PS BUSINESS PARKS, INC./MD - Annual Report: 2011 (Form 10-K)

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UNITED STATES SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

     For the fiscal year ended December 31, 2011.

or

     For the transition period from                 to                 

Commission File Number 1-10709

PS BUSINESS PARKS, INC.

(Exact name of registrant as specified in its charter)

701 Western Avenue, Glendale, California 91201-2397

(Address of principal executive offices) (Zip Code)

818-244-8080

(Registrant’s telephone number, including area code)

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

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

None

(Title of class)

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

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

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  þ    No  ¨

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  þ    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§232.405) is not contained herein, and will not be contained, to the best of the 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.     þ

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  ¨    No  þ

As of June 30, 2011, the aggregate market value of the registrant’s common stock held by non-affiliates of the registrant was $1,026,372,826 based on the closing price as reported on that date.

Number of shares of the registrant’s common stock, par value $0.01 per share, outstanding as of February 20, 2012 (the latest practicable date): 24,129,684.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the definitive proxy statement to be filed in connection with the Annual Meeting of Shareholders to be held in 2012 are incorporated by reference into Part III of this Annual Report on Form 10-K.

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PART I

ITEM 1. BUSINESS

Forward-Looking Statements

Forward-looking statements are made throughout this Annual Report on Form 10-K. For this purpose, any statements contained herein that are not statements of historical fact may be deemed to be forward-looking statements. Without limiting the foregoing, the words “may,” “believes,” “anticipates,” “plans,” “expects,” “seeks,” “estimates,” “intends,” and similar expressions are intended to identify forward-looking statements. There are a number of important factors that could cause the results of the Company to differ materially from those indicated by such forward-looking statements, including but not limited to: (a) changes in general economic and business conditions; (b) decreases in rental rates or increases in vacancy rates/failure to renew or replace expiring leases; (c) tenant defaults; (d) the effect of the recent credit and financial market conditions; (e) our failure to maintain our status as a REIT; (f) the economic health of our tenants; (g) increases in operating costs; (h) casualties to our properties not covered by insurance; (i) the availability and cost of capital; (j) increases in interest rates and its effect on our stock price; (k) other factors discussed under the heading “Item 1A. Risk Factors”. In light of the significant uncertainties inherent in the forward-looking statements included herein, the inclusion of such information should not be regarded as a representation by us or any other person that our objectives and plans will be achieved. Moreover, we assume no obligation to update these forward-looking statements to reflect actual results, changes in assumptions or changes in other factors affecting such forward-looking statements, except as required by law.

The Company

PS Business Parks, Inc. (“PSB”) is a fully-integrated, self-advised and self-managed real estate investment trust (“REIT”) that owns, operates acquires, and develops commercial properties, primarily multi-tenant flex, office and industrial space. PS Business Parks, L.P. (the “Operating Partnership”) is a California limited partnership, which owns directly or indirectly substantially all of our assets and through which we conduct substantially all of our business. PSB is the sole general partner of the Operating Partnership and, as of December 31, 2011, owned 76.8% of the common partnership units. The remaining common partnership units are owned by Public Storage (“PS”). PSB, as the sole general partner of the Operating Partnership, has full, exclusive and complete responsibility and discretion in managing and controlling the Operating Partnership. Unless otherwise indicated or unless the context requires otherwise, all references to “the Company,” “we,” “us,” “our,” and similar references mean PS Business Parks, Inc. and its subsidiaries, including the Operating Partnership.

As of December 31, 2011, the Company owned and operated 27.2 million rentable square feet of commercial space, comprising 102 business parks, located in eight states: Arizona, California, Florida, Maryland, Oregon, Texas, Virginia and Washington. The Company focuses on owning concentrated business parks as these parks provide the Company with the greatest flexibility to meet its customer needs. The Company also manages 1.3 million rentable square feet on behalf of PS.

History of the Company: The Company was formed in 1990 as a California corporation under the name Public Storage Properties XI, Inc. In a March 17, 1998 merger with American Office Park Properties, Inc. (“AOPP”) (the “Merger”), the Company acquired the commercial property business previously operated by AOPP and was renamed “PS Business Parks, Inc.” Prior to the Merger in January, 1997, AOPP was reorganized to succeed to the commercial property business of PS, becoming a fully integrated, self-advised and self-managed REIT.

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In 2011 and 2010, the Company acquired 7.9 million square feet for an aggregate purchase price of $855.2 million. The table below reflects the assets acquired during the years ended December 31, 2011 and 2010 (in thousands):

In August, 2011, the Company completed the sale of Westchase Corporate Park, a 177,000 square foot flex park consisting of 13 buildings in Houston, Texas, for a gross sales price of $9.8 million, resulting in a net gain of $2.7 million.

In addition to the 2010 acquisitions, during 2010, the Company completed construction of a new building within its Miami International Commerce Center (“MICC”) in Miami, Florida, which added 75,000 square feet of rentable small tenant industrial space. In January, 2010, the Company completed the sale of a 131,000 square foot office building located in Houston, Texas. The gross sales price was $10.0 million, resulting in a net gain of $5.2 million.

In 2009, the Company sold 3.4 acres of land held for development in Portland, Oregon, for a gross sales price of $2.7 million, resulting in a net gain of $1.5 million. The Company made no acquisitions during the years ended December 31, 2009 and 2008.

In 2007, the Company acquired three business parks comprising 870,000 square feet for an aggregate cost of $140.6 million in Redmond, Washington, Santa Clara, California and Fairfax, Virginia.

From 1998 through 2006, the Company acquired 14.9 million square feet of commercial space, developed an additional 500,000 square feet and sold 1.9 million square feet along with some parcels of land.

The Company has elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended (the “Code”), commencing with its taxable year ended December 31, 1990. To the extent that the Company continues to qualify as a REIT, it will not be taxed, with certain limited exceptions, on the net income that is currently distributed to its shareholders.

The Company’s principal executive offices are located at 701 Western Avenue, Glendale, California 91201-2397. The Company’s telephone number is (818) 244-8080. The Company maintains a website with the address www.psbusinessparks.com. The information contained on the Company’s website is not a part of, or incorporated by reference into, this Annual Report on Form 10-K. The Company makes available free of charge through its website its Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, and amendments to these reports, as soon as reasonably practicable after the Company electronically files such material with, or furnishes such material to, the Securities and Exchange Commission.

