PROSPERITY BANCSHARES INC - Annual Report: 2012 (Form 10-K)

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

OR

Commission File Number 001-35388

PROSPERITY BANCSHARES, INC.^®

(Exact name of registrant as specified in its charter)

Registrant’s Telephone Number, Including Area Code: (713) 693-9300

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  x    No  ¨

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  ¨    No  x

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  x    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 during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  x    No  ¨

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 of this Form 10-K.  x

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 the 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    x

The aggregate market value of the shares of common stock held by non-affiliates as of June 30, 2012, based on the closing price of the common stock on the NASDAQ Global Select Market on June 30, 2012 was approximately $1.83 billion.

As of February 15, 2013, the number of outstanding shares of common stock was 56,997,694.

Documents Incorporated by Reference:

Portions of the Company’s Proxy Statement relating to the 2013 Annual Meeting of Shareholders, which will be filed within 120 days after December 31, 2012, are incorporated by reference into Part III, Items 10-14 of this Annual Report on Form 10-K.

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PROSPERITY BANCSHARES, INC.^®

2012 ANNUAL REPORT ON FORM 10-K

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PART I

ITEM 1. BUSINESS

General

Prosperity Bancshares, Inc.^®, a Texas corporation (the “Company”), was formed in 1983 as a vehicle to acquire the former Allied Bank in Edna, Texas which was chartered in 1949 as The First National Bank of Edna and is now known as Prosperity Bank. The Company is a registered financial holding company that derives substantially all of its revenues and income from the operation of its bank subsidiary, Prosperity Bank^® (“Prosperity Bank^®” or the “Bank”). The Bank provides a broad line of financial products and services to small and medium-sized businesses and consumers. As of December 31, 2012, the Bank operated two hundred thirteen (213) full service banking locations; fifty-nine (59) in the Houston area; twenty (20) in the South Texas area including Corpus Christi and Victoria; thirty-five (35) in the Dallas/Fort Worth area; twenty-one (21) in the East Texas area; thirty-four (34) in the Central Texas area including Austin and San Antonio; thirty-four (34) in the West Texas area including Lubbock, Midland-Odessa and Abilene; and ten (10) in the Bryan/College Station area. The Company added a net of two (2) banking centers in Tyler, TX in connection with its acquisition of East Texas Financial Services (“East Texas”) on January 1, 2013, after consolidations. The Company’s headquarters are located at Prosperity Bank Plaza, 4295 San Felipe in Houston, Texas and its telephone number is (713) 693-9300. The Company’s website address is www.prosperitybanktx.com.

The Company’s market consists of the communities served by its banking centers. The diverse nature of the economies in each local market served by the Company provides the Company with a varied customer base and allows the Company to spread its lending risk throughout a number of different industries including professional service firms and their principals, manufacturing, tourism, recreation, petrochemicals, farming and ranching. The Company’s market areas outside of Houston, Dallas, Corpus Christi, San Antonio and Austin are dominated by either small community banks or branches of large regional banks. Management believes that the Company, as one of the few mid-sized financial institutions that combines responsive community banking with the sophistication of a regional bank holding company, has a competitive advantage in its market areas and excellent growth opportunities through acquisitions, including acquisitions of failed financial institutions, new banking center locations and additional business development.

Operating under a community banking philosophy, the Company seeks to develop broad customer relationships based on service and convenience while maintaining its conservative approach to lending and sound asset quality. The Company has grown through a combination of internal growth, the acquisition of community banks and branches of banks and the opening of new banking centers. Utilizing a low cost of funds and employing stringent cost controls, the Company has been profitable in every year of its existence, including the periods of adverse economic conditions in Texas in the late 1980s and more recently in 2009 and 2010. From 1988 to 1992 as a sound and profitable institution, the Company took advantage of this economic downturn and acquired the deposits and certain assets of failed banks in West Columbia, El Campo and Cuero, Texas and two failed banks in Houston, which diversified the Company’s franchise and increased its core deposits. The Company opened a full-service banking center in Victoria, Texas in 1993 and the following year established a banking center in Bay City, Texas. The Company expanded its Bay City presence in 1996 with the acquisition of an additional branch location from Norwest Bank Texas (now Wells Fargo), and in 1997, the Company acquired the Angleton, Texas branch of Wells Fargo Bank. In 1998, the Company enhanced its West Columbia Banking Center with the purchase of a commercial bank branch located in West Columbia and acquired Union State Bank in East Bernard, Texas. In 2008, the Company again took advantage of the economic downturn and acquired approximately $3.6 billion in deposits and certain assets of Franklin Bank headquartered in Houston, Texas from the Federal Deposit Insurance Corporation (“FDIC”), as receiver. In 2010, the Company further expanded its presence with the acquisition of twenty-two (22) banking centers through two separate branch acquisition transactions. These transactions significantly increased the Company’s presence in the Dallas/Fort Worth area.

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From December 31, 2002 through December 31, 2012, the Company grew through internal growth and the completion of the following acquisitions:

Pending and Recent Acquisitions

Acquisition of Texas Bankers, Inc.—On January 1, 2012, the Company completed the acquisition of Texas Bankers, Inc. and its wholly-owned subsidiary, Bank of Texas, Austin, Texas. The three (3) Bank of Texas banking offices in the Austin, Texas CMSA consisted of a location in Rollingwood, which was consolidated with the Company’s Westlake location and remains in Bank of Texas’ Rollingwood banking office; one banking center in downtown Austin, which was consolidated into the Company’s downtown Austin location; and another banking center in Thorndale.

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Texas Bankers, Inc. on a consolidated basis, reported total assets of $77.0 million, total loans of $27.6 million and total deposits of $70.4 million as of December 31, 2011. Under the terms of the acquisition agreement, the Company issued 314,953 shares of Company common stock for all outstanding shares of Texas Bankers capital stock, resulting in an acquisition date fair value of $12.7 million, based on the Company’s closing stock price of $40.35. The Company recognized goodwill of $6.1 million which is calculated as the excess of both the consideration exchanged and liabilities assumed as compared to the fair value of identifiable assets acquired.

Acquisition of The Bank Arlington—On April 1, 2012, the Company completed the acquisition of The Bank Arlington. The Bank Arlington operated one banking office in Arlington, Texas, in the Dallas/Fort Worth CMSA.

As of March 31, 2012, The Bank Arlington reported total assets of $37.3 million, total loans of $22.9 million and total deposits of $33.2 million. Under the terms of the acquisition agreement, the Company issued 135,347 shares of Company common stock for all outstanding shares of The Bank Arlington capital stock, resulting in an acquisition date fair value of $6.2 million, based on the Company’s closing stock price of $45.80. The Company recognized goodwill of $2.1 million which is calculated as the excess of both the consideration exchanged and liabilities assumed as compared to the fair value of identifiable assets acquired.

Acquisition of American State Financial Corporation—On July 1, 2012, the Company completed the acquisition of American State Financial Corporation and its wholly owned subsidiary American State Bank (collectively referred to as “ASB”). ASB operated thirty-seven (37) full service banking offices in eighteen (18) counties across West Texas.

On the date of acquisition, the Company recorded total assets of $3.11 billion, total loans of $1.15 billion and total deposits of $2.50 billion. Under the terms of the acquisition agreement, the Company issued 8,524,835 shares of Company common stock plus $178.5 million in cash for all outstanding shares of American State Financial Corporation capital stock, for total merger consideration of $536.8 million and recognized goodwill of $274.1 million.

Acquisition of Community National Bank—On October 1, 2012, the Company completed the acquisition of Community National Bank, Bellaire, Texas. Community National Bank operated one (1) banking office in Bellaire, Texas, in the Houston Metropolitan Area.

As of September 30, 2012, Community National Bank reported total assets of $182.0 million, total loans of $68.0 million and total deposits of $164.6 million. Under the terms of the acquisition agreement, the Company issued 372,282 shares of Company common stock plus $11.4 million in cash for all outstanding shares of Community National Bank capital stock, for total merger consideration of $27.3 million, based on the Company’s closing stock price of $42.62 .The Company recognized goodwill of $10.3 million which is calculated as the excess of both the consideration exchanged and liabilities assumed as compared to the fair value of identifiable assets acquired.

Acquisition of East Texas Financial Services, Inc.—On January 1, 2013, the Company completed the previously announced acquisition of East Texas Financial Services, Inc. (OTC BB: FFBT) and its wholly-owned subsidiary, First Federal Bank Texas (“Firstbank”). Firstbank operated four (4) banking offices in the Tyler MSA, including three locations in Tyler, Texas and one location in Gilmer, Texas. As of December 31, 2012, East Texas Financial Services reported, on a consolidated basis, total assets of $165.0 million, total loans of $129.3 million and total deposits of $112.3 million.

Pursuant to the terms of the acquisition agreement, the Company issued 530,940 shares of the Company common stock for all outstanding shares of East Texas Financial Services capital stock resulting in an acquisition date fair value of $22.3 million, based on the Company’s closing stock price of $42.00 and recognized goodwill

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of approximately $5.5 million which is calculated as the excess of both the consideration exchanged and liabilities assumed compared to the fair value of the assets acquired. The Company is currently in the process of obtaining fair values for certain acquired assets and assumed liabilities and therefore the estimates are preliminary.

Pending Acquisition of Coppermark Bancshares Inc.—On December 10, 2012, the Company entered into a definitive agreement to acquire Coppermark Bancshares, Inc. and its wholly-owned subsidiary, Coppermark Bank (“Coppermark”) headquartered in Oklahoma City, Oklahoma. Coppermark operates nine (9) full-service banking offices: six (6) in Oklahoma City, Oklahoma and surrounding areas and three (3) in the Dallas, Texas area. As of December 31, 2012, Coppermark reported, on a consolidated basis, total assets of $1.3 billion, total loans of $853.4 million and total deposits of $1.2 billion.

Under the terms of the acquisition agreement, the Company will issue approximately 3,258,845 shares of the Company’s common stock plus $60.0 million in cash for all outstanding shares of Coppermark Bancshares capital stock, subject to certain conditions and potential adjustments. Pending the satisfaction of closing conditions, the closing is expected to occur in early 2013.

Available Information

The Company’s website address is www.prosperitybanktx.com. The Company makes available free of charge on or through its website its Annual Report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and all amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (“Exchange Act”), as soon as reasonably practicable after such material is electronically filed with or furnished to the Securities and Exchange Commission. Information contained on the Company’s website is not incorporated by reference into this Annual Report on Form 10-K and is not part of this or any other report.

Officers and Associates

The Company’s directors and officers are important to the Company’s success and play a key role in the Company’s business development efforts by actively participating in civic and public service activities in the communities served by the Company.

The Company has invested heavily in its officers and associates by recruiting talented officers in its market areas and providing them with economic incentives in the form of stock-based compensation and bonuses based on cross-selling performance. The senior management team has substantial experience in the Houston, Dallas, Austin, Bryan/College Station, East Texas, Corpus Christi, San Antonio and West Texas markets and the surrounding communities in which the Company has a presence. Each banking center location is administered by a local president or manager with knowledge of the community and lending expertise in the specific industries found in the community. The Company entrusts its banking center presidents and managers with authority and flexibility within general parameters with respect to product pricing and decision making in order to avoid the bureaucratic structure of larger banks. The Company operates each banking center as a separate profit center, maintaining separate data with respect to each banking center’s net interest income, efficiency ratio, deposit growth, loan growth and overall profitability. Banking center presidents and managers are accountable for performance in these areas and compensated accordingly. The Company’s local banking centers have no 1-800 telephone numbers. Each banking center has its own listed local business telephone number. Customers are served by a local banker with decision making authority.

As of December 31, 2012, the Company and the Bank had 2,266 full-time equivalent associates, 817 of whom were officers of the Bank. The Company provides medical and hospitalization insurance to its full-time associates. The Company considers its relations with associates to be good. Neither the Company nor the Bank is a party to any collective bargaining agreement.

