and for a stay of proceedings pursuant to the Maryland Uniform Arbitration Act on May 8, 2013 and May 16, 2013, respectively. On May 22, 2013, the court issued an order staying all proceedings in the litigation pending the court's ruling on the pending petitions for an order to arbitrate. On May 31, 2013, Central Laborers and Mr. McGinley filed a second amended complaint, adding plaintiff Howard Ginsberg, a purported CWH shareholder.

        Pursuant to the court's scheduling order, the parties completed briefing on June 17, 2013. On January 21, 2014, the court granted the parties' joint stipulation and motion to consolidate the Central

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Laborers Action with the Katz Action, discussed above. On February 19, 2014, the Maryland Court granted the pending petitions for order to arbitrate and ordered the parties to arbitrate the claims in this dispute. We believe that the Central Laborers Action is without merit, and intend to defend against all claims asserted.

Chashin v. Reit Management & Research LLC

        On October 3, 2013, A. Bruce Chashin, a purported CWH shareholder, filed a complaint in the Massachusetts District Court, titled Chashin v. Reit Management & Research LLC, Case No. 1:13-cv-12472-DJC, or the Chashin Action. The Chashin Action purports to bring claims derivatively on behalf of CWH against CWH, current and former members of our Board of Trustees, certain of our officers and our manager, RMR. Among other things, the complaint challenges the arbitration clauses contained in our bylaws and our management agreements with RMR. The complaint also asserts, among other things, claims for breaches of fiduciary duties, waste of corporate assets and abuse of a position of control. The complaint seeks declaratory and injunctive relief, restitution and damages, including the imposition of a constructive trust and fees and expenses. On November 4, 2013, the defendants filed a demand for arbitration with the AAA. Pursuant to an agreement of the parties, the arbitration has been stayed until March 21, 2014. On January 21, 2014, the court extended the time to answer or otherwise respond to the complaint to March 21, 2014, the date agreed upon by the parties. We believe that the Chashin Action is without merit, and intend to defend against all claims asserted.

Item 4.    Mine Safety Disclosures.

        Not applicable.

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PART II

Item 5.    Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

        Our common shares are traded on the NYSE (symbol: CWH). The following table sets forth for the periods indicated the high and low sale prices for our common shares as reported in the NYSE Composite Transactions reports:

        The closing price of our common shares on the NYSE on February 27, 2014, was $26.61 per share.

        As of February 27, 2014, there were 2,077 shareholders of record of our common shares.

        In October 2012, we declared a new quarterly common share dividend rate of $0.25 per share ($1.00 per share per year). Information about distributions declared to common shareholders is summarized in the table below. Common share distributions are generally declared and paid in the quarter following the quarter to which they relate.

        All common share distributions shown in the table above have been paid in cash. We currently intend to continue to declare and pay common share distributions on a quarterly basis in cash. However, the timing and amount of future distributions is determined at the discretion of our Board of Trustees and will depend upon various factors that our Board of Trustees deems relevant, including, but not limited to, our results of operations, our financial condition, debt and equity capital available to us, our expectations of our future capital requirements and operating performance, including our FFO, our Normalized FFO, and our cash available for distribution, restrictive covenants in our financial or other contractual arrangements (including those in our revolving credit facility and term loan agreements and senior notes indenture), tax law requirements to qualify for taxation as and remain a REIT, restrictions under Maryland law and our expected needs and availability of cash to pay our obligations. Therefore, there can be no assurance that we will continue to pay distributions in the future or that the amount of any distributions we do pay will not decrease.

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Item 6.    Selected Financial Data.

        The following table sets forth selected financial data for the periods and dates indicated. This data should be read in conjunction with, and is qualified in its entirety by reference to, "Management's Discussion and Analysis of Financial Condition and Results of Operations" in Part II, Item 7 and the consolidated financial statements and accompanying notes included in "Exhibits and Financial Statement Schedules" in Part IV, Item 15 of this Annual Report on Form 10-K. Reclassifications have been made to the prior years' financial statements to conform to the current year's presentation. Amounts are in thousands, except per share data.

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Item 7.    Management's Discussion and Analysis of Financial Condition and Results of Operations.

        The following discussion should be read in conjunction with our consolidated financial statements and accompanying notes included elsewhere in this Annual Report on Form 10-K.