Business of the Company: The Company is in the commercial property business, with 102 business parks consisting of multi-tenant flex, industrial and office space. The Company owns 14.7 million square feet of flex space. The Company defines “flex” space as buildings that are configured with a combination of warehouse and office space and can be designed to fit a wide variety of uses. The warehouse component of the flex space has a number of uses including light manufacturing and assembly, storage and warehousing, showroom, laboratory, distribution and research and development activities. The office component of flex space is complementary to the

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warehouse component by enabling businesses to accommodate management and production staff in the same facility. The Company owns 7.5 million square feet of industrial space that has characteristics similar to the warehouse component of the flex space as well as ample dock space. In addition, the Company owns 5.0 million square feet of low-rise office space, generally either in business parks that combine office and flex space or in submarkets where the economics of the market demand an office build-out.

The Company’s commercial properties typically consist of business parks with low-rise buildings, ranging from one to 48 buildings per park, located on parcels of various sizes and comprising from approximately 12,000 to 3.3 million aggregate square feet of rentable space. Facilities are managed through either on-site management or offices central to the facilities. Parking is generally open but in some instances is covered. The ratio of parking spaces to rentable square feet ranges from two to six per thousand square feet depending upon the use of the property and its location. Office space generally requires a greater parking ratio than most industrial uses. The Company may acquire properties that do not have these characteristics.

The tenant base for the Company’s facilities is diverse. The portfolio can be bifurcated into those facilities that service small to medium-sized businesses and those that service larger businesses. Approximately 34.9% of in-place rents from the portfolio are derived from facilities that serve small to medium-sized businesses. A property in this facility type is typically divided into units ranging in size from 500 to 4,999 square feet and leases generally range from one to three years. The remaining 65.1% of in-place rents from the portfolio are derived from facilities that serve larger businesses, with units greater than or equal to 5,000 square feet. The Company also has several tenants that lease space in multiple buildings and locations. The U.S. Government is the largest tenant with multiple leases encompassing approximately 829,000 square feet or 6.5% of the Company’s annualized rental income.

The Company currently owns properties in eight states and it may expand its operations to other states or reduce the number of states in which it operates. Properties are acquired for both income and potential capital appreciation; there is no limitation on the amount that can be invested in any specific property. Although there are no restrictions on our ability to expand our operations into foreign markets, we currently operate solely within the United States and have no foreign operations.

The Company owns land which may be used for the development of commercial properties. The Company owns approximately 6.4 acres of land in Northern Virginia, 11.5 acres in Portland, Oregon and 10.0 acres in Dallas, Texas as of December 31, 2011.

Operating Partnership

The properties in which the Company has an equity interest generally are owned by the Operating Partnership. Through this organizational structure, the Company has the ability to acquire interests in additional properties in transactions that could defer the contributors’ tax consequences by causing the Operating Partnership to issue equity interests in return for interests in properties.

The Company is the sole general partner of the Operating Partnership. As of December 31, 2011, the Company owned 76.8% of the common partnership units of the Operating Partnership, and the remainder of such common partnership units were owned by PS. The common units owned by PS may be redeemed by PS from time to time, subject to the provisions of our charter, for cash or, at our option, shares of our common stock on a one-for-one basis. Also as of December 31, 2011, in connection with the Company’s issuance of publicly traded Cumulative Preferred Stock, the Company owned 23.9 million preferred units of the Operating Partnership of various series with an aggregate redemption value of $598.5 million with terms substantially identical to the terms of the publicly traded depositary shares each representing 1/1,000 of a share of 6.700% to 7.375% Cumulative Preferred Stock of the Company. In addition, as of December 31, 2011, the Operating Partnership had outstanding 223,300 units of its 7.125% Series N preferred partnership units that are owned by third parties with an aggregate redemption value of $5.6 million. The Operating Partnership has the right to redeem each series of preferred units held by these third parties on or after the fifth anniversary of the issuance date of the series at the original capital contribution plus the cumulative priority return, as defined, to the redemption date to the extent not previously distributed. Each series of preferred units is exchangeable for shares of a corresponding series of the Company’s Cumulative Redeemable Preferred Stock on or after the tenth anniversary of the date of

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issuance at the option of the Operating Partnership or a majority of the holders of the applicable series of preferred units.

As the general partner of the Operating Partnership, the Company has the exclusive responsibility under the Operating Partnership Agreement to manage and conduct the business of the Operating Partnership. The Board of Directors directs the affairs of the Operating Partnership by managing the Company’s affairs. The Operating Partnership will be responsible for, and pay when due, its share of all administrative and operating expenses of the properties it owns.

The Company’s interest in the Operating Partnership entitles it to share in cash distributions from, and the profits and losses of, the Operating Partnership in proportion to the Company’s economic interest in the Operating Partnership (apart from tax allocations of profits and losses to take into account pre-contribution property appreciation or depreciation). The Company since 1998 has paid per share dividends on its common and preferred stock that track, on a one-for-one basis, the amount of per unit cash distributions the Company receives from the Operating Partnership in respect of the common and preferred partnership units in the Operating Partnership that are owned by the Company.

Cost Allocation and Administrative Services

Pursuant to a cost sharing and administrative services agreement, the Company shares costs with PS for certain administrative services. These services include investor relations, legal, corporate tax and information systems. Under this agreement, costs are allocated to the Company in accordance with its proportionate share of these costs. These allocated costs totaled $442,000, $543,000 and $372,000 for the years ended December 31, 2011, 2010 and 2009, respectively.

Common Officers and Directors with PS

Ronald L. Havner, Jr., Chairman of the Company, is also the Chairman of the Board, Chief Executive Officer and President of PS. Gary E. Pruitt, an independent director of the Company is also a trustee of PS. The Company engages additional executive personnel who render services exclusively for the Company. However, it is expected that certain officers of PS will continue to render services for the Company as requested pursuant to the cost sharing and administrative services agreement.

Property Management

The Company manages commercial properties owned by PS, which are generally adjacent to self-storage facilities, for a fee of 5% of the gross revenues of such properties in addition to reimbursement of direct costs. The property management contract with PS is for a seven-year term with the agreement automatically extending for an additional one-year period upon each one-year anniversary of its commencement (unless cancelled by either party). Either party can give notice of its intent to cancel the agreement upon expiration of its current term. Management fee revenue derived from this management contract with PS totaled $684,000, $672,000 and $698,000 for the years ended December 31, 2011, 2010 and 2009, respectively.

PS also provides property management services for the self-storage component of two assets owned by the Company. These self-storage facilities, located in Palm Beach County, Florida, operate under the “Public Storage” name. Either the Company or PS can cancel the property management contract upon 60 days notice. Management fee expenses under the contract were $52,000, $48,000 and $50,000 for the years ended December 31, 2011, 2010 and 2009, respectively.