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Banking Activities

The Company, through the Bank, offers a variety of traditional loan and deposit products to its customers, which consist primarily of consumers and small and medium-sized businesses. The Bank tailors its products to the specific needs of customers in a given market. At December 31, 2012, the Bank maintained approximately 489,000 separate deposit accounts including certificates of deposit, 45,000 separate loan accounts and 25.9% of the Bank’s total deposits were noninterest-bearing demand deposits. For the year ended December 31, 2012, the Company’s average cost of funds was 0.37% and the Company’s average cost of deposits (excluding all borrowings) was 0.35%.

The Company has been an active real estate lender, with commercial real estate and 1-4 family residential loans comprising 35.9% and 24.2% of the Company’s total loans as of December 31, 2012, respectively. The Company also offers commercial loans, loans for automobiles and other consumer durables, home equity loans, debit cards, internet banking and other cash management services, mobile banking, trust and wealth management, retail brokerage services and automated telephone banking. By offering certificates of deposit, interest checking accounts, savings accounts and overdraft protection at competitive rates, the Company gives its depositors a full range of traditional deposit products.

The businesses targeted by the Company in its lending efforts are primarily those that require loans in the $100 thousand to $8.0 million range. The Company offers these businesses a broad array of loan products including term loans, lines of credit and loans for working capital, business expansion and the purchase of equipment and machinery, interim construction loans for builders and owner-occupied commercial real estate loans.

The Company also maintains a trust department with $896 million in assets under management as of December 31, 2012, acquired in connection with the ASB acquisition. The trust department provides personal trust services and presently operates in the Company’s West Texas area.

Business Strategies

The Company’s main objective is to increase deposits and loans internally, as well as through additional expansion opportunities and acquisitions, while maintaining efficiency and individualized customer service and maximizing profitability. To achieve this objective, the Company has employed the following strategic goals:

Continue Community Banking Emphasis. The Company intends to continue operating as a community banking organization focused on meeting the specific needs of consumers and small and medium-sized businesses in its market areas. The Company provides a high degree of responsiveness combined with a wide variety of banking products and services. The Company staffs its banking centers with experienced bankers with lending expertise in the specific industries found in the given community, and gives them authority to make certain pricing and credit decisions, avoiding the bureaucratic structure of larger banks.

Expand Market Share Through Internal Growth and a Disciplined Acquisition Strategy. The Company intends to continue seeking opportunities, both inside and outside its existing markets, to expand either by acquiring existing banks or branches of banks, including FDIC assisted purchases, or by establishing new banking centers. All of the Company’s acquisitions have been accretive to earnings within 12 months after acquisition date and generally have supplied the Company with relatively low-cost deposits which have been used to fund the Company’s lending and investing activities. However, the Company makes no guarantee that future acquisitions, if any, will be accretive to earnings within any particular time period. Factors used by the Company to evaluate expansion opportunities include (i) the similarity in management and operating philosophies, (ii) whether the acquisition will be accretive to earnings and enhance shareholder value, (iii) the ability to improve the efficiency ratio through economies of scale, (iv) whether the acquisition will strategically expand the Company’s geographic footprint, and (v) the opportunity to enhance the Company’s market presence in existing market areas.

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Increase Loan Volume and Diversify Loan Portfolio. While maintaining its conservative approach to lending, the Company has emphasized both new and existing loan products, focusing on managing its commercial real estate and commercial loan portfolios. The Company’s loan portfolio increased $1.41 billion during 2012 of which approximately $1.27 billion was the result of four acquisitions completed during the year. During the one year period from December 31, 2011 to December 31, 2012, the Company’s commercial and industrial loans increased from $406.4 million to $771.1 million, or 89.7%, and represented 10.8% and 14.9% of the total portfolio, respectively for the same period. Commercial real estate increased from $1.35 billion to $1.85 billion, or 37.1%, and represented 35.9% of the total portfolio, for both periods. In addition, the Company targets professional service firms, including legal and medical practices, for both loans secured by owner-occupied premises and personal loans to their principals.

Maintain Sound Asset Quality. The Company continues to maintain the sound asset quality that has been representative of its historical loan portfolio. As the Company continues to diversify and increase its lending activities and acquire loans in acquisitions, it may face higher risks of nonpayment and increased risks in the event of continued economic downturns. The Company intends to continue to employ the strict underwriting guidelines and comprehensive loan review process that have contributed to its low incidence of nonperforming assets and its minimal charge-offs in relation to its size.

Continue Focus on Efficiency. The Company plans to maintain its stringent cost control practices and policies. The Company has invested significantly in the infrastructure required to centralize many of its critical operations, such as data processing and loan processing. For its banking centers, which the Company operates as independent profit centers, the Company supplies complete support in the areas of loan review, internal audit, compliance and training. Management believes that this centralized infrastructure can accommodate additional growth while enabling the Company to minimize operational costs through economies of scale.

Enhance Cross-Selling. The Company recognizes that its customer base provides significant opportunities to cross-sell various products and it seeks to develop broader customer relationships by identifying cross-selling opportunities. The Company uses incentives and friendly competition to encourage cross-selling efforts and increase cross-selling results among its associates. Officers and associates have access to each customer’s existing and related account relationships and are better able to inform customers of additional products when customers visit or call the various banking centers or use their drive-in facilities. In addition, the Company includes product information in monthly statements and other mailings.

Competition

The banking business is highly competitive, and the profitability of the Company depends principally on its ability to compete in its market areas. The Company competes with other commercial banks, savings banks, savings and loan associations, credit unions, finance companies, mutual funds, insurance companies, brokerage and investment banking firms, asset-based nonbank lenders and certain other nonfinancial entities, including retail stores which may maintain their own credit programs and certain governmental organizations which may offer more favorable financing than the Company. The Company believes it has been able to compete effectively with other financial institutions by emphasizing customer service, technology and responsive decision-making with respect to loans, by establishing long-term customer relationships and building customer loyalty and by providing products and services designed to address the specific needs of its customers.

Supervision and Regulation

The supervision and regulation of bank holding companies and their subsidiaries is intended primarily for the protection of depositors, the Deposit Insurance Fund (“DIF”) of the FDIC and the banking system as a whole, and not for the protection of the bank holding company’s shareholders or creditors. The banking agencies have broad enforcement power over bank holding companies and banks including the power to impose substantial fines and other penalties for violations of laws and regulations.

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The following description summarizes some of the laws to which the Company and the Bank are subject. References in this Annual Report on Form 10-K to applicable statutes and regulations are brief summaries thereof, do not purport to be complete, and are qualified in their entirety by reference to such statutes and regulations.

The Company

The Company is a financial holding company pursuant to the Gramm-Leach-Bliley Act and a bank holding company registered under the Bank Holding Company Act of 1956, as amended (“BHCA”). Accordingly, the Company is subject to supervision, regulation and examination by the Board of Governors of the Federal Reserve System (“Federal Reserve Board”). The Gramm-Leach-Bliley Act, the BHCA and other federal laws subject financial and bank holding companies to particular restrictions on the types of activities in which they may engage, and to a range of supervisory requirements and activities, including regulatory enforcement actions for violations of laws and regulations.

Regulatory Restrictions on Dividends. The Company is regarded as a legal entity separate and distinct from the Bank. The principal source of the Company’s revenues is dividends received from the Bank. As described in more detail below, federal law places limitations on the amount that state banks may pay in dividends, which the Bank must adhere to when paying dividends to the Company. It is the policy of the Federal Reserve Board that bank holding companies should pay cash dividends on common stock only out of income available over the past year and only if the prospective rate of earnings retention is consistent with the organization’s expected capital needs and financial condition. The Federal Reserve Board’s policy provides that bank holding companies should not maintain a level of cash dividends that undermines the bank holding company’s ability to serve as a source of strength to its banking subsidiaries. The Federal Reserve Board is authorized to limit or prohibit the payment of dividends if, in the Federal Reserve Board’s opinion, the payment of dividends would constitute an unsafe or unsound practice in light of a bank holding company’s financial condition. In addition, the Federal Reserve Board has indicated that each bank holding company should carefully review its dividend policy, and has discouraged payment ratios that are at maximum allowable levels, which is the maximum dividend amount that may be issued and allow the company to still maintain its target Tier 1 capital ratio, unless both asset quality and capital are very strong.

Stress Testing. Pursuant to the Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act”), in October 2012 the Federal Reserve Board published its final rules regarding company-run stress testing. The rules will require institutions with average total consolidated assets greater than $10 billion, such as the Company and the Bank, to conduct an annual company-run stress test of capital and consolidated earnings and losses under one base and at least two stress scenarios provided by bank regulatory agencies. Pursuant to the rules, institutions with total consolidated assets between $10 billion and $50 billion are to use data as of September 30, 2013 to conduct the stress test, using scenarios that are to be released by the agencies in November 2013. The results of stress tests must be reported to the agencies in March 2014. Public disclosure of summary stress test results under the severely adverse scenario will begin in June 2015 for stress tests commencing in 2014. It is anticipated that the Company’s capital ratios reflected in the stress test calculations will be an important factor considered by the Federal Reserve Board in evaluating whether proposed payments of dividends or stock repurchases may be an unsafe or unsound practice.

Source of Strength. Under Federal Reserve Board policy, a bank holding company has historically been required to act as a source of financial strength to each of its banking subsidiaries. The Dodd-Frank Act codified this policy as a statutory requirement. Under this requirement, the Company is expected to commit resources to support the Bank, including support at times when the Company may not be in a financial position to provide such resources. Any capital loans by a bank holding company to any of its subsidiary banks are subordinate in right of payment to deposits and to certain other indebtedness of such subsidiary banks. As discussed below, a bank holding company, in certain circumstances, could be required to guarantee the capital plan of an undercapitalized banking subsidiary.

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In the event of a bank holding company’s bankruptcy under Chapter 11 of the U.S. Bankruptcy Code, the trustee will be deemed to have assumed and is required to cure immediately any deficit under any commitment by the debtor holding company to any of the federal banking agencies to maintain the capital of an insured depository institution. Any claim for breach of such obligation will generally have priority over most other unsecured claims.

Scope of Permissible Activities. Under the BHCA, bank holding companies generally may not acquire a direct or indirect interest in or control of more than 5% of the voting shares of any company that is not a bank or bank holding company or from engaging in activities other than those of banking, managing or controlling banks or furnishing services to or performing services for its subsidiaries, except that it may engage in, directly or indirectly, certain activities that the Federal Reserve Board has determined to be so closely related to banking or managing and controlling banks as to be a proper incident thereto. In approving acquisitions or the addition of activities, the Federal Reserve Board considers, among other things, whether the acquisition or the additional activities can reasonably be expected to produce benefits to the public, such as greater convenience, increased competition, or gains in efficiency, that outweigh such possible adverse effects as undue concentration of resources, decreased or unfair competition, conflicts of interest or unsound banking practices.

Notwithstanding the foregoing, the Gramm-Leach-Bliley Act, effective March 11, 2000, eliminated the barriers to affiliations among banks, securities firms, insurance companies and other financial service providers and permits bank holding companies to become financial holding companies and thereby affiliate with securities firms and insurance companies and engage in other activities that are financial in nature. The Gramm-Leach- Bliley Act defines “financial in nature” to include securities underwriting, dealing and market making; sponsoring mutual funds and investment companies; insurance underwriting and agency; merchant banking activities; and activities that the Federal Reserve Board has determined to be closely related to banking. No regulatory approval will be required for a financial holding company, such as the Company, to acquire a company, other than a bank or savings association, engaged in activities that are financial in nature or incidental to activities that are financial in nature, as determined by the Federal Reserve Board.

The Company’s financial holding company status depends upon it maintaining its status as “well capitalized” and “well managed” under applicable Federal Reserve Board regulations. If a financial holding company ceases to meet these requirements, the Federal Reserve Board may impose corrective capital and/or managerial requirements on the financial holding company and place limitations on its ability to conduct the broader financial activities permissible for financial holding companies. Until the financial holding company returns to compliance, the company may not acquire a company engaged in such financial activities without prior approval of the Federal Reserve Board. In addition, the Federal Reserve Board may require divestiture of the holding company’s depository institutions and/or its non-bank subsidiaries if the deficiencies persist.