OVERVIEW

        We primarily own office buildings in CBD and suburban locations throughout the United States, consisting of 114 properties (184 buildings) with a combined 35.5 million square feet (excluding properties classified as held for sale). We also own 1.8 million square feet of space in 11 properties (11 buildings) located in Australia and 22,000,000 common shares, or approximately 44.2%, of SIR, a REIT that primarily owns and invests in net leased, single tenant office and industrial properties throughout the United States and leased lands in Hawaii.

        SIR was a 100% owned subsidiary of ours until March 12, 2012, on which date SIR completed the SIR IPO and became a publicly owned company with shares listed on the NYSE. After the SIR IPO, and until July 2, 2013, SIR was one of our consolidated subsidiaries and we consolidated SIR's financial position and results of operations in our financial statements.

        On July 2, 2013, SIR issued and sold to the public 10,500,000 of its common shares. Prior to the completion of this offering, our 22,000,000 common shares of SIR represented approximately 56.0% of SIR's outstanding common shares, and SIR was one of our consolidated subsidiaries. Following the completion of this offering, our 22,000,000 common shares of SIR represented approximately 44.2% of SIR's outstanding common shares, and SIR ceased to be our consolidated subsidiary. As a result of this offering, our investment in SIR was reduced below 50%; consequently, effective July 2, 2013, we no longer consolidate SIR but instead account for such investment using the equity method. Under the equity method, we record our percentage share of net earnings of SIR in our consolidated statements of operations.

        Until March 15, 2013, we also owned 9,950,000 common shares of GOV. We used the equity method to account for our ownership of GOV. GOV, a REIT that primarily owns properties located throughout the United States that are majority leased to government tenants, was our wholly owned subsidiary until its initial public offering in June 2009, or the GOV IPO, when it became a publicly owned company with shares listed on the NYSE. On March 15, 2013, we sold all 9,950,000 common shares that we owned of GOV in a public offering for net proceeds of $239.6 million (after deducting underwriters' discounts and commissions and expenses). We recognized a gain on the sale of this equity investment of $66.3 million as a result of the per share sales price of this transaction being above our per share carrying value. We had previously recognized gains totaling approximately $53.2 million on subsequent sales by GOV of its common shares, which reduced our percentage ownership of GOV from approximately 49.9% at the time of the GOV IPO, until March 15, 2013 when we sold our remaining common shares of GOV.

        See Note 12 to our Notes to Consolidated Financial Statements in Part IV, Item 15 of this Annual Report on Form 10-K for further information regarding our agreements with SIR and GOV.

        Since Related/Corvex publicly announced on February 26, 2013 that they had accumulated common shares of the Company, they have undertaken a series of actions in an effort to influence and control us, including publishing "open" letters to our Board of Trustees, announcing conditional, unfinanced purported offers to acquire all the Company's common shares, running a consent solicitation seeking to remove, without cause, all of the members of our Board of Trustees which the Arbitration Panel determined "was not properly conducted and cannot be validated" and pursuing legal proceedings against the Company, the Board of Trustees and RMR. The Arbitration Panel also

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provided for an opportunity for Related/Corvex to conduct a new consent solicitation within a limited time period. Related/Corvex have filed a definitive solicitation statement with the SEC for (i) a new consent solicitation for their proposal to remove, without cause, all of the members of our Board of Trustees, including the two recently added Independent Trustees, and (ii) in the event this removal proposal is successful, the solicitation of proxies for the election of seven nominees for new trustees proposed by Related/Corvex at a special meeting of shareholders which would be required for the election of replacement trustees. We have filed a definitive consent revocation statement in opposition to the Related/Corvex removal proposal. Our Board of Trustees has set a record date of February 18, 2014 for purposes of determining shareholders entitled to execute or revoke consents to the Related/Corvex removal proposal and, under the rules established by the Arbitration Panel, the Related/Corvex consent solicitation must be concluded within 30 days of the record date, or March 20, 2014. The Arbitration Panel also ruled that, in the event the Related/Corvex consent solicitation succeeds in removing all of our Trustees, our officers must promptly call a special meeting of shareholders for the election of successor trustees, and that only shareholders who have held 1%, or $2,000 in market value, of our common shares continuously for one year may submit nominations for successor trustees to be elected at that special meeting.