Management

Joseph D. Russell, Jr. leads the Company’s senior management team. Mr. Russell is President and Chief Executive Officer of the Company. The Company’s senior management includes: John W. Petersen, Executive Vice President and Chief Operating Officer; Edward A. Stokx, Executive Vice President and Chief Financial Officer; Maria R. Hawthorne, Executive Vice President, East Coast; Trenton A. Groves, Vice President and Corporate Controller; Mike Van Etten, Vice President of Construction Management; Coby A. Holley,

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Vice President (Pacific Northwest Division); Robin E. Mather, Vice President (Southern California Division); William A. McFaul, Vice President (Washington Metro Division); Ross K. Parkin, Vice President, Acquisitions and Dispositions; Eddie F. Ruiz, Vice President and Director of Facilities; Viola I. Sanchez, Vice President (Southeast Division); and David A. Vicars, Vice President (Midwest Division).

REIT Structure

If certain detailed conditions imposed by the Code and the related Treasury Regulations are met, an entity, such as the Company, that invests principally in real estate and that otherwise would be taxed as a corporation may elect to be treated as a REIT. The most important consequence to the Company of being treated as a REIT for federal income tax purposes is that the Company can deduct dividend distributions (including distributions on preferred stock) to its shareholders, thus effectively eliminating the “double taxation” (at the corporate and shareholder levels) that typically results when a corporation earns income and distributes that income to shareholders in the form of dividends.

The Company believes that it has operated, and intends to continue to operate, in such a manner as to qualify as a REIT under the Code, but no assurance can be given that it will at all times so qualify. To the extent that the Company continues to qualify as a REIT, it will not be taxed, with certain limited exceptions, on the taxable income that is distributed to its shareholders.

Operating Strategy

The Company believes its operating, acquisition and finance strategies combined with its diversified portfolio produces a low risk, stable growth business model. The Company’s primary objective is to grow shareholder value. Key elements of the Company’s growth strategy include:

Maximize Net Cash Flow of Existing Properties: The Company seeks to maximize the net cash flow generated by its properties by (i) maximizing average occupancy rates, (ii) achieving the highest possible levels of realized monthly rents per occupied square foot and (iii) controlling its operating cost structure by improving operating efficiencies and economies of scale. The Company believes that its experienced property management personnel and comprehensive systems combined with increasing economies of scale will enhance the Company’s ability to meet these goals. The Company seeks to increase occupancy rates and realized monthly rents per square foot by providing its field personnel with incentives to lease space to higher credit tenants and to maximize the return on investment in each lease transaction. The Company seeks to maximize its cash flow by controlling capital expenditures associated with re-leasing space by acquiring and owning properties with easily reconfigured space that appeal to a wide range of tenants.

Focus on Targeted Markets: The Company intends to continue investing in markets that have characteristics which enable them to be competitive economically. The Company believes that markets with some combination of above average population growth, job growth, education levels and personal income will produce better overall economic returns. The Company targets individual properties in those markets that are close to critical infrastructure, middle to high income housing, universities and have easy access to major transportation arteries.

Reduce Capital Expenditures and Increase Occupancy Rates by Providing Flexible Properties and Attracting a Diversified Tenant Base: By focusing on properties with easily reconfigurable space, the Company believes it can offer facilities that appeal to a wide range of potential tenants, which aids in reducing the capital expenditures associated with re-leasing space. The Company believes this property flexibility also allows it to better serve existing tenants by accommodating their expansion and contraction needs. In addition, the Company believes that a diversified tenant base and property flexibility helps it maintain occupancy rates during periods when market demand is weak, by enabling it to attract a greater number of potential users to its space.

Provide Superior Property Management: The Company seeks to provide a superior level of service to its tenants in order to achieve high occupancy and rental rates, as well as minimal customer turnover. The Company’s property management offices are primarily located on-site or regionally located, providing tenants with convenient access to management and helping the Company maintain its properties and convey a sense of quality, order and security. The Company has significant experience in acquiring properties managed by others

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and thereafter improving tenant satisfaction, occupancy levels, renewal rates and rental income by implementing established tenant service programs.

Financing Strategy

The Company’s primary objective in its financing strategy is to maintain financial flexibility and a low risk capital structure. Key elements of this strategy are:

Retain Operating Cash Flow: The Company seeks to retain significant funds (after funding its distributions and capital improvements) for additional investments. During the years ended December 31, 2011 and 2010, the Company distributed 37.4% and 45.2%, respectively, of its funds from operations (“FFO”) to common shareholders/unit holders. FFO is computed in accordance with the White Paper on FFO approved by the Board of Governors of the National Association of Real Estate Investment Trusts (“NAREIT”). The White Paper defines FFO as net income, computed in accordance with U.S. generally accepted accounting principles (“GAAP”), before depreciation, amortization, gains or losses on asset dispositions, net income allocable to noncontrolling interests — common units, net income allocable to restricted stock unit holders and nonrecurring items. FFO is a non-GAAP financial measure and should be analyzed in conjunction with net income. However, FFO should not be viewed as a substitute for net income as a measure of operating performance as it does not reflect depreciation and amortization costs or the level of capital expenditure and leasing costs necessary to maintain the operating performance of the Company’s properties, which are significant economic costs and could materially impact the Company’s results of operations. Other REITs may use different methods for calculating FFO and, accordingly, the Company’s FFO may not be comparable to other real estate companies’ funds from operations. See Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources — Non-GAAP Supplemental Disclosure Measure: Funds from Operations,” for a reconciliation of FFO and net income allocable to common shareholders and for information on why the Company presents FFO.

Perpetual Preferred Stock/Units: The primary source of leverage in the Company’s capital structure is perpetual preferred stock or equivalent preferred units in the Operating Partnership. This method of financing eliminates interest rate and refinancing risks because the dividend rate is fixed and the stated value or capital contribution is not required to be repaid. In addition, the consequences of defaulting on required preferred distributions is less severe than with debt. The preferred shareholders may elect two additional directors if six quarterly distributions go unpaid, whether or not consecutive.

Debt Financing: The Company, from time to time, has used debt financing to facilitate acquisitions. The primary source of debt the Company has historically relied upon to provide short-term capital is its $250.0 million unsecured line of credit (the “Credit Facility”). In addition, during 2011, in connection with its $520.0 million portfolio acquisition in Northern California, the Company obtained a $250.0 million unsecured three-year term loan and assumed a $250.0 million mortgage note.

Access to Capital: The Company targets a minimum ratio of FFO to combined fixed charges and preferred distributions paid of 3.0 to 1.0. Fixed charges include interest expense. Preferred distributions include amounts paid to preferred shareholders and preferred Operating Partnership unit holders. For the year ended December 31, 2011, the FFO to combined fixed charges and preferred distributions paid ratio was 4.0 to 1.0, excluding the issuance costs related to the redemption of preferred equity. The Company believes that its financial position will enable it to access capital to finance its future growth. Subject to market conditions, the Company may add leverage to its capital structure. Throughout this Form 10-K, we use the term “preferred equity” to mean both the preferred stock issued by the Company (including the depositary shares representing interests in that preferred stock) and the preferred partnership units issued by the Operating Partnership and the term “preferred distributions” to mean dividends and distributions on the preferred stock and preferred partnership units.