While the Federal Reserve Board is the “umbrella” regulator for financial holding companies and has the power to examine banking organizations engaged in new activities, regulation and supervision of activities which are financial in nature or determined to be incidental to such financial activities will be handled along functional lines. Accordingly, activities of subsidiaries of a financial holding company will be regulated by the agency or authorities with the most experience regulating that activity as it is conducted in a financial holding company.

The Dodd-Frank Act amends the BHCA to require the federal financial regulatory agencies to adopt rules that prohibit banks and their affiliates from engaging in proprietary trading and investing in and sponsoring certain unregistered investment companies. This statutory provision, commonly known as the “Volcker Rule,” defines unregistered investment companies as hedge funds and private equity funds. In November 2011, federal regulators proposed rules to implement the Volcker Rule after a comment period, no later than July 2012. As proposed, financial institutions would have a two year period, until July 21, 2014, following implementation of the final rules to bring affected activities into conformance with the Volcker Rule, subject to extension for up to three additional years. In early 2012, following the comment period, regulators announced that they would not be

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able to meet the July 2012 deadline. At present, lawmakers continue to work on drafting the final rules. The proposed rules are highly complex, and many aspects of their application remain uncertain. Based on the proposed rules, the Company does not currently anticipate that the Volcker Rule will have a material effect on the operations of the Company and the Bank, as the Company does not engage in the businesses prohibited by the Volcker Rule. The Company may incur costs if it is required to adopt additional policies and systems to ensure compliance with the Volcker Rule, but any such costs are not expected to be material. Until a final rule is adopted, the precise financial impact of the rule on the Company, its customers or the financial industry more generally, cannot be determined.

Safe and Sound Banking Practices. Bank holding companies are not permitted to engage in unsafe and unsound banking practices. The Federal Reserve Board’s Regulation Y, for example, generally requires a holding company to give the Federal Reserve Board prior notice of any redemption or repurchase of its own equity securities, if the consideration to be paid, together with the consideration paid for any repurchases or redemptions in the preceding year, is equal to 10% or more of the company’s consolidated net worth. The Federal Reserve Board may oppose the transaction if it believes that the transaction would constitute an unsafe or unsound practice or would violate any law or regulation. Depending upon the circumstances, the Federal Reserve Board could take the position that paying a dividend would constitute an unsafe or unsound banking practice.

The Federal Reserve Board has broad authority to prohibit activities of bank holding companies and their nonbanking subsidiaries which represent unsafe and unsound banking practices or which constitute violations of laws or regulations, and can assess civil money penalties for certain activities conducted on a knowing and reckless basis, if those activities caused a substantial loss to a depository institution. The penalties can be as high as $1.0 million for each day the activity continues.

Anti-Tying Restrictions. Bank holding companies and their affiliates are prohibited from tying the provision of certain services, such as extensions of credit, to other services offered by a holding company or its affiliates.

Capital Adequacy Requirements. The Federal Reserve Board has adopted a system using risk-based capital guidelines under a two-tier capital framework to evaluate the capital adequacy of bank holding companies. Tier 1 capital generally consists of common stockholders’ equity, retained earnings, a limited amount of qualifying perpetual preferred stock, qualifying trust preferred securities and noncontrolling interests in the equity accounts of consolidated subsidiaries, less goodwill and certain intangibles. Tier 2 capital generally consists of certain hybrid capital instruments and perpetual debt, mandatory convertible debt securities and a limited amount of subordinated debt, qualifying preferred stock, loan loss allowance, and unrealized holding gains on certain equity securities.

Under the guidelines, specific categories of assets are assigned different risk weights, based generally on the perceived credit risk of the asset. These risk weights are multiplied by corresponding asset balances to determine a “risk-weighted” asset base. The guidelines require a minimum ratio of total capital to total risk-weighted assets of 8.0% (of which at least 4.0% is required to consist of Tier 1 capital elements). Total capital is the sum of Tier 1 and Tier 2 capital. As of December 31, 2012, the Company’s ratio of Tier 1 capital to total risk-weighted assets was 14.40% and its ratio of total capital to total risk-weighted assets was 15.22%. Risk-weighted assets exclude intangible assets such as goodwill and core deposit intangibles.

In addition to the risk-based capital guidelines, the Federal Reserve Board uses a leverage ratio as an additional tool to evaluate the capital adequacy of bank holding companies. The leverage ratio is a company’s Tier 1 capital divided by its average total consolidated assets. Certain highly rated bank holding companies may maintain a minimum leverage ratio of 3.0%, but other bank holding companies are required to maintain a leverage ratio of 4.0%. As of December 31, 2012, the Company’s leverage ratio was 7.10%.

The federal banking agencies’ risk-based and leverage capital ratios are minimum supervisory ratios generally applicable to banking organizations that meet certain specified criteria. Banking organizations not meeting these criteria are expected to operate with capital positions well above the minimum ratios. The federal

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bank regulatory agencies may set capital requirements for a particular banking organization that are higher than the minimum ratios when circumstances warrant. Federal Reserve Board guidelines also provide that banking organizations experiencing internal growth or making acquisitions will be expected to maintain strong capital positions substantially above the minimum supervisory levels, without significant reliance on intangible assets.

Proposed Capital Adequacy Requirements. In June 2012, the Company’s primary federal regulator, the Federal Reserve Board, published two notices of proposed rulemaking (the “2012 Capital Proposals”) that would substantially revise the risk-based capital requirements applicable to bank holding companies and depository institutions, including the Company and the Bank. One of the 2012 Capital Proposals (the “Basel III Proposal”) addresses the components of capital and other issues affecting the numerator in banking institutions’ regulatory capital ratios and would implement the Basel Committee’s December 2010 framework for strengthening international capital standards, commonly known as “Basel III.” The other proposal (the “Standardized Approach Proposal”) addresses risk weights and other issues affecting the denominator in banking institutions’ regulatory capital ratios and would replace the existing Basel I-derived risk-weighting approach with a more risk-sensitive approach based, in part, on the standardized approach in the Basel Committee’s 2004 capital accords. The 2012 Capital Proposals would also implement the requirements of Section 939A of the Dodd-Frank Act to remove references to credit ratings from the federal banking agencies’ rules. As proposed, the Basel III Proposal and the Standardized Approach Proposal would come into effect on January 1, 2013 (subject to a phase-in period) and January 1, 2015 (with an option for early adoption), respectively. Final rules, however, have not yet been adopted, and the Basel III framework is therefore not yet applicable to the Company or the Bank.

The Basel III Proposal, among other things, (i) introduces a new capital measure: “Common Equity Tier 1” (“CET1”), (ii) specifies that Tier 1 capital consists of CET1 and “Additional Tier 1 capital” instruments meeting specified requirements, (iii) defines CET1 narrowly by requiring that most deductions and adjustments to regulatory capital measures be made to CET1 and not to the other components of capital and (iv) expands the scope of the deductions and adjustments as compared to existing regulations.

In addition, the Basel III Proposal provides for two distinct buffers of capital designed to protect the banking system as a whole during periods of systemic risk. One of the proposed buffers, a “capital conservation buffer,” is designed to absorb losses during periods of economic stress. The other, a “countercyclical capital buffer,” may be imposed by bank regulatory agencies where there is excess aggregate credit growth coupled with increasing systemic risk. The “countercyclical capital buffer” is applicable to only certain covered institutions and is not expected to have any current applicability to the Company or the Bank. Banking institutions with a ratio of CET1 to risk-weighted assets above the minimum but below the conservation buffer (or below the combined capital conservation buffer and countercyclical capital buffer, when the latter is applied) will face constraints on dividends, equity repurchases and compensation based on the amount of the shortfall.

Under the Basel III Proposal, the initial minimum capital ratios were to be the following: (i) 3.5% CET1 to risk-weighted assets, (ii) 4.5% Tier 1 capital to risk-weighted assets and (iii) 8.0% Total capital to risk-weighted assets.

When fully phased in on January 1, 2019, the Basel III Proposal will require the Bank to maintain (i) a minimum ratio of CET1 to risk-weighted assets of at least 4.5%, plus a 2.5% “capital conservation buffer” (which is added to the 4.5% CET1 ratio as that buffer is phased in, effectively resulting in a minimum ratio of CET1 to risk-weighted assets of at least 7% upon full implementation), (ii) a minimum ratio of Tier 1 capital to risk-weighted assets of at least 6.0%, plus the capital conservation buffer (which is added to the 6.0% Tier 1 capital ratio as that buffer is phased in, effectively resulting in a minimum Tier 1 capital ratio of 8.5% upon full implementation), (iii) a minimum ratio of total (that is, Tier 1 plus Tier 2) capital to risk-weighted assets of at least 8.0%, plus the capital conservation buffer (which is added to the 8.0% total capital ratio as that buffer is phased in, effectively resulting in a minimum total capital ratio of 10.5% upon full implementation) and (iv) a minimum leverage ratio of 4%, calculated as the ratio of Tier 1 capital to average assets.

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The Basel III Proposal provides for a number of deductions from and adjustments to CET1. These include, for example, the requirement that mortgage servicing rights, deferred tax assets dependent upon future taxable income and significant investments in non-consolidated financial entities be deducted from CET1 to the extent that any one such category exceeds 10% of CET1 or all such categories in the aggregate exceed 15% of CET1. Under current capital standards, the effects of accumulated other comprehensive income items included in capital are excluded for the purposes of determining regulatory capital ratios. Under the Basel III Proposal, the effects of certain accumulated other comprehensive items are not excluded, which could result in significant variations in the level of capital depending upon the impact of interest rate fluctuations on the fair value of the Company’s securities portfolio. The Basel III Proposal also requires the phase-out of certain hybrid securities, such as trust preferred securities, as Tier 1 capital of bank holding companies in equal installments. Trust preferred securities no longer included in Tier 1 capital may nonetheless be included as a component of Tier 2 capital.

Implementation of the deductions and other adjustments to CET1 will begin on January 1, 2014 and will be phased-in over a five-year period (20% per year). The implementation of the capital conservation buffer will begin on January 1, 2016 at the 0.625% level and be phased in over a four-year period (increasing by that amount on each subsequent January 1, until it reaches 2.5% on January 1, 2019).

With respect to the Bank, the Basel III Proposal would also revise the “prompt corrective action” regulations pursuant to Section 38 of the Federal Deposit Insurance Act, by (i) introducing a CET1 ratio requirement at each level (other than critically undercapitalized), with the required CET1 ratio being 6.5% for well-capitalized status; (ii) increasing the minimum Tier 1 capital ratio requirement for each category, with the minimum Tier 1 capital ratio for well-capitalized status being 8% (as compared with the current 6%); and (iii) eliminating the current provision that provides that a bank with a composite supervisory rating of 1 may have a 3% leverage ratio and still be adequately capitalized. The Basel III Proposal does not change the total risk-based capital requirement for any category.

Proposed Liquidity Requirements. Historically, regulation and monitoring of bank and bank holding company liquidity has been addressed as a supervisory matter, without required formulaic measures. The Basel III liquidity framework requires banks and bank holding companies to measure their liquidity against specific liquidity tests that, although similar in some respects to liquidity measures historically applied by banks and regulators for management and supervisory purposes, will be required by regulation going forward. However, the federal banking agencies have not proposed rules implementing the Basel III liquidity framework and have not determined to what extent they will apply to banks that are not large, internationally active banks.