        If our entire Board of Trustees is removed as a result of the Related/Corvex consent solicitation, that action may, among other things, disrupt our business and operations and affect our ability to pay dividends, repurchase shares, borrow money and implement our business plan. For a further discussion of the legal proceedings described above, please see the section captioned "Legal Proceedings" in Part I, Item 3 of this Annual Report on Form 10-K; and for a further discussion of the risks related to the Related/Corvex activities, please see the section captioned "Risk Factors" in Part I, Item 1A of this Annual Report on Form 10-K.

Property Operations

        As of December 31, 2013, 89.6% of our total square feet was leased, compared to 92.0% leased as of December 31, 2012. These results reflect the reduction in occupancy related to the deconsolidation of SIR as of July 2, 2013 and the 0.3 percentage point decrease in occupancy at properties we owned continuously since January 1, 2012, offset by higher occupancy levels at properties acquired since January 1, 2012. Occupancy data for 2013 and 2012 is as follows (square feet in thousands):

        As of December 31, 2013, we had three CBD properties (four buildings) and 42 suburban properties (106 buildings) with a combined 8,425,548 square feet classified as held for sale. Results of operations for properties sold or held for sale as of December 31, 2013 are included in discontinued operations in our consolidated statements of operations. These properties and their operating results

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are excluded from the data in the preceding paragraph and, except as noted, from the balance of this Management's Discussion and Analysis of Financial Condition and Results of Operations.

        The average effective rental rate per square foot, as defined below, for our properties for the years ended December 31, 2013 and 2012 are as follows:

        During the year ended December 31, 2013, we renewed leases for 3,795,000 square feet and entered into new leases for 1,357,000 square feet, at weighted average cash rental rates that were approximately 0.1% below cash rental rates previously charged for the same space. The weighted average lease term based on square feet for leases entered into during the year ended December 31, 2013 was 7.3 years. Commitments for tenant improvements, leasing commissions, tenant concessions, including free rent and tenant reimbursements, for leases entered into during the year ended December 31, 2013 totaled $128.5 million, or $24.94 per square foot on average (approximately $3.42 per square foot per year of the lease term).

        Leasing market conditions in the majority of our markets appear to be stabilizing but remain weak. Required tenant concessions, including tenant improvements, leasing brokerage commissions, tenant reimbursements and free rent, have increased in certain markets since 2008 and we believe they generally may continue to increase during the coming year. Tenant concessions are generally amortized during the terms of the affected leases. We believe that present real estate leasing market conditions in the majority of areas where our properties are located may result in stable or slowly and modestly improving occupancies and effective rents, or gross rents less amortization of landlord funded tenant improvements and leasing costs, during 2014. However, there are too many variables for us to reasonably project with any assurance what the financial impact of changing market conditions will have on our occupancy, rental income or financial results for future periods.

        We review all of our long lived assets for possible impairments following the end of each quarter and when there is an event or change in circumstances that indicates an impairment in value may have occurred. We determined the net carrying value of 36 properties (76 buildings) sold during the year ended December 31, 2013 and 39 properties (93 buildings) that were classified as held for sale as of December 31, 2013 exceeded their estimated fair values based on third party broker information, independent appraisals and sales comparables, current sales prices and purchase offers, resulting in impairment charges aggregating $227.1 million.

        As of December 31, 2013, approximately 6.5% of our leased square feet and 5.8% of our annualized rental revenue, determined as set forth below, are included in leases scheduled to expire through December 31, 2014. Renewed and new leases and rental rates at which available space may be relet in the future will depend on prevailing market conditions at the times these leases are negotiated.

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Lease expirations by year, as of December 31, 2013, are as follows (square feet and dollars in thousands):

        RMR employs a tenant review process for us. RMR assesses tenants on an individual basis and does not employ a uniform set of credit criteria. In general, depending on facts and circumstances, RMR evaluates the creditworthiness of a tenant based on information concerning the tenant that is provided by the tenant and, in some cases, information that is publicly available or obtained from third party sources. RMR also often uses a third party service to monitor the credit ratings of debt securities of our existing tenants whose debt securities are rated by a nationally recognized statistical rating organization. No material changes in portfolio wide tenant credit quality have occurred since December 31, 2012.

        A principal source of funds for our operations is rents from tenants at our properties. Rents are generally received from our tenants monthly in advance, except from our government tenants, who

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usually pay rents monthly in arrears. As of December 31, 2013, tenants responsible for 1% or more of our total annualized rental revenue were as follows (square feet in thousands):