Competition

Competition in the market areas in which many of the Company’s properties are located is significant and has from time to time reduced the occupancy levels and rental rates of, and increased the operating expenses of, certain of these properties. Competition may be accelerated by any increase in availability of funds for

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investment in real estate. Barriers to entry are relatively low for those with the necessary capital and the Company competes for property acquisitions and tenants with entities that have greater financial resources than the Company. Sublease space and unleased developments are expected to continue to provide competition among operators in certain market areas in which the Company operates. While the Company will have to respond to market demands, management believes that the combination of its ability to offer a variety of options within its business parks and the Company’s financial stability provides it with an opportunity to compete favorably in its markets.

The Company’s properties compete for tenants with similar properties located in its markets primarily on the basis of location, rent charged, services provided and the design and condition of improvements. The Company believes it possesses several distinguishing characteristics that enable it to compete effectively in the flex, office and industrial space markets. The Company believes its personnel are among the most experienced in these real estate markets. The Company’s facilities are part of a comprehensive system encompassing standardized procedures and integrated reporting and information networks. The Company believes that the significant operating and financial experience of its executive officers and directors combined with the Company’s capital structure, national investment scope, geographic diversity and economies of scale should enable the Company to compete effectively.

Investments in Real Estate Facilities

As of December 31, 2011, the Company owned and operated 27.2 million rentable square feet comprised of 102 business parks in eight states compared to 21.8 million rentable square feet at December 31, 2010.

Summary of Business Model

The Company has a diversified portfolio. It is diversified geographically in eight states and has a diversified customer mix by size and industry concentration. The Company believes that this diversification combined with a conservative financing strategy, focus on markets with strong demographics for growth and our operating strategy gives the Company a business model that mitigates risk and provides strong long-term growth opportunities.

Restrictions on Transactions with Affiliates

The Company’s Bylaws provide that the Company may engage in transactions with affiliates provided that a purchase or sale transaction with an affiliate is (i) approved by a majority of the Company’s independent directors and (ii) fair to the Company based on an independent appraisal or fairness opinion.

Borrowings

As of December 31, 2011, the Company had outstanding mortgage notes payable of $282.1 million compared to $51.5 million at December 31, 2010. The increase in outstanding mortgage notes payable was due to the assumption of a $250.0 million mortgage note related to the Northern California Portfolio acquisition in December, 2011. See Notes 5 and 6 to the consolidated financial statements for a summary of the Company’s outstanding borrowings as of December 31, 2011.

On August 3, 2011, the Company modified the terms of its Credit Facility with Wells Fargo Bank. The modification of the Credit Facility increased the borrowing limit to $250.0 million and extended the expiration to August 1, 2015. The modified rate of interest charged on borrowings is equal to a rate ranging from the London Interbank Offered Rate (“LIBOR”) plus 1.00% to LIBOR plus 1.85% depending on the Company’s credit ratings. Currently, the Company’s rate under the Credit Facility is LIBOR plus 1.10%. In addition, the Company is required to pay an annual facility fee ranging from 0.15% to 0.45% of the borrowing limit depending on the Company’s credit ratings (currently 0.15%). As of December 31, 2011, the Company had $185.0 million outstanding on the Credit Facility at an interest rate of 1.41%. Subsequent to December 31, 2011, the Company repaid $85.0 million on the Credit Facility reducing the outstanding balance to $100.0 million as of February 24, 2012. The Company had $93.0 million outstanding on the Credit Facility at an interest rate of 2.11% at December 31, 2010. The Company had $1.1 million and $356,000 of unamortized commitment fees as of

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December 31, 2011 and 2010, respectively. The Credit Facility requires the Company to meet certain covenants, with which the Company was in compliance at December 31, 2011 and 2010. Interest on outstanding borrowings is payable monthly.

As described in Note 3, in connection with the Northern California Portfolio acquisition, the Company entered into a term loan on December 20, 2011 with Wells Fargo Bank, National Association, as Administrative Agent and the lenders named therein (the “Term Loan”). Pursuant to the Term Loan, the Company borrowed $250.0 million for a three year term through December 20, 2014. However, the maturity date of the Term Loan Agreement can be extended by one year at the Company’s election. Interest on the amounts borrowed under the Term Loan will accrue based on an applicable rate ranging from LIBOR plus 1.15% to LIBOR plus 2.25% depending on the Company’s credit ratings. Currently, the Company’s rate under the Term Loan is LIBOR plus 1.20% (1.50% at December 31, 2011). The Company had $729,000 of unamortized commitment fees as of December 31, 2011. The covenants and events of default contained in the Credit Facility are incorporated into the Term Loan by reference, and the Term Loan is cross-defaulted to the Credit Facility. The Term Loan can be repaid in full or part prior to its maturity without penalty.

On February 9, 2011, the Company entered into an agreement with PS to borrow $121.0 million with a maturity date of August 9, 2011 at an interest rate of LIBOR plus 0.85%. The Company repaid, in full, the note payable to PS upon maturity.

The Company has broad powers to borrow in furtherance of the Company’s objectives. The Company has incurred in the past, and may incur in the future, both short-term and long-term indebtedness to increase its funds available for investment in real estate, capital expenditures and distributions.

Employees

As of December 31, 2011, the Company employed 145 individuals, primarily personnel engaged in property operations.

Insurance

The Company believes that its properties are adequately insured. Facilities operated by the Company have historically been covered by comprehensive insurance, including fire, earthquake, liability and extended coverage from nationally recognized carriers.

Environmental Matters

Compliance with laws and regulations relating to the protection of the environment, including those regarding the discharge of material into the environment, has not had any material effect upon the capital expenditures, earnings or competitive position of the Company.

Substantially all of the Company’s properties have been subjected to Phase I environmental reviews. Such reviews have not revealed, nor is management aware of, any probable or reasonably possible environmental costs that management believes would have a material adverse effect on the Company’s business, assets or results of operations, nor is the Company aware of any potentially material environmental liability.

ITEM 1A. RISK FACTORS

In addition to the other information in our Annual Report on Form 10-K, you should consider the risks described below that we believe may be material to investors in evaluating the Company. This section contains forward-looking statements, and in considering these statements, you should refer to the qualifications and limitations on our forward-looking statements that are described in Item 1, “Business — Forward-Looking Statements.”