One test, referred to as the liquidity coverage ratio (“LCR”), is designed to ensure that a banking entity maintains an adequate level of unencumbered high-quality liquid assets equal to the entity’s expected net cash outflow for a 30-day time horizon (or, if greater, 25% of its expected total cash outflow) under an acute liquidity stress scenario. The other test, referred to as the net stable funding ratio (“NSFR”), is designed to promote more medium- and long-term funding of the assets and activities of banking entities over a one-year time horizon. These requirements will provide banking entities with incentives to increase their holdings of U.S. Treasury securities and other sovereign debt as a component of assets and increase the use of long-term debt as a funding source. The Basel III liquidity framework contemplates that the LCR will be subject to an observation period continuing through mid-2013 and subject to any revisions resulting from the analyses conducted and data collected during the observation period, will be implemented as minimum standards on January 1, 2015, with a phase-in period ending January 1, 2019. Similarly, the Basel III liquidity framework contemplates that the NSFR will be subject to an observation period through mid-2016 and, subject to any revisions resulting from the analyses conducted and data collected during the observation period, implemented as a minimum standard by January 1, 2018. These new standards are subject to further rulemaking and their terms could change before implementation.

Imposition of Liability for Undercapitalized Subsidiaries. Bank regulators are required to take “prompt corrective action” to resolve problems associated with insured depository institutions whose capital declines

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below certain levels. In the event an institution becomes “undercapitalized,” it must submit a capital restoration plan. The capital restoration plan will not be accepted by the regulators unless each company having control of the undercapitalized institution guarantees the subsidiary’s compliance with the capital restoration plan up to a certain specified amount. Any such guarantee from a depository institution’s holding company is entitled to a priority of payment in bankruptcy.

The aggregate liability of the holding company of an undercapitalized bank is limited to the lesser of 5% of the institution’s assets at the time it became undercapitalized or the amount necessary to cause the institution to be “adequately capitalized.” The bank regulators have greater power in situations where an institution becomes “significantly” or “critically” undercapitalized or fails to submit a capital restoration plan. For example, a bank holding company controlling such an institution can be required to obtain prior Federal Reserve Board approval of proposed dividends, or might be required to consent to a consolidation or to divest the troubled institution or other affiliates.

Acquisitions by Bank Holding Companies. The BHCA requires every bank holding company to obtain the prior approval of the Federal Reserve Board before it may acquire all or substantially all of the assets of any bank, or ownership or control of any voting shares of any bank, if after such acquisition it would own or control, directly or indirectly, more than 5% of the voting shares of such bank. In approving bank acquisitions by bank holding companies, the Federal Reserve Board is required to consider, among other things, the financial and managerial resources and future prospects of the bank holding company and the banks concerned, the convenience and needs of the communities to be served and various competitive factors.

Control Acquisitions. The Change in Bank Control Act (“CBCA”) prohibits a person or group of persons from acquiring “control” of a bank holding company unless the Federal Reserve Board has been notified and has not objected to the transaction. Under a rebuttable presumption established by the Federal Reserve Board, the acquisition of 10% or more of a class of voting stock of a bank holding company with a class of securities registered under Section 12 of the Exchange Act, such as the Company, would, under the circumstances set forth in the presumption, constitute acquisition of control of the Company.

In addition, the CBCA prohibits any entity from acquiring 25% (5% in the case of an acquiror that is a bank holding company) or more of a bank holding company’s or bank’s voting securities, or otherwise obtaining control or a controlling influence over a bank holding company or bank without the approval of the Federal Reserve Board. In most circumstances, an entity that owns 25% or more of the voting securities of a banking organization owns enough of the capital resources to have a controlling influence over such banking organization for purposes of the CBCA. On September 22, 2008, the Federal Reserve Board issued a policy statement on equity investments in bank holding companies and banks, which allows the Federal Reserve Board to generally be able to conclude that an entity’s investment is not “controlling” if the entity does not own in excess of 15% of the voting power and 33% of the total equity of the bank holding company or bank. Depending on the nature of the overall investment and the capital structure of the banking organization, the Federal Reserve Board will permit, based on the policy statement, noncontrolling investments in the form of voting and nonvoting shares that represent in the aggregate (i) less than one-third of the total equity of the banking organization (and less than one-third of any class of voting securities, assuming conversion of all convertible nonvoting securities held by the entity) and (ii) less than 15% of any class of voting securities of the banking organization.

The Bank

The Bank is a Texas-chartered banking association, the deposits of which are insured by the DIF of the FDIC. The Bank is not a member of the Federal Reserve System; therefore, the Bank is subject to supervision and regulation by the FDIC and the Texas Department of Banking. Such supervision and regulation subject the Bank to special restrictions, requirements, potential enforcement actions and periodic examination by the FDIC and the Texas Department of Banking. Because the Federal Reserve Board regulates the Company, the Federal Reserve Board also has supervisory authority which directly affects the Bank. Further, because the Bank had

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total assets of over $10 billion as of December 31, 2012, the Bank will be subject to supervision and regulation by the Consumer Financial Protection Bureau (“CFPB”). The CFPB is responsible for implementing, examining and enforcing compliance with federal consumer protection laws.

Equivalence to National Bank Powers. The Texas Constitution, as amended in 1986, provides that a Texas-chartered bank has the same rights and privileges that are or may be granted to national banks domiciled in Texas. To the extent that the Texas laws and regulations may have allowed state-chartered banks to engage in a broader range of activities than national banks, the FDICIA has operated to limit this authority. FDICIA provides that no state bank or subsidiary thereof may engage as principal in any activity not permitted for national banks, unless the institution complies with applicable capital requirements and the FDIC determines that the activity poses no significant risk to the DIF. In general, statutory restrictions on the activities of banks are aimed at protecting the safety and soundness of depository institutions.

Financial Modernization. Under the Gramm-Leach-Bliley Act, a national bank may establish a financial subsidiary and engage, subject to limitations on investment, in activities that are financial in nature, other than insurance underwriting as principal, insurance company portfolio investment, real estate development, real estate investment, annuity issuance and merchant banking activities. To do so, a bank must be well capitalized, well managed and have a CRA rating of satisfactory or better. Subsidiary banks of a financial holding company or national banks with financial subsidiaries must remain well capitalized and well managed in order to continue to engage in activities that are financial in nature without regulatory actions or restrictions, which could include divestiture of the financial in nature subsidiary or subsidiaries. In addition, a financial holding company or a bank may not acquire a company that is engaged in activities that are financial in nature unless each of the subsidiary banks of the financial holding company or the bank has a CRA rating of satisfactory or better.

Although the powers of state chartered banks are not specifically addressed in the Gramm-Leach-Bliley Act, Texas-chartered banks such as the Bank, will have the same if not greater powers as national banks through the parity provision contained in the Texas Constitution.

Branching. Pursuant to the Dodd-Frank Act, banks are permitted to engage in de novo interstate branching if the laws of the state where the new branch is to be established would permit the establishment of the branch if it were chartered by such state, subject to applicable regulatory review and approval requirements. The Dodd-Frank Act also created certain regulatory requirements for interstate mergers and acquisitions, including that the acquiring bank must be well capitalized and well managed. Texas law provides that a Texas-chartered bank can establish a branch anywhere in Texas provided that the branch is approved in advance by the Texas Department of Banking. The branch must also be approved by the FDIC, which considers a number of factors, including financial history, capital adequacy, earnings prospects, character of management, needs of the community and consistency with corporate powers.

Restrictions on Transactions with Affiliates and Insiders. Transactions between the Bank and its nonbanking affiliates, including the Company, are subject to Section 23A of the Federal Reserve Act. In general, Section 23A imposes limits on the amount of such transactions to 10% of the Bank’s capital stock and surplus and requires that such transactions be secured by designated amounts of specified collateral. It also limits the amount of advances to third parties which are collateralized by the securities or obligations of the Company or its subsidiaries. The Dodd-Frank Act significantly expanded the coverage and scope of the limitations on affiliate transactions within a banking organization.

Affiliate transactions are also subject to Section 23B of the Federal Reserve Act which generally requires that certain transactions between the Bank and its affiliates be on terms substantially the same, or at least as favorable to the Bank, as those prevailing at the time for comparable transactions with or involving other nonaffiliated persons. The Federal Reserve Board has also issued Regulation W which codifies prior regulations under Sections 23A and 23B of the Federal Reserve Act and interpretive guidance with respect to affiliate transactions.

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The restrictions on loans to directors, executive officers, principal shareholders and their related interests (collectively referred to herein as “insiders”) contained in the Federal Reserve Act and Regulation O apply to all insured institutions and their subsidiaries and holding companies. Insiders are subject to enforcement actions for knowingly accepting loans in violation of applicable restrictions.

Restrictions on Distribution of Subsidiary Bank Dividends and Assets. Dividends paid by the Bank have provided a substantial part of the Company’s operating funds and for the foreseeable future it is anticipated that dividends paid by the Bank to the Company will continue to be the Company’s principal source of operating funds. Capital adequacy requirements serve to limit the amount of dividends that may be paid by the Bank. Under federal law, the Bank cannot pay a dividend if, after paying the dividend, the Bank will be “undercapitalized.” The FDIC may declare a dividend payment to be unsafe and unsound even though the Bank would continue to meet its capital requirements after the dividend. Because the Company is a legal entity separate and distinct from its subsidiaries, its right to participate in the distribution of assets of any subsidiary upon the subsidiary’s liquidation or reorganization will be subject to the prior claims of the subsidiary’s creditors. In the event of a liquidation or other resolution of an insured depository institution, the claims of depositors and other general or subordinated creditors are entitled to a priority of payment over the claims of holders of any obligation of the institution to its shareholders, including any depository institution holding company (such as the Company) or any shareholder or creditor thereof.

Consumer Financial Protection Bureau. The Dodd-Frank Act established the CFPB, which has supervisory authority over depository institutions with total assets of $10 billion or greater. The CFPB will focus its supervision and regulatory efforts on (i) risks to consumers and compliance with the federal consumer financial laws, when it evaluates the policies and practices of a financial institution; (ii) the markets in which firms operate and risks to consumers posed by activities in those markets; (iii) depository institutions that offer a wide variety of consumer financial products and services; depository institutions with a more specialized focus; and (iv) non-depository companies that offer one or more consumer financial products or services.

Examinations. The FDIC periodically examines and evaluates state non-member banks. The Texas Department of Banking also conducts examinations of state banks, but may accept the results of a federal examination in lieu of conducting an independent examination. In addition, the FDIC and Texas Department of Banking may elect to conduct a joint examination. Further, because the Bank has total assets of over $10 billion as of December 31, 2012, the CFPB has examination authority with respect to the Bank’s compliance with federal consumer protection laws. Compliance with consumer protection laws will be considered when banking regulators are asked to approve a proposed transaction.

Capital Adequacy Requirements. The FDIC has adopted regulations establishing minimum requirements for the capital adequacy of insured institutions. The FDIC may establish higher minimum requirements if, for example, a bank has previously received special attention or has a high susceptibility to interest rate risk. When final rules for the Basel III framework are adopted, the current capital adequacy requirements are expected to change as described above in “Proposed Capital Adequacy Requirements.”

The FDIC’s risk-based capital guidelines generally require state banks to have a minimum ratio of Tier 1 capital to total risk-weighted assets of 4.0% and a ratio of total capital to total risk-weighted assets of 8.0%. The capital categories have the same definitions for the Bank as for the Company. As of December 31, 2012, the Bank’s ratio of Tier 1 capital to total risk-weighted assets was 14.19% and its ratio of total capital to total risk-weighted assets was 15.01%.

The FDIC’s leverage guidelines require state banks to maintain Tier 1 capital of no less than 4.0% of average total assets, except in the case of certain highly rated banks for which the requirement is 3.0% of average total assets. The Texas Department of Banking has issued a policy which generally requires state chartered banks to maintain a leverage ratio (defined in accordance with federal capital guidelines) of 5.0%. As of December 31, 2012, the Bank’s ratio of Tier 1 capital to average total assets (leverage ratio) was 6.99%.