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Since our business consists primarily of acquiring and operating real estate, we are subject to the risks related to the ownership and operation of real estate that can adversely impact our business and financial condition.

The value of our investments may be reduced by general risks of real estate ownership: Since we derive substantially all of our income from real estate operations, we are subject to the general risks of acquiring and owning real estate-related assets, including:

Certain significant costs, such as mortgage payments, real estate taxes, insurance and maintenance, generally are not reduced even when a property’s rental income is reduced. In addition, environmental and tax laws, interest rate levels, the availability of financing and other factors may affect real estate values and property income. Furthermore, the supply of commercial space fluctuates with market conditions.

If our properties do not generate sufficient income to meet operating expenses, including any debt service, tenant improvements, lease commissions and other capital expenditures, we may have to borrow additional amounts to cover fixed costs, and we may have to reduce our distributions to shareholders.

There is significant competition among commercial properties: Many other commercial properties compete with our properties for tenants. Some of the competing properties may be newer and better located than our properties. Competition in the market areas in which many of our properties are located is significant and has affected our occupancy levels, rental rates and operating expenses. We also expect that new properties will be built in our markets. In addition, we compete with other buyers, many of which are larger than us, for attractive commercial properties. Therefore, we may not be able to grow as rapidly as we would like.

We may encounter significant delays and expense in re-letting vacant space, or we may not be able to re-let space at existing rates, in each case resulting in losses of income: When leases expire, we will incur expenses in retrofitting space and we may not be able to re-lease the space on the same terms. Certain leases provide tenants with the right to terminate early if they pay a fee. As of December 31, 2011, our properties generally had lower vacancy rates than the average for the markets in which they are located, and leases accounting for 23.2% of our annualized rental income are scheduled to expire in 2012. While we have estimated our cost of renewing leases

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that expire in 2012, our estimates could be wrong. If we are unable to re-lease space promptly, if the terms are significantly less favorable than anticipated or if the costs are higher, we may have to reduce our distributions to shareholders.

Tenant defaults and bankruptcies may reduce our cash flow and distributions: We may have difficulty collecting from tenants in default, particularly if they declare bankruptcy. This could affect our cash flow and our ability to fund distributions to shareholders. Since many of our tenants are non-rated private companies, this risk may be enhanced. There is inherent uncertainty in a tenant’s ability to continue paying rent if they are in bankruptcy.

We may be adversely affected if casualties to our properties are not covered by insurance: We could suffer uninsured losses or losses in excess of our insurance policy limits for occurrences such as earthquakes or hurricanes that adversely affect us or even result in loss of the property. Approximately 41.0% of our properties are located in California and are generally in areas that are subject to risks of earthquake related damage. We might still remain liable on any mortgage debt or other unsatisfied obligations related to that property.

The illiquidity of our real estate investments may prevent us from adjusting our portfolio to respond to market changes: There may be delays and difficulties in selling real estate. Therefore, we cannot easily change our portfolio when economic conditions change. Also, tax laws limit a REIT’s ability to sell properties held for less than four years.

We may be adversely affected by changes in laws: Increases in income and service taxes may reduce our cash flow and ability to make expected distributions to our shareholders. Our properties are also subject to various federal, state and local regulatory requirements, such as state and local fire and safety codes. If we fail to comply with these requirements, governmental authorities could fine us or courts could award damages against us. We believe our properties comply with all significant legal requirements. However, these requirements could change in a way that would reduce our cash flow and ability to make distributions to shareholders.

We may incur significant environmental remediation costs: As an owner and operator of real properties, under various federal, state and local environmental laws, we are required to clean up spills or other releases of hazardous or toxic substances on or from our properties. Certain environmental laws impose liability whether or not the owner knew of, or was responsible for, the presence of the hazardous or toxic substances. In some cases, liability may not be limited to the value of the property. The presence of these substances, or the failure to properly remediate any resulting contamination, whether from environmental or microbial issues, also may adversely affect our ability to sell, lease, operate, or encumber our facilities for purposes of borrowing.

We have conducted preliminary environmental assessments of most of our properties (and conduct these assessments in connection with property acquisitions) to evaluate the environmental condition of, and potential environmental liabilities associated with, our properties. These assessments generally consist of an investigation of environmental conditions at the property (not including soil or groundwater sampling or analysis), as well as a review of available information regarding the site and publicly available data regarding conditions at other sites in the vicinity. In connection with these property assessments, our operations and recent property acquisitions, we have become aware that prior operations or activities at some properties or from nearby locations have or may have resulted in contamination to the soil or groundwater at these properties. In circumstances where our environmental assessments disclose potential or actual contamination, we may attempt to obtain indemnifications and, in appropriate circumstances, we obtain limited environmental insurance in connection with the properties acquired, but we cannot assure you that such protections will be sufficient to cover actual future liabilities nor that our assessments have identified all such risks. Although we cannot provide any assurance, based on the preliminary environmental assessments, we are not aware of any environmental contamination of our facilities material to our overall business, financial condition or results of operations.

There has been an increasing number of claims and litigation against owners and managers of rental properties relating to moisture infiltration, which can result in mold or other property damage. When we receive a complaint concerning moisture infiltration, condensation or mold problems and/or become aware that an air quality concern exists, we implement corrective measures in accordance with guidelines and protocols we have developed with the assistance of outside experts. We seek to work proactively with our tenants to resolve

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moisture infiltration and mold-related issues, subject to our contractual limitations on liability for such claims. However, we can give no assurance that material legal claims relating to moisture infiltration and the presence of, or exposure to, mold will not arise in the future.

Property taxes can increase and cause a decline in yields on investments: Each of our properties is subject to real property taxes, which could increase in the future as property tax rates change and as our properties are assessed or reassessed by tax authorities. Recent local government shortfalls in tax revenue may cause pressure to increase tax rates or assessment levels or impose new taxes. Such increases could adversely impact our profitability.

We must comply with the Americans with Disabilities Act and fire and safety regulations, which can require significant expenditures: All our properties must comply with the Americans with Disabilities Act and with related regulations (the “ADA”). The ADA has separate compliance requirements for “public accommodations” and “commercial facilities,” but generally requires that buildings be made accessible to persons with disabilities. Various state laws impose similar requirements. A failure to comply with the ADA or similar state laws could lead to government imposed fines on us and/or litigation, which could also involve an award of damages to individuals affected by the non-compliance. In addition, we must operate our properties in compliance with numerous local fire and safety regulations, building codes, and other land use regulations. Compliance with these requirements can require us to spend substantial amounts of money, which would reduce cash otherwise available for distribution to shareholders. Failure to comply with these requirements could also affect the marketability of our real estate facilities.

We incur liability from tenant and employment-related claims: From time to time we have to make monetary settlements or defend actions or arbitration to resolve tenant or employment-related claims and disputes.

Global economic conditions adversely affect our business, financial condition, growth and access to capital.

There continues to be global economic uncertainty, elevated levels of unemployment, reduced levels of economic activity, and it is uncertain as to when economic conditions will improve. These negative economic conditions in the markets where we operate facilities, and other events or factors that adversely affect demand for commercial real estate, could continue to adversely affect our business. To the extent that turmoil in the financial markets returns or intensifies, it has the potential to materially affect the value of our properties, the availability or the terms of financing and may impact the ability of our customers to enter into new leasing transactions or satisfy rental payments under existing leases. The uncertainty and pace of an economic recovery could also affect our operating results and financial condition as follows:

Debt and Equity Markets: Our results of operations and share price are sensitive to volatility in the credit markets. The commercial real estate debt markets have experienced significant volatility as a result of various factors, including the tightening of underwriting standards by lenders and credit rating agencies and the continued erosion of operating fundamentals of assets pledged as collateral. Credit spreads for major sources of capital widened significantly as investors have demanded a higher risk premium. This has resulted in lenders increasing the cost for debt financing. Should the overall cost of borrowings increase, either by increases in the index rates or by increases in lender spreads, we will need to factor such increases into the economics of our acquisitions. In addition, the state of the debt markets could have an effect on the overall amount of capital being invested in real estate, which may result in price or value decreases of real estate assets and affect our ability to raise capital.

Our ability to issue preferred shares or other sources of capital, such has borrowing, has been in the past, and may in the future, be adversely affected by challenging credit market conditions. The issuance of perpetual preferred securities historically has been a significant source of capital to grow our business. We believe that we have sufficient working capital and capacity under our credit facilities and our retained cash flow from operations to continue to operate our business as usual and meet our current obligations. However, if we were unable to issue preferred shares or borrow at reasonable rates, that could limit the earnings growth that might otherwise result from the acquisition and development of real estate facilities.

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Valuations: Market volatility has made the valuation of our properties more difficult. There may be significant uncertainty in the valuation, or in the stability of the value, of our properties, which could result in a substantial decrease in the value of our properties. As a result, we may not be able to recover the carrying amount of our properties, which may require us to recognize an impairment charge in earnings.

The acquisition of existing properties is a significant component of our long-term growth strategy, and acquisitions of existing properties are subject to risks that may adversely affect our growth and financial results.

We acquire existing properties, either in individual transactions or portfolios offered by other commercial real estate owners. In addition to the general risks related to real estate described above, we are also subject to the following risks which may jeopardize our realization of benefits from acquisitions.

Any failure to manage acquisitions and other significant transactions to achieve anticipated results and to successfully integrate acquired operations into our existing business could negatively impact our financial results: To fully realize anticipated earnings from an acquisition, we must successfully integrate the property into our operating platform. Failures or unexpected circumstances in the integration process, such as a failure to maintain existing relationships with tenants and employees due to changes in processes, standards, or compensation arrangements, or circumstances we did not detect during due diligence, could jeopardize realization of the anticipated earnings.

During 2011, we acquired 5.6 million square feet for an aggregate purchase price of $553.5 million. We continue to seek to acquire and develop flex, industrial and office properties where they meet our criteria all of which we believe will enhance our future financial performance and the value of our portfolio. Our belief, however, is subject to risks, uncertainties and other factors, many of which are forward-looking and are uncertain in nature or are beyond our control, including the risks that our acquisitions and developments may not perform as expected, that we may be unable to quickly integrate new acquisitions and developments into our existing operations, and that any costs to develop projects or redevelop acquired properties may exceed estimates. As of December 31, 2011, the aggregate occupancy of the assets acquired in 2011 was 80.5%. If the Company is unable to lease the vacant square footage of these properties in a reasonable period of time, it may not be able to achieve its objective of enhancing value. Further, we face significant competition for suitable acquisition properties from other real estate investors, including other publicly traded real estate investment trusts and private institutional investors. As a result, we may be unable to acquire additional properties we desire or the purchase price for desirable properties may be significantly increased.

In addition, some of these properties may have unknown characteristics or deficiencies or may not complement our portfolio of existing properties. We may also finance future acquisitions and developments through a combination of borrowings, proceeds from equity or debt offerings by us or the Operating Partnership, and proceeds from property divestitures. These financing options may not be available when desired or required or may be more costly than anticipated, which could adversely affect our cash flow. Real property development is subject to a number of risks, including construction delays, complications in obtaining necessary zoning, occupancy and other governmental permits, cost overruns, financing risks, and the possible inability to meet expected occupancy and rent levels. If any of these problems occur, development costs for a project may increase, and there may be costs incurred for projects that are not completed. As a result of the foregoing, some properties may be worth less or may generate less revenue than, or simply not perform as well as, we believed at the time of acquisition or development, negatively affecting our operating results. Any of the foregoing risks could adversely affect our financial condition, operating results and cash flow, and our ability to pay dividends on, and the market price of, our stock. In addition, we may be unable to successfully integrate and effectively manage the properties we do acquire and develop, which could adversely affect our results of operations.

Acquired properties are subject to property tax reappraisals which may increase our property tax expense: Facilities that we acquire are subject to property tax reappraisal which can result in substantial increases to the ongoing property taxes paid by the seller. The reappraisal process is subject to judgment of governmental agencies regarding estimated real estate values and other factors, and as a result there is a significant degree of uncertainty in estimating the property tax expense of an acquired property. In connection with future or recent

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acquisitions of properties, if our estimates of property taxes following reappraisal are too low, we may not realize anticipated earnings from an acquisition.

We acquire existing properties, either in individual transactions or portfolios offered by other commercial real estate owners. In addition to the general risks related to real estate described above, we are also subject to the following risks which may jeopardize our realization of benefits from acquisitions.

We would incur adverse tax consequences if we fail to qualify as a REIT.

Our cash flow would be reduced if we fail to qualify as a REIT: While we believe that we have qualified since 1990 to be taxed as a REIT, and will continue to be so qualified, we cannot be certain. To continue to qualify as a REIT, we need to satisfy certain requirements under the federal income tax laws relating to our income, assets, distributions to shareholders and shareholder base. In this regard, the share ownership limits in our articles of incorporation do not necessarily ensure that our shareholder base is sufficiently diverse for us to qualify as a REIT. For any year we fail to qualify as a REIT, we would be taxed at regular corporate tax rates on our taxable income unless certain relief provisions apply. Taxes would reduce our cash available for distributions to shareholders or for reinvestment, which could adversely affect us and our shareholders. Also we would not be allowed to elect REIT status for five years after we fail to qualify unless certain relief provisions apply.