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Corrective Measures for Capital Deficiencies. The federal banking regulators are required to take “prompt corrective action” with respect to capital-deficient institutions. Agency regulations define, for each capital category, the levels at which institutions are “well-capitalized,” “adequately capitalized,” “under capitalized,” “significantly under capitalized” and “critically under capitalized.” A “well-capitalized” bank has a total risk-based capital ratio of 10.0% or higher; a Tier 1 risk-based capital ratio of 6.0% or higher; a leverage ratio of 5.0% or higher; and is not subject to any written agreement, order or directive requiring it to maintain a specific capital level for any capital measure. An “adequately capitalized” bank has a total risk-based capital ratio of 8.0% or higher; a Tier 1 risk-based capital ratio of 4.0% or higher; a leverage ratio of 4.0% or higher (3.0% or higher if the bank was rated a composite 1 in its most recent examination report and is not experiencing significant growth); and does not meet the criteria for a well capitalized bank. A bank is “under capitalized” if it fails to meet any one of the ratios required to be adequately capitalized. At December 31, 2012, the Bank was classified as “well-capitalized” for purposes of the FDIC’s prompt corrective action regulations.

In addition to requiring undercapitalized institutions to submit a capital restoration plan, agency regulations contain broad restrictions on certain activities of undercapitalized institutions including asset growth, acquisitions, branch establishment and expansion into new lines of business. With certain exceptions, an insured depository institution is prohibited from making capital distributions, including dividends, and is prohibited from paying management fees to control persons if the institution would be undercapitalized after any such distribution or payment.

As an institution’s capital decreases, the FDIC’s enforcement powers become more severe. A significantly undercapitalized institution is subject to mandated capital raising activities, restrictions on interest rates paid and transactions with affiliates, removal of management and other restrictions. The FDIC has only very limited discretion in dealing with a critically undercapitalized institution and is virtually required to appoint a receiver or conservator.

Banks with risk-based capital and leverage ratios below the required minimums may also be subject to certain administrative actions, including the termination of deposit insurance upon notice and hearing, or a temporary suspension of insurance without a hearing in the event the institution has no tangible capital.

Deposit Insurance Assessments. Substantially all of the deposits of the Bank are insured up to applicable limits (currently $250,000) by the DIF of the FDIC and the Bank must pay deposit insurance assessments to the FDIC for such deposit insurance protection. The FDIC maintains the DIF by designating a required reserve ratio. If the reserve ratio falls below the designated level, the FDIC must adopt a restoration plan that provides that the DIF will return to an acceptable level generally within five years. The designated reserve ratio is currently set at 2.00%. The FDIC has the discretion to price deposit insurance according to the risk for all insured institutions regardless of the level of the reserve ratio.

The DIF reserve ratio is maintained by assessing depository institutions an insurance premium based upon certain statutory factors. Under its current regulations, the FDIC imposes assessments for deposit insurance according to a depository institution’s ranking in one of four risk categories based upon supervisory and capital evaluations. The assessment rate for an individual institution is determined according to a formula based on a combination of weighted average CAMELS component ratings, financial ratios and, for institutions that have long-term debt ratings, the average ratings of its long-term debt. On February 7, 2011, the FDIC approved a final rule that amended the then-existing DIF restoration plan and implemented certain provisions of the Dodd-Frank Act. As of April 1, 2011 the assessment base is determined using average consolidated total assets minus average tangible equity rather than the current assessment base of adjusted domestic deposits. Since the change resulted in a much larger assessment base, the final rule also lowered the assessment rates in order to keep the total amount collected from financial institutions relatively unchanged from the amounts previously collected.

For large institutions (generally those with total assets of $10 billion or more), such as the Bank, the initial base assessment rate ranges from 5 to 35 basis points on an annualized basis. After the effect of potential base-rate adjustments, the total base assessment rate could range from 2.5 to 45 basis points on an annualized basis.

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Assessment rates for large institutions are calculated using a scorecard that combines CAMELS ratings and certain forward-looking financial measures to assess the risk a large institution poses to the DIF.

In November 2009, the FDIC adopted a rule that required all insured institutions, with limited exceptions, to prepay their estimated quarterly risk-based assessments for the fourth quarter of 2009 and for all of 2010, 2011 and 2012. As of December 31, 2012, $16.7 million in pre-paid deposit insurance was included in other assets in the Company’s consolidated balance sheet.

Concentrated Commercial Real Estate Lending Regulations. The federal banking agencies, including the FDIC, have promulgated guidance governing financial institutions with concentrations in commercial real estate lending. The guidance provides that a bank has a concentration in commercial real estate lending if (i) total reported loans for construction, land development, and other land represent 100% or more of total capital or (ii) total reported loans secured by multifamily and non-farm residential properties and loans for construction, land development, and other land represent 300% or more of total capital and the bank’s commercial real estate loan portfolio has increased 50% or more during the prior 36 months. Owner occupied loans are excluded from this second category. If a concentration is present, management must employ heightened risk management practices that address the following key elements: including board and management oversight and strategic planning, portfolio management, development of underwriting standards, risk assessment and monitoring through market analysis and stress testing, and maintenance of increased capital levels as needed to support the level of commercial real estate lending.

Community Reinvestment Act. The CRA and the regulations issued thereunder are intended to encourage banks to help meet the credit needs of their service area, including low and moderate income neighborhoods, consistent with the safe and sound operations of the banks. These regulations also provide for regulatory assessment of a bank’s record in meeting the needs of its service area when considering applications to establish branches, merger applications and applications to acquire the assets and assume the liabilities of another bank. FIRREA requires federal banking agencies to make public a rating of a bank’s performance under the CRA. In the case of a bank holding company, the CRA performance record of the banks involved in the transaction are reviewed in connection with the filing of an application to acquire ownership or control of shares or assets of a bank or to merge with any other bank holding company. An unsatisfactory record can substantially delay or block the transaction.

Anti-Money Laundering and Anti-Terrorism Legislation. A major focus of governmental policy on financial institutions in recent years has been aimed at combating money laundering and terrorist financing. The USA PATRIOT Act of 2001 (the “USA Patriot Act”) substantially broadened the scope of United States anti-money laundering laws and regulations by imposing significant new compliance and due diligence obligations, creating new crimes and penalties and expanding the extra-territorial jurisdiction of the United States. The United States Treasury Department has issued and, in some cases, proposed a number of regulations that apply various requirements of the USA Patriot Act to financial institutions. These regulations impose obligations on financial institutions to maintain appropriate policies, procedures and controls to detect, prevent and report money laundering and terrorist financing and to verify the identity of their customers. Certain of those regulations impose specific due diligence requirements on financial institutions that maintain correspondent or private banking relationships with non-U.S. financial institutions or persons. Failure of a financial institution to maintain and implement adequate programs to combat money laundering and terrorist financing, or to comply with all of the relevant laws or regulations, could have serious legal and reputational consequences for the institution.

Office of Foreign Assets Control Regulation. The United States has imposed economic sanctions that affect transactions with designated foreign countries, nationals and others. These are typically known as the “OFAC” rules based on their administration by the U.S. Treasury Department Office of Foreign Assets Control (“OFAC”). The OFAC-administered sanctions targeting countries take many different forms. Generally, however, they contain one or more of the following elements: (i) restrictions on trade with or investment in a sanctioned country, including prohibitions against direct or indirect imports from and exports to a sanctioned country and

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prohibitions on “U.S. persons” engaging in financial transactions relating to making investments in, or providing investment-related advice or assistance to, a sanctioned country; and (ii) a blocking of assets in which the government or specially designated nationals of the sanctioned country have an interest, by prohibiting transfers of property subject to U.S. jurisdiction (including property in the possession or control of U.S. persons). Blocked assets (e.g., property and bank deposits) cannot be paid out, withdrawn, set off or transferred in any manner without a license from OFAC. Failure to comply with these sanctions could have serious legal and reputational consequences.

Privacy. In addition to expanding the activities in which banks and bank holding companies may engage, the Gramm-Leach-Bliley Act also imposed new requirements on financial institutions with respect to customer privacy. The Gramm-Leach-Bliley Act generally prohibits disclosure of customer information to non-affiliated third parties unless the customer has been given the opportunity to object and has not objected to such disclosure. Financial institutions are further required to disclose their privacy policies to customers annually. Financial institutions, however, will be required to comply with state law if it is more protective of customer privacy than the Gramm-Leach-Bliley Act.

Incentive Compensation. In June 2010, the Federal Reserve Board, OCC and FDIC issued comprehensive final guidance on incentive compensation policies intended to ensure that the incentive compensation policies of banking organizations do not undermine the safety and soundness of such organizations by encouraging excessive risk-taking. The guidance, which covers all employees that have the ability to materially affect the risk profile of an organization, either individually or as part of a group, is based upon the key principles that a banking organization’s incentive compensation arrangements should (i) provide incentives that do not encourage risk-taking beyond the organization’s ability to effectively identify and manage risks, (ii) be compatible with effective internal controls and risk management, and (iii) be supported by strong corporate governance, including active and effective oversight by the organization’s board of directors

The Federal Reserve Board will review, as part of the regular, risk-focused examination process, the incentive compensation arrangements of banking organizations, such as the Company, that are not “large, complex banking organizations.” These reviews will be tailored to each organization based on the scope and complexity of the organization’s activities and the prevalence of incentive compensation arrangements. The findings of the supervisory initiatives will be included in reports of examination. Deficiencies will be incorporated into the organization’s supervisory ratings, which can affect the organization’s ability to make acquisitions and take other actions. Enforcement actions may be taken against a banking organization if its incentive compensation arrangements, or related risk-management control or governance processes, pose a risk to the organization’s safety and soundness and the organization is not taking prompt and effective measures to correct the deficiencies.

Legislative and Regulatory Initiatives

From time to time, various legislative and regulatory initiatives are introduced in Congress and state legislatures, as well as by regulatory agencies. Such initiatives may include proposals to expand or contract the powers of bank holding companies and depository institutions or proposals to substantially change the financial institution regulatory system. Such legislation could change banking statutes and the operating environment of the Company in substantial and unpredictable ways. If enacted, such legislation could increase or decrease the cost of doing business, limit or expand permissible activities or affect the competitive balance among banks, savings associations, credit unions, and other financial institutions. The Company cannot predict whether any such legislation will be enacted, and, if enacted, the effect that it, or any implementing regulations, would have on the financial condition or results of operations of the Company. A change in statutes, regulations or regulatory policies applicable to the Company or the Bank could have a material effect on the Company’s business, financial condition and results of operations.

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Dodd-Frank Act

The Dodd-Frank Act, enacted in July 2010, significantly restructured the financial regulatory landscape in the United States. It contains numerous provisions that affect all bank holding companies and banks. Many of the Dodd-Frank Act’s provisions are still subject to the final rulemaking by federal banking agencies, and the implication of the Dodd-Frank Act for the Company’s business will depend to a large extent on how such rules are adopted and implemented. The Company’s management continues to review actively the provisions of the Dodd–Frank Act and assess its probable impact on its business, financial condition, and results of operations.

The Dodd-Frank Act authorized the Federal Reserve Board to adopt enhanced supervision and prudential standards for, among others, bank holding companies with total consolidated assets of $50 billion or more (often referred to as “systemically important financial institutions” or “SIFI”), and authorized the Federal Reserve Board to establish such standards either on its own or upon the recommendations of the Financial Stability Oversight Council, a new systemic risk oversight body created by the Dodd-Frank Act. Most of the Proposed SIFI Rules will not apply to the Company as its total consolidated assets remain below $50 billion. However, two aspects of the Proposed SIFI Rules apply to bank holding companies with total consolidated assets of $10 billion or more: (a) requirements for annual stress testing of capital under one base and two stress scenarios and (b) certain corporate governance provisions requiring, among other things, that each bank holding company establish a risk committee of its board of directors and that that committee include a “risk expert.”

Effect on Economic Environment

The policies of regulatory authorities, including the monetary policy of the Federal Reserve Board, have a significant effect on the operating results of bank holding companies and their subsidiaries. Among the means available to the Federal Reserve Board to affect the money supply are open market operations in U.S. government securities, changes in the discount rate on member bank borrowings, and changes in reserve requirements against member bank deposits. These means are used in varying combinations to influence overall growth and distribution of bank loans, investments and deposits, and their use may affect interest rates charged on loans or paid for deposits.

Federal Reserve Board monetary policies have materially affected the operating results of commercial banks in the past and are expected to continue to do so in the future. The nature of future monetary policies and the effect of such policies on the business and earnings of the Company and its subsidiaries cannot be predicted.