We may need to borrow funds to meet our REIT distribution requirements: To qualify as a REIT, we must generally distribute to our shareholders 90% of our taxable income. Our income consists primarily of our share of our Operating Partnership’s income. We intend to make sufficient distributions to qualify as a REIT and otherwise avoid corporate tax. However, differences in timing between income and expenses and the need to make nondeductible expenditures such as capital improvements and principal payments on debt could force us to borrow funds to make necessary shareholder distributions.

PS has significant influence over us.

At December 31, 2011, PS owned 24.0% of the outstanding shares of the Company’s common stock and 23.2% of the outstanding common units of the Operating Partnership (100.0% of the common units not owned by the Company). Assuming issuance of the Company’s common stock upon redemption of its partnership units, PS would own 41.7% of the outstanding shares of the Company’s common stock. In addition, the PS Business Parks name and logo is owned by PS and licensed to the Company under a non-exclusive, royalty-free license agreement. The license can be terminated by either party for any reason with six months written notice. Ronald L. Havner, Jr., the Company’s chairman, is also Chairman of the Board, Chief Executive Officer and President of PS. Consequently, PS has the ability to significantly influence all matters submitted to a vote of our shareholders, including electing directors, changing our articles of incorporation, dissolving and approving other extraordinary transactions such as mergers, and all matters requiring the consent of the limited partners of the Operating Partnership. PS’s interest in such matters may differ from other shareholders. In addition, PS’s ownership may make it more difficult for another party to take over our Company without PS’s approval.

Provisions in our organizational documents may prevent changes in control.

Our articles generally prohibit any person from owning more than 7% of our shares: Our articles of incorporation restrict the number of shares that may be owned by any other person, and the partnership agreement of our Operating Partnership contains an anti-takeover provision. No shareholder (other than PS and certain other specified shareholders) may own more than 7% of the outstanding shares of our common stock, unless our board of directors waives this limitation. We imposed this limitation to avoid, to the extent possible, a concentration of ownership that might jeopardize our ability to qualify as a REIT. This limitation, however, also makes a change of control much more difficult (if not impossible) even if it may be favorable to our public shareholders. These provisions will prevent future takeover attempts not supported by PS even if a majority of our public shareholders consider it to be in their best interests as they would receive a premium for their shares over market value or for other reasons.

Our board can set the terms of certain securities without shareholder approval: Our board of directors is authorized, without shareholder approval, to issue up to 50.0 million shares of preferred stock and up to

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100.0 million shares of equity stock, in each case in one or more series. Our board has the right to set the terms of each of these series of stock. Consequently, the board could set the terms of a series of stock that could make it difficult (if not impossible) for another party to take over our Company even if it might be favorable to our public shareholders. Our articles of incorporation also contain other provisions that could have the same effect. We can also cause our Operating Partnership to issue additional interests for cash or in exchange for property.

The partnership agreement of our Operating Partnership restricts mergers: The partnership agreement of our Operating Partnership generally provides that we may not merge or engage in a similar transaction unless the limited partners of our Operating Partnership are entitled to receive the same proportionate payments as our shareholders. In addition, we have agreed not to merge unless the merger would have been approved had the limited partners been able to vote together with our shareholders, which has the effect of increasing PS’s influence over us due to PS’s ownership of operating partnership units. These provisions may make it more difficult for us to merge with another entity.

Our Operating Partnership poses additional risks to us.

Limited partners of our Operating Partnership, including PS, have the right to vote on certain changes to the partnership agreement. They may vote in a way that is against the interests of our shareholders. Also, as general partner of our Operating Partnership, we are required to protect the interests of the limited partners of the Operating Partnership. The interests of the limited partners and of our shareholders may differ.

We depend on external sources of capital to grow our Company.

We are generally required under the Internal Revenue Code to distribute at least 90% of our taxable income. Because of this distribution requirement, we may not be able to fund future capital needs, including any necessary building and tenant improvements, from operating cash flow. Consequently, we may need to rely on third-party sources of capital to fund our capital needs. We may not be able to obtain the financing on favorable terms or at all. Access to third-party sources of capital depends, in part, on general market conditions, the market’s perception of our growth potential, our current and expected future earnings, our cash flow, and the market price per share of our common stock. If we cannot obtain capital from third-party sources, we may not be able to acquire properties when strategic opportunities exist, satisfy any debt service obligations, or make cash distributions to shareholders.

We would incur adverse tax consequences if we fail to qualify as a REIT.

Our cash flow would be reduced if we fail to qualify as a REIT: While we believe that we have qualified since 1990 to be taxed as a REIT, and will continue to be so qualified, we cannot be certain. To continue to qualify as a REIT, we need to satisfy certain requirements under the federal income tax laws relating to our income, assets, distributions to shareholders and shareholder base. In this regard, the share ownership limits in our articles of incorporation do not necessarily ensure that our shareholder base is sufficiently diverse for us to qualify as a REIT. For any year we fail to qualify as a REIT, we would be taxed at regular corporate tax rates on our taxable income unless certain relief provisions apply. Taxes would reduce our cash available for distributions to shareholders or for reinvestment, which could adversely affect us and our shareholders. Also we would not be allowed to elect REIT status for five years after we fail to qualify unless certain relief provisions apply.

We may need to borrow funds to meet our REIT distribution requirements: To qualify as a REIT, we must generally distribute to our shareholders 90% of our taxable income. Our income consists primarily of our share of our Operating Partnership’s income. We intend to make sufficient distributions to qualify as a REIT and otherwise avoid corporate tax. However, differences in timing between income and expenses and the need to make nondeductible expenditures such as capital improvements and principal payments on debt could force us to borrow funds to make necessary shareholder distributions.

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We are subject to laws and governmental regulations and actions that affect our operating results and financial condition.

Our business is subject to regulation under a wide variety of U.S. federal, state and local laws, regulations and policies including those imposed by the SEC, the Sarbanes-Oxley Act of 2002, the Dodd-Frank Wall Street Reform and Consumer Protection Act and New York Stock Exchange, as well as applicable labor laws. Although we have policies and procedures designed to comply with applicable laws and regulations, failure to comply with the various laws and regulations may result in civil and criminal liability, fines and penalties, increased costs of compliance and restatement of our financial statements.

There can also be no assurance that, in response to current economic conditions or the current political environment or otherwise, laws and regulations will not be implemented or changed in ways that adversely affect our operating results and financial condition, such as recently adopted legislation that expands health care coverage costs or facilitates union activity or federal legislative proposals to otherwise increase operating costs.

Terrorist attacks and the possibility of wider armed conflict may have an adverse impact on our business and operating results and could decrease the value of our assets.