An investment in the Company’s common stock involves risks. The following is a description of the material risks and uncertainties that the Company believes affect its business and an investment in the common stock. Additional risks and uncertainties that the Company is unaware of, or that it currently deems immaterial, also may become important factors that affect the Company and its business. If any of the risks described in this Annual Report on Form 10-K were to occur, the Company’s financial condition, results of operations and cash flows could be materially and adversely affected. If this were to happen, the value of the common stock could decline significantly and you could lose all or part of your investment.

Risks Associated with the Company’s Business

If the Company is not able to continue its historical levels of growth, it may not be able to maintain its historical earnings trends.

To achieve its past levels of growth, the Company has focused on both internal growth and acquisitions. The Company may not be able to sustain its historical rate of growth or may not be able to grow at all. More specifically, the Company may not be able to obtain the financing necessary to fund additional growth and may

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not be able to find suitable acquisition candidates. Various factors, such as economic conditions and competition, may impede or prohibit the opening of new banking centers and the completion of acquisitions. Further, the Company may be unable to attract and retain experienced bankers, which could adversely affect its internal growth. If the Company is not able to continue its historical levels of growth, it may not be able to maintain its historical earnings trends.

If the Company is unable to manage its growth effectively, its operations could be negatively affected.

Companies that experience rapid growth face various risks and difficulties, including:

In addition, in order to manage its growth and maintain adequate information and reporting systems within its organization, the Company must identify, hire and retain additional qualified associates, particularly in the accounting and operational areas of its business.

If the Company does not manage its growth effectively, its business, financial condition, results of operations and future prospects could be negatively affected, and the Company may not be able to continue to implement its business strategy and successfully conduct its operations.

Difficult market conditions and economic trends have adversely affected the banking industry and could adversely affect the Company’s business, financial condition, results of operations and cash flows.

The Company is operating in a challenging and uncertain economic environment, including generally uncertain conditions nationally and locally in its markets. Although economic conditions have improved in the last year, financial institutions continue to be affected by declines in the real estate market and uncertain conditions.

The Company’s ability to assess the creditworthiness of customers and to estimate the losses inherent in its loan portfolio is made more complex by these uncertain market and economic conditions. A prolonged national economic recession or further deterioration of these conditions in the Company’s markets could drive losses beyond that which is provided for in its allowance for credit losses and result in the following consequences:

While economic conditions in the State of Texas and the U.S. are showing signs of recovery, there can be no assurance that these difficult conditions will continue to improve. Continued declines in real estate values, home sales volumes and financial stress on borrowers as a result of the uncertain economic environment, including job losses, could have an adverse effect on the Company’s borrowers or their customers, which could adversely affect the Company’s business, financial condition, results of operations and cash flows.

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The Company’s business is subject to interest rate risk and fluctuations in interest rates may adversely affect its financial condition and results of operations.

The majority of the Company’s assets are monetary in nature and, as a result, the Company is subject to significant risk from changes in interest rates. Changes in interest rates can impact the Company’s net interest income as well as the valuation of its assets and liabilities. The Company’s earnings are significantly dependent on its net interest income. Net interest income is the difference between the interest income earned on loans, investments and other interest-earning assets and the interest expense paid on deposits, borrowings and other interest-bearing liabilities.

Changes in monetary policy, including changes in interest rates, could influence the interest the Company receives on loans and securities and the amount of interest it pays on deposits and borrowings, and could also affect (i) the Company’s ability to originate loans and obtain deposits, (ii) the fair value of the Company’s financial assets and liabilities and (iii) the average duration of the Company’s mortgage-backed securities portfolio. If the interest rates paid on deposits and other borrowings increase at a faster rate than the interest rates received on loans and other investments, the Company’s net interest income, and therefore earnings, could be adversely affected. Earnings could also be adversely affected if the interest rates received on loans and other investments decrease more quickly than the interest rates paid on deposits and other borrowings. Further, the Company’s assets and liabilities may react differently to changes in overall market rates or conditions because there may be mismatches between the repricing or maturity characteristics of the assets and liabilities. Any substantial, unexpected, prolonged change in market interest rates could have a material adverse effect on the Company’s business, financial condition and results of operations.

If the Company is unable to identify and acquire other financial institutions and successfully integrate its acquired businesses, its business and earnings may be negatively affected.

The market for acquisitions remains highly competitive, and the Company may be unable to find acquisition candidates in the future that fit its acquisition and growth strategy. To the extent that the Company is unable to find suitable acquisition candidates, an important component of its growth strategy may be lost.

Acquisitions of financial institutions involve operational risks and uncertainties and acquired companies may have unforeseen liabilities, exposure to asset quality problems, key employee and customer retention problems and other problems that could negatively affect the Company’s organization. The Company may not be able to complete future acquisitions and, if completed, the Company may not be able to successfully integrate the operations, management, products and services of the entities that it acquires and eliminate redundancies. The integration process could result in the loss of key employees or disruption of the combined entity’s ongoing business or inconsistencies in standards, controls, procedures and policies that adversely affect the Company’s ability to maintain relationships with customers and employees or achieve the anticipated benefits of the transaction. The integration process may also require significant time and attention from the Company’s management that they would otherwise direct at servicing existing business and developing new business. The Company’s inability to find suitable acquisition candidates and failure to successfully integrate the entities it acquires into its existing operations may increase its operating costs significantly and adversely affect its business and earnings.

The Company’s dependence on loans secured by real estate subjects it to risks relating to fluctuations in the real estate market that could adversely affect its financial condition, results of operations and cash flows.

Approximately 81.0% of the Company’s total loans as of December 31, 2012 consisted of loans included in the real estate loan portfolio, with 10.6% in construction and land development, 27.8% in residential real estate and 42.6% in commercial real estate (includes farmland and multifamily residential). The real estate collateral in each case provides an alternate source of repayment in the event of default by the borrower and may deteriorate in value during the time the credit is extended. A weakening of the real estate market in the Company’s primary market areas could have an adverse effect on the demand for new loans, the ability of borrowers to repay

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outstanding loans, the value of real estate and other collateral securing the loans and the value of real estate owned by the Company. If real estate values decline, it is also more likely that the Company would be required to increase its allowance for credit losses, which could adversely affect its financial condition, results of operations and cash flows.

The Company’s commercial real estate and commercial loans expose it to increased credit risks, and these risks will increase if the Company succeeds in increasing these types of loans.

The Company, while maintaining its conservative approach to lending, has emphasized both new and existing loan products, focusing on managing its commercial real estate and commercial loan portfolios, and intends to continue to increase its lending activities and acquire loans in possible future acquisitions. As a result, commercial real estate and commercial loans as a proportion of its portfolio could increase. As of December 31, 2012, commercial real estate (includes farmland and multifamily residential) and commercial loans totaled $2.97 billion. In general, commercial real estate loans and commercial loans yield higher returns and often generate a deposit relationship, but also pose greater credit risks than do owner-occupied residential real estate loans. These types of loans are also typically larger than residential real estate loans. Accordingly, the deterioration of one or several of these loans could cause a significant increase in nonperforming loans, which could result in a loss of earnings from these loans and an increase in the provision for credit losses and net charge-offs.

The Company makes both secured and some unsecured commercial loans. Unsecured loans generally involve a higher degree of risk of loss than do secured loans because, without collateral, repayment is wholly dependent upon the success of the borrowers’ businesses. Secured commercial loans are generally collateralized by accounts receivable, inventory, equipment or other assets owned by the borrower and include a personal guaranty of the business owner. Compared to real estate, that type of collateral is more difficult to monitor, its value is harder to ascertain, it may depreciate more rapidly and it may not be as readily saleable if repossessed. Further, commercial loans generally will be serviced primarily from the operation of the business, which may not be successful, while commercial real estate loans generally will be serviced from income on the properties securing the loans. As the Company’s various commercial loan portfolios increase, the corresponding risks and potential for losses from these loans will also increase.

The Company’s profitability depends significantly on local economic conditions.

The Company’s success depends primarily on the general economic conditions of the primary markets in Texas in which it operates and where its loans are concentrated. In addition, the pending acquisition of Coppermark Bancshares, Inc. will expand the Company’s market area to Oklahoma and the Company’s success will also be impacted by general economic conditions in Oklahoma. The local economic conditions in Texas have a significant impact on the Company’s commercial, real estate and construction and land development loans, the ability of its borrowers to repay their loans and the value of the collateral securing these loans. Accordingly, if the population or income growth in the Company’s market areas is slower than projected, income levels, deposits and housing starts could be adversely affected and could result in a reduction of the Company’s expansion, growth and profitability. Although economic conditions in Texas have not deteriorated to the same extent as in other areas of the country, such conditions could decline further. If the Company’s market areas experience a downturn or a recession for a prolonged period of time, the Company could experience significant increases in nonperforming loans, which could lead to operating losses, impaired liquidity and eroding capital. A significant decline in general economic conditions, caused by inflation, recession, acts of terrorism, outbreaks of hostilities or other international or domestic calamities, unemployment or other factors could impact these local economic conditions and could negatively affect the Company’s financial condition, results of operations and cash flows.

The Company’s allowance for credit losses may not be sufficient to cover actual credit losses, which could adversely affect its earnings.

As a lender, the Company is exposed to the risk that its loan customers may not repay their loans according to the terms of these loans and the collateral securing the payment of these loans may be insufficient to fully

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compensate the Company for the outstanding balance of the loan plus the costs to dispose of the collateral. The Company maintains an allowance for credit losses in an attempt to cover estimated losses inherent in its loan portfolio. Additional credit losses will likely occur in the future and may occur at a rate greater than the Company has experienced to date. The determination of the appropriate level of the allowance inherently involves a high degree of subjectivity and requires the Company to make significant estimates of current credit risks, future trends and general economic conditions, all of which may undergo material changes. If the Company’s assumptions prove to be incorrect or if it experiences significant loan losses in future periods, its current allowance may not be sufficient to cover actual loan losses and adjustments may be necessary to allow for different economic conditions or adverse developments in its loan portfolio. A material addition to the allowance could cause net income, and possibly capital, to decrease.

In addition, federal and state regulators periodically review the Company’s allowance for credit losses and may require the Company to increase its provision for credit losses or recognize further charge-offs, based on judgments different than those of the Company’s management. An increase in the Company’s allowance for credit losses or charge-offs as required by these regulatory agencies could have a material adverse effect on the Company’s operating results and financial condition.

The small to medium-sized businesses that the Company lends to may have fewer resources to weather a downturn in the economy, which could materially harm the Company’s operating results.

The Company makes loans to privately-owned businesses, many of which are considered to be small to medium-sized businesses. Small to medium-sized businesses frequently have smaller market share than their competition, may be more vulnerable to economic downturns, often need substantial additional capital to expand or compete and may experience significant volatility in operating results. Any one or more of these factors may impair the borrower’s ability to repay a loan. In addition, the success of a small to medium-sized business often depends on the management talents and efforts of one or two persons or a small group of persons, and the death, disability or resignation of one or more of these persons could have a material adverse impact on the business and its ability to repay a loan. Economic downturns and other events that negatively impact the Company’s market areas could cause the Company to incur substantial credit losses that could negatively affect the Company’s results of operations and financial condition.

Liquidity risk could impair the Company’s ability to fund operations and jeopardize its financial condition.

Liquidity is essential to the Company’s business. An inability to raise funds through deposits, borrowings, the sale of loans and other sources could have a substantial negative effect on its liquidity. The Company’s access to funding sources in amounts adequate to finance its activities or on terms which are acceptable to it could be impaired by factors that affect the Company specifically or the financial services industry or economy in general. Factors that could detrimentally impact the Company’s access to liquidity sources include a decrease in the level of its business activity as a result of a downturn in the markets in which its loans are concentrated or adverse regulatory action against it. The Company’s ability to borrow could also be impaired by factors that are not specific to it, such as a disruption in the financial markets or negative views and expectations about the prospects for the financial services industry in light of the recent turmoil faced by banking organizations and the continued deterioration in credit markets.

If the goodwill that the Company recorded in connection with a business acquisition becomes impaired, it could require charges to earnings.

Goodwill represents the amount by which the acquisition cost exceeds the fair value of net assets the Company acquired in the purchase of another financial institution. The Company reviews goodwill for impairment at least annually, or more frequently if events or changes in circumstances indicate the carrying value of the asset might be impaired.

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The Company determines impairment by comparing the implied fair value of the reporting unit goodwill with the carrying amount of that goodwill. If the carrying amount of the reporting unit goodwill exceeds the implied fair value of that goodwill, an impairment loss is recognized in an amount equal to that excess. Any such adjustments are reflected in the Company’s results of operations in the periods in which they become known. At December 31, 2012, the Company’s goodwill totaled $1.22 billion. While the Company has not recorded any such impairment charges since it initially recorded the goodwill, there can be no assurance that the Company’s future evaluations of goodwill will not result in findings of impairment and related write-downs, which may have a material adverse effect on its financial condition and results of operations.

The Company’s accounting estimates and risk management processes rely on analytical and forecasting models.

The processes the Company uses to estimate its probable credit losses and to measure the fair value of financial instruments, as well as the processes used to estimate the effects of changing interest rates and other market measures on the Company’s financial condition and results of operations, depends upon the use of analytical and forecasting models. These models reflect assumptions that may not be accurate, particularly in times of market stress or other unforeseen circumstances. Even if these assumptions are accurate, the models may prove to be inadequate or inaccurate because of other flaws in their design or their implementation.

If the models the Company uses for interest rate risk and asset-liability management are inadequate, the Company may incur increased or unexpected losses upon changes in market interest rates or other market measures. If the models the Company uses for determining its probable credit losses are inadequate, the allowance for credit losses may not be sufficient to support future charge-offs. If the models the Company uses to measure the fair value of financial instruments is inadequate, the fair value of such financial instruments may fluctuate unexpectedly or may not accurately reflect what the Company could realize upon sale or settlement of such financial instruments. Any such failure in the Company’s analytical or forecasting models could have a material adverse effect on the Company’s business, financial condition and results of operations.

The Company may be adversely affected by the soundness of other financial institutions.

Financial services institutions are interrelated as a result of trading, clearing, counterparty, or other relationships. The Company has exposure to many different industries and counterparties, and routinely executes transactions with counterparties in the financial services industry, including commercial banks, brokers and dealers, investment banks, and other institutional clients. Many of these transactions expose the Company to credit risk in the event of a default by a counterparty or client. In addition, the Company’s credit risk may be exacerbated when the collateral held by the Company cannot be realized upon or is liquidated at prices not sufficient to recover the full amount of the credit or derivative exposure due to the Company. Any such losses could have a material adverse effect on the Company’s financial condition, results of operations and cash flows.

The Company may need to raise additional capital in the future and such capital may not be available when needed or at all.

The Company may need to raise additional capital in the future to provide it with sufficient capital resources and liquidity to meet its commitments and business needs. In addition, the Company may elect to raise additional capital to support its business or to finance acquisitions, if any. The Company’s ability to raise additional capital, if needed, will depend on, among other things, conditions in the capital markets at that time, which are outside of its control, and its financial performance.

The Company cannot assure you that such capital will be available to it on acceptable terms or at all. Any occurrence that may limit its access to the capital markets, such as a decline in the confidence of investors, depositors of Prosperity Bank or counterparties participating in the capital markets, may adversely affect the Company’s capital costs and its ability to raise capital and, in turn, its liquidity. Moreover, if the Company needs

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to raise capital in the future, it may have to do so when many other financial institutions are also seeking to raise capital and would have to compete with those institutions for investors. An inability to raise additional capital on acceptable terms when needed could have a material adverse effect on the Company’s business, financial condition and results of operations.

New lines of business or new products and services may subject the Company to additional risks.

From time to time, the Company may implement or may acquire new lines of business or offer new products and services within existing lines of business. There are substantial risks and uncertainties associated with these efforts, particularly in instances where the markets are not fully developed. In developing and marketing new lines of business and/or new products and services, the Company may invest significant time and resources. Initial timetables for the introduction and development of new lines of business and/or new products or services may not be achieved and price and profitability targets may not prove feasible. External factors, such as compliance with regulations, competitive alternatives and shifting market preferences, may also impact the successful implementation of a new line of business or a new product or service. Furthermore, any new line of business and/or new product or service could have a significant impact on the effectiveness of the Company’s system of internal controls. Failure to successfully manage these risks in the development and implementation of new lines of business or new products or services could have a material adverse effect on the Company’s business, financial condition and results of operations.

An interruption in or breach in security of the Company’s information systems may result in a loss of customer business and have an adverse effect on the Company’s results of operations, financial condition and cash flows.

The Company relies heavily on communications and information systems to conduct its business. Any failure, interruption or breach in security of these systems could result in failures or disruptions in the Company’s customer relationship management, general ledger, deposits, servicing or loan origination systems. If any such failures, interruptions or security breaches of its communications or information systems occur, they may not be adequately addressed by the Company. Further, the occurrence of any such failures, interruptions or security breaches could damage the Company’s reputation, result in a loss of customer business, subject the Company to additional regulatory scrutiny or expose the Company to civil litigation and possible financial liability, any of which could have a material adverse effect on the Company’s results of operations, financial condition and cash flows.

The business of the Company is dependent on technology.

The financial services industry is undergoing rapid technological changes with frequent introductions of new technology-driven products and services. In addition to better serving customers, the effective use of technology increases efficiency and enables financial institutions to reduce costs. The Company’s future success depends in part upon its ability to address the needs of its customers by using technology to provide products and services that will satisfy customer demands for convenience as well as create additional efficiencies in its operations. Many of the Company’s competitors have substantially greater resources to invest in technological improvements. The Company may not be able to effectively implement new technology-driven products and services or be successful in marketing these products and services to its customers, which may negatively affect the Company’s results of operations, financial condition and cash flows.

The Company’s operations rely on external vendors.

The Company relies on certain external vendors to provide products and services necessary to maintain day-to-day operations of the Company. Accordingly, the Company’s operations are exposed to risk that these vendors will not perform in accordance with the contracted arrangements under service agreements. The failure of an external vendor to perform in accordance with the contracted arrangements under service agreements, because of

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changes in the vendor’s organizational structure, financial condition, support for existing products and services or strategic focus or for any other reason, could be disruptive to the Company’s operations, which could have a material adverse impact on the Company’s business and, in turn, the Company’s financial condition and results of operations.

The Company is subject to claims and litigation pertaining to intellectual property.

Banking and other financial services companies, such as the Company, rely on technology companies to provide information technology products and services necessary to support the Company’s day-to-day operations. Technology companies frequently enter into litigation based on allegations of patent infringement or other violations of intellectual property rights. In addition, patent holding companies seek to monetize patents they have purchased or otherwise obtained. Competitors of the Company’s vendors, or other individuals or companies, have from time to time claimed to hold intellectual property sold to the Company by its vendors. Such claims may increase in the future as the financial services sector becomes more reliant on information technology vendors. The plaintiffs in these actions frequently seek injunctions and substantial damages.

Regardless of the scope or validity of such patents or other intellectual property rights, or the merits of any claims by potential or actual litigants, the Company may have to engage in protracted litigation. Such litigation is often expensive, time-consuming, disruptive to the Company’s operations and distracting to management. If the Company is found to infringe one or more patents or other intellectual property rights, it may be required to pay substantial damages or royalties to a third-party. In certain cases, the Company may consider entering into licensing agreements for disputed intellectual property, although no assurance can be given that such licenses can be obtained on acceptable terms or that litigation will not occur. These licenses may also significantly increase the Company’s operating expenses. If legal matters related to intellectual property claims were resolved against the Company or settled, the Company could be required to make payments in amounts that could have a material adverse effect on its business, financial condition and results of operations.

The Company is subject to claims and litigation pertaining to fiduciary responsibility.

From time to time, customers make claims and take legal action pertaining to the Company’s performance of its fiduciary responsibilities. Whether customer claims and legal action related to the Company’s performance of its fiduciary responsibilities are founded or unfounded, if such claims and legal actions are not resolved in a manner favorable to the Company, they may result in significant financial liability, adversely affect the market perception of the Company and its products and services and/or impact customer demand for those products and services. Any financial liability or reputation damage could have a material adverse effect on the Company’s business, financial condition and results of operations.

The Company operates in a highly regulated environment and, as a result, is subject to extensive regulation and supervision.

The Company and the Bank are subject to extensive federal and state regulation and supervision. Banking regulations are primarily intended to protect depositors’ funds, federal deposit insurance funds and the banking system as a whole, not the Company’s shareholders. These regulations affect the Company’s lending practices, capital structure, investment practices, dividend policy and growth, among other things. Congress and federal regulatory agencies continually review banking laws, regulations and policies for possible changes. Any change in applicable regulations or federal or state legislation could have a substantial impact on the Company, the Bank and their respective operations.

The Dodd-Frank Act, enacted in July 2010, instituted major changes to the banking and financial institutions regulatory regimes in light of the recent performance of and government intervention in the financial services sector. Additional legislation and regulations or regulatory policies, including changes in interpretation or implementation of statutes, regulations or policies, could significantly affect the Company’s powers, authority

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and operations, or the powers, authority and operations of the Bank in substantial and unpredictable ways. Further, regulators have significant discretion and power to prevent or remedy unsafe or unsound practices or violations of laws by banks and bank holding companies in the performance of their supervisory and enforcement duties. The exercise of this regulatory discretion and power could have a negative impact on the Company. Failure to comply with laws, regulations or policies could result in sanctions by regulatory agencies, civil money penalties and/or reputation damage, which could have a material adverse effect on the Company’s business, financial condition and results of operations.

The Company is subject to losses resulting from fraudulent and negligent acts on the part of loan applicants, correspondents or other third parties.

The Company relies heavily upon information supplied by third parties, including the information contained in credit applications, property appraisals, title information, equipment pricing and valuation and employment and income documentation, in deciding which loans the Company will originate, as well as the terms of those loans. If any of the information upon which the Company relies is misrepresented, either fraudulently or inadvertently, and the misrepresentation is not detected prior to asset funding, the value of the asset may be significantly lower than expected, or the Company may fund a loan that it would not have funded or on terms it would not have extended. Whether a misrepresentation is made by the applicant or another third party, the Company generally bears the risk of loss associated with the misrepresentation. A loan subject to a material misrepresentation is typically unsellable or subject to repurchase if it is sold prior to detection of the misrepresentation. The sources of the misrepresentations are often difficult to locate, and it is often difficult to recover any of the monetary losses the Company may suffer.

The recent repeal of federal prohibitions on payment of interest on demand deposits could increase the Company’s interest expense.

All federal prohibitions on the ability of financial institutions to pay interest on demand deposit accounts were repealed as part of the Dodd-Frank Act beginning on July 21, 2011. Accordingly, financial institutions can now offer interest on demand deposits to compete for clients. The Company’s interest expense will increase and its net interest margin will decrease if it begins offering interest on demand deposits to attract additional customers or maintain current customers, which could have an adverse effect on the Company’s business, financial condition and results of operations.

The Company is subject to environmental liability risk associated with lending activities.

A significant portion of the Company’s loan portfolio is secured by real property. During the ordinary course of business, the Company may foreclose on and take title to properties securing certain loans. In doing so, there is a risk that hazardous or toxic substances could be found on these properties. If hazardous or toxic substances are found, the Company may be liable for remediation costs, as well as for personal injury and property damage. Environmental laws may require the Company to incur substantial expenses and may materially reduce the affected property’s value or limit the Company’s ability to use or sell the affected property. In addition, future laws or more stringent interpretations or enforcement policies with respect to existing laws may increase the Company’s exposure to environmental liability. Although the Company has policies and procedures to perform an environmental review before initiating any foreclosure action on real property, these reviews may not be sufficient to detect all potential environmental hazards. The remediation costs and any other financial liabilities associated with an environmental hazard could have a material adverse effect on the Company’s financial condition and results of operations.