Terrorist attacks and other acts of violence or war could have a material adverse impact on our business and operating results. There can be no assurance that there will not be further terrorist attacks against the U.S. Attacks or armed conflicts that directly impact one or more of our properties could significantly affect our ability to operate those properties and thereby impair our operating results. Further, we may not have insurance coverage for losses caused by a terrorist attack. Such insurance may not be available, or if it is available and we decide to obtain such terrorist coverage, the cost for the insurance may be significant in relationship to the risk overall. In addition, the adverse effects that such violent acts and threats of future attacks could have on the U.S. economy could similarly have a material adverse effect on our business and results of operations. Finally, further terrorist acts could cause the U.S. to enter into a wider armed conflict, which could further impact our business and operating results.

Developments in California may have an adverse impact on our business and financial results.

We are headquartered in, and approximately 41.0% of our properties are located in California, which like many other state and local jurisdictions is facing severe budgetary problems and deficits. Actions that may be taken in response to these problems, such as increases in property taxes, changes to sales taxes or other governmental efforts to raise revenues could adversely impact our business and results of operations.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

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ITEM 2. PROPERTIES

As of December 31, 2011, the Company owned 102 business parks consisting of a geographically diverse portfolio of 27.2 million rentable square feet of commercial real estate which consists of 14.7 million square feet of flex space, 7.5 million square feet of industrial space and 5.0 million square feet of office space concentrated primarily in eight states consisting of California, Virginia, Florida, Texas, Maryland, Oregon, Arizona and Washington. The weighted average occupancy rate throughout 2011 was 89.2% and the realized rent per square foot was $15.24.

The following table reflects the geographical diversification of the 102 business parks owned by the Company as of December 31, 2011, the type of the rentable square footage and the weighted average occupancy rates throughout 2011 (except as set forth below, all of the properties are held in fee simple interest) (in thousands, except number of business parks):

We currently anticipate that each of the properties listed above will continue to be used for its current purpose. Competition exists in each of the market areas in which these properties are located.

The Company has no plans to change the current use of its properties. The Company typically renovates its properties in connection with the re-leasing of space to tenants and expects that it will pay the costs of such renovations from rental income. The Company has risks that tenants will default on leases and declare bankruptcy. Management believes these risks are mitigated through the Company’s geographic diversity and diverse tenant base.

The Company evaluates the performance of its business parks primarily based on net operating income (“NOI”). NOI is defined by the Company as rental income as defined by GAAP less cost of operations as defined by GAAP, excluding depreciation and amortization. The Company uses NOI and its components as a measurement of the performance of its commercial real estate. Management believes that these financial measures provide them, as well as the investor, the most consistent measurement on a comparative basis of the performance of the commercial real estate and its contribution to the value of the Company. Depreciation and amortization have been excluded from NOI as they are generally not used in determining the value of commercial real estate by management or the investment community. Depreciation and amortization are generally not used in determining value as they consider the historical costs of an asset compared to its current value; therefore, to understand the effect of the assets’ historical cost on the Company’s results, investors should look at GAAP financial measures, such as total operating costs including depreciation and amortization. The Company’s calculation of NOI may not be comparable to those of other companies and should not be used as an alternative to measures of performance calculated in accordance with GAAP. As part of the table below, we have reconciled total NOI to income from continuing operations, which we consider the most directly comparable financial measure calculated in accordance with GAAP. The following information illustrates rental income, cost

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of operations and NOI generated by the Company’s total portfolio in 2011, 2010 and 2009 by state and by property classifications. As a result of acquisitions and dispositions, certain properties were not held for the full year.

The Company’s calculation of NOI may not be comparable to those of other companies and should not be used as an alternative to measures of performance in accordance with GAAP. The tables below also include a reconciliation of NOI to the most comparable amounts based on GAAP (in thousands):

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The following table is provided to reconcile NOI to consolidated income from continuing operations as determined by GAAP (in thousands):

Portfolio Information

The table below sets forth information with respect to occupancy and rental rates of the Company’s total portfolio for each of the last five years, including discontinued operations:

The following table set forth the lease expirations for all assets in continuing operations as of December 31, 2011 (in thousands):

Lease Expirations as of December 31, 2011

ITEM 3. LEGAL PROCEEDINGS

We are not presently subject to material litigation nor, to our knowledge, is any material litigation threatened against us, other than routine actions for negligence and other claims and administrative proceedings arising in the ordinary course of business, some of which are expected to be covered by liability insurance or third party indemnifications and all of which collectively we do not expect to have a material adverse effect on our financial condition, results of operations, or liquidity.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

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PART II

Market Price of the Registrant’s Common Equity:

The common stock of the Company trades on the New York Stock Exchange under the symbol PSB. The following table sets forth the high and low sales prices of the common stock on the New York Stock Exchange for the applicable periods:

Holders:

As of February 20, 2012, there were 407 holders of record of the common stock.

Dividends:

Holders of common stock are entitled to receive distributions when, as and if declared by the Company’s Board of Directors out of any funds legally available for that purpose. The Company is required to distribute at least 90% of its taxable income prior to the filing of the Company’s tax return to maintain its REIT status for federal income tax purposes. It is management’s intention to pay distributions of not less than these required amounts.

Distributions paid per share of common stock for the years ended December 31, 2011 and 2010 amounted to $1.76 per year. The Board of Directors has established a distribution policy intended to maximize the retention of operating cash flow and distribute the minimum amount required for the Company to maintain its tax status as a REIT. Pursuant to restrictions contained in the Company’s Credit Facility, distributions may not exceed 95% of funds from operations, as defined therein, for any four consecutive quarters. For more information on the Credit Facility, see Note 5 to the consolidated financial statements.

Issuer Repurchases of Equity Securities:

The Company’s Board of Directors previously authorized the repurchase, from time to time, of up to 6.5 million shares of the Company’s common stock on the open market or in privately negotiated transactions. During the three months ended December 31, 2011, there were no shares of the Company’s common stock repurchased. As of December 31, 2011, the Company has 1,614,721 shares available for purchase under the program. The program does not expire. Purchases will be made subject to market conditions and other investment opportunities available to the Company.

Securities Authorized for Issuance Under Equity Compensation Plans:

The equity compensation plan information is provided in Item 12.

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ITEM 6. SELECTED FINANCIAL DATA

The following sets forth selected consolidated financial and operating information on a historical basis of the Company. The following information should be read in conjunction with the consolidated financial statements and notes thereto of the Company included elsewhere in this Form 10-K. Note that historical results from 2010 through 2007 were reclassified to conform to 2011 presentation for discontinued operations. See Note 3 to the consolidated financial statements included elsewhere in this Form 10-K for a discussion of income from discontinued operations.