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Risks Associated with the Company’s Common Stock

The Company’s corporate organizational documents and the provisions of Texas law to which it is subject may delay or prevent a change in control of the Company that a shareholder may favor.

The Company’s amended and restated articles of incorporation and amended and restated bylaws contain various provisions which may delay, discourage or prevent an attempted acquisition or change of control of the Company. These provisions include:

The Company’s articles of incorporation provide for noncumulative voting for directors and authorize the board of directors to issue shares of its preferred stock without shareholder approval and upon such terms as the board of directors may determine. The issuance of the Company’s preferred stock could have the effect of making it more difficult for a third party to acquire, or of discouraging a third party from acquiring, a controlling interest in the Company. In addition, certain provisions of Texas law, including a provision which restricts certain business combinations between a Texas corporation and certain affiliated shareholders, may delay, discourage or prevent an attempted acquisition or change in control of the Company.

There are restrictions on the Company’s ability to pay dividends.

Holders of the Company’s common stock are only entitled to receive such dividends as the Company’s Board of Directors may declare out of funds legally available for such payments. Although the Company has historically declared cash dividends on its common stock, it is not required to do so and there can be no assurance that the Company will pay dividends in the future. Any declaration and payment of dividends on common stock will depend upon the Company’s earnings and financial condition, liquidity and capital requirements, the general economic and regulatory climate, the Company’s ability to service any equity or debt obligations senior to the common stock and other factors deemed relevant by the Board of Directors.

The Company’s principal source of funds to pay dividends on the shares of common stock is cash dividends that the Company receives from the Bank. Various banking laws applicable to the Bank limit the payment of dividends and other distributions by the Bank to the Company, and may therefore limit the Company’s ability to pay dividends on its common stock. Further, if required payments on the Company’s outstanding junior subordinated debentures held by its unconsolidated subsidiary trusts are not made or are suspended, the Company will be prohibited from paying dividends on its common stock.

The holders of the Company’s junior subordinated debentures have rights that are senior to those of the Company’s shareholders.

As of December 31, 2012, the Company had $85.1 million in junior subordinated debentures outstanding that were issued to the Company’s unconsolidated subsidiary trusts. The subsidiary trusts purchased the junior subordinated debentures from the Company using the proceeds from the sale of trust preferred securities to third party investors. Payments of the principal and interest on the trust preferred securities are conditionally guaranteed by the Company to the extent not paid or made by each trust, provided the trust has funds available for such obligations.

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The junior subordinated debentures are senior to the Company’s shares of common stock. As a result, the Company must make interest payments on the junior subordinated debentures (and the related trust preferred securities) before any dividends can be paid on its common stock; and, in the event of the Company’s bankruptcy, dissolution or liquidation, the holders of the debentures must be satisfied before any distributions can be made to the holders of the common stock. Additionally, the Company has the right to defer periodic distributions on the junior subordinated debentures (and the related trust preferred securities) for up to five years, during which time the Company would be prohibited from paying dividends on its common stock. The Company’s ability to pay the future distributions depends upon the earnings of the Bank and dividends from the Bank to the Company, which may be inadequate to service the obligations.

None.

ITEM 2. PROPERTIES

As of December 31, 2012, the Company conducted business at two hundred thirteen (213) full-service banking centers. The Company’s headquarters are located at Prosperity Bank Plaza, 4295 San Felipe, in the Galleria area in Houston, Texas. The Company also owns or leases other facilities in which its banking centers are located as listed below by geographical market area. The expiration dates of the leases range from 2013 to 2020 and do not include renewal periods which may be available at the Company’s option.

The following table sets forth specific information regarding the banking centers located in each of the Company’s geographical market areas at December 31, 2012:

ITEM 3. LEGAL PROCEEDINGS

The Company and the Bank are defendants, from time to time, in legal actions arising from transactions conducted in the ordinary course of business. The Company and the Bank believe, after consultations with legal counsel, that the ultimate liability, if any, arising from such actions will not have a material adverse effect on their financial statements.

ITEM 4. MINE SAFETY DISCLOSURES

None.

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PART II.

ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED SHAREHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Common Stock Market Prices

The Company’s common stock is listed on the New York Stock Exchange under the symbol “PB.” Prior to December 28, 2011, the Company’s common stock was listed for trading under the symbol “PRSP” on the NASDAQ Global Select Market (“NASDAQ”). As of February 15, 2013, there were 56,997,694 shares outstanding and 2,970 shareholders of record. The number of beneficial owners is unknown to the Company at this time.

The following table presents the high and low intra-day sales prices for the common stock as reported by NASDAQ (through December 27, 2011) or the New York Stock Exchange (beginning December 28, 2011) during the two years ended December 31, 2012:

Dividends

Holders of common stock are entitled to receive dividends when, as and if declared by the Company’s Board of Directors out of funds legally available therefor. While the Company has declared dividends on its common stock since 1994, and paid quarterly dividends aggregating $0.80 per share in 2012 and $0.72 per share in 2011, there is no assurance that the Company will continue to pay dividends in the future. Future dividends on the common stock will depend upon the Company’s earnings and financial condition, liquidity and capital requirements, the general economic and regulatory climate, the Company’s ability to service any equity or debt obligations senior to the common stock and other factors deemed relevant by the Board of Directors of the Company.

As a holding company, the Company is ultimately dependent upon its subsidiaries to provide funding for its operating expenses, debt service and dividends. Various banking laws applicable to the Bank limit the payment of dividends and other distributions by the Bank to the Company, and may therefore limit the Company’s ability to pay dividends on its common stock. Regulatory authorities could impose administratively stricter limitations on the ability of the Bank to pay dividends to the Company if such limits were deemed appropriate to preserve certain capital adequacy requirements.

In addition, the Federal Reserve Board has indicated that bank holding companies should carefully review their dividend policy in relation to the organization’s overall asset quality, level of current and prospective earnings and level, composition and quality of capital. The guidance provides that the Company inform and consult with the Federal Reserve Board prior to declaring and paying a dividend that exceeds earnings for the period for which the dividend is being paid or that could result in an adverse change to the Company’s capital

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structure, including interest on the subordinated debentures underlying the Company’s trust preferred securities. If required payments on the Company’s outstanding junior subordinated debentures held by its unconsolidated subsidiary trusts are not made or suspended, the Company will be prohibited from paying dividends on its common stock.

The cash dividends declared per share by quarter (and paid on the first business day of the subsequent quarter except for the fourth quarter of 2012 which was paid on December 31, 2012) for the Company’s last two fiscal years were as follows:

Recent Sales of Unregistered Securities

None.

Securities Authorized for Issuance under Equity Compensation Plans

As of December 31, 2012, the Company had outstanding stock options granted under three stock award plans, all of which were approved by the Company’s shareholders. As of such date, the Company also had outstanding stock options granted under stock award plans that it assumed in connection with various acquisition transactions. The following table provides information as of December 31, 2012 regarding the Company’s equity compensation plans under which the Company’s equity securities are authorized for issuance:

Purchases of Equity Securities by the Issuer and Affiliated Purchasers

None.

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Performance Graph

The following Performance Graph compares the cumulative total shareholder return on the Company’s common stock for the period beginning at the close of trading on December 31, 2007 to December 31, 2012, with the cumulative total return of the S&P 500 Total Return Index and the Nasdaq Bank Index for the same period. Dividend reinvestment has been assumed. The Performance Graph assumes $100 invested on December 31, 2007 in the Company’s common stock, the S&P 500 Total Return Index and the Nasdaq Bank Index. The historical stock price performance for the Company’s common stock shown on the graph below is not necessarily indicative of future stock performance.

Copyright^© 2012 Standard & Poor’s, a division of The McGraw-Hill Companies Inc. All rights reserved. (www.researchdatagroup.com/S&P.htm)

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The following selected consolidated financial data of the Company for, and as of the end of, each of the years in the five-year period ended December 31, 2012, is derived from and should be read in conjunction with the Company’s consolidated financial statements and the notes thereto appearing elsewhere in this Annual Report on Form 10-K.

(Table continued on next page)

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Special Cautionary Notice Regarding Forward-Looking Statements

Statements and financial discussion and analysis contained in this Annual Report on Form 10-K that are not statements of historical fact constitute forward-looking statements made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are based on assumptions and involve a number of risks and uncertainties, many of which are beyond the Company’s control. Many possible events or factors could affect the future financial results and performance of the Company and could cause such results or performance to differ materially from those expressed in the forward-looking statements. These possible events or factors include, but are not limited to:

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A forward-looking statement may include a statement of the assumptions or bases underlying the forward-looking statement. The Company believes it has chosen these assumptions or bases in good faith and that they are reasonable. However, the Company cautions you that assumptions or bases almost always vary from actual results, and the differences between assumptions or bases and actual results can be material. Therefore, the Company cautions you not to place undue reliance on its forward-looking statements. The forward-looking statements speak only as of the date the statements are made. The Company undertakes no obligation to publicly update or otherwise revise any forward-looking statements, whether as a result of new information, future events or otherwise.

Management’s Discussion and Analysis of Financial Condition and Results of Operations analyzes the major elements of the Company’s balance sheets and statements of income. This section should be read in conjunction with the Company’s consolidated financial statements and accompanying notes and other detailed information appearing elsewhere in this Annual Report on Form 10-K.

Overview

The Company generates the majority of its revenues from interest income on loans, service charges on customer accounts and income from investment in securities. In 2012, the Company added additional products and services including trust services, credit card, mortgage lending and independent sales organization (ISO) sponsorship operations. The revenues are partially offset by interest expense paid on deposits and other borrowings and noninterest expenses such as administrative and occupancy expenses. Net interest income is the difference between interest income on earning assets such as loans and securities and interest expense on liabilities such as deposits and borrowings which are used to fund those assets. Net interest income is the Company’s largest source of revenue. The level of interest rates and the volume and mix of earning assets and interest-bearing liabilities impact net interest income and margin. The Company has recognized increased net interest income due primarily to an increase in the volume of interest-earning assets.

Three principal components of the Company’s growth strategy are internal growth, stringent cost control practices and acquisitions, including strategic merger transactions and FDIC assisted transactions. The Company focuses on continual internal growth. Each banking center is operated as a separate profit center, maintaining separate data with respect to its net interest income, efficiency ratio, deposit growth, loan growth and overall profitability. Banking center presidents and managers are accountable for performance in these areas and compensated accordingly. The Company also focuses on maintaining stringent cost control practices and

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policies. The Company has centralized many of its critical operations, such as data processing and loan processing. Management believes that this centralized infrastructure can accommodate substantial additional growth while enabling the Company to minimize operational costs through certain economies of scale. The Company also intends to continue to seek expansion opportunities. During 2012, the Company completed four acquisitions including Texas Bankers, Inc., The Bank Arlington, ASB and Community National Bank. Combined these acquisitions added forty-one (41) banking centers.

Net income was $167.9 million, $141.7 million and $127.7 million for the years ended December 31, 2012, 2011 and 2010, respectively, and diluted earnings per share were $3.23, $3.01 and $2.73, respectively, for these same periods. The change in net income during both 2012 and 2011 was principally due to an increase in net interest income resulting from balance sheet growth from acquisitions. The Company posted returns on average assets of 1.35%, 1.47% and 1.38% and returns on average equity of 9.10%, 9.36% and 9.08% for the years ended December 31, 2012, 2011 and 2010, respectively. The Company’s efficiency ratio was 43.48% in 2012, 42.76% in 2011 and 44.83% in 2010. The efficiency ratio is calculated by dividing total noninterest expense (excluding credit loss provisions and impairment write-down on securities) by net interest income plus noninterest income (excluding net gains and losses on the sale of securities and assets). Additionally, taxes are not part of this calculation.

Total assets at December 31, 2012 and 2011 were $14.58 billion and $9.82 billion, respectively. Total deposits at December 31, 2012 and 2011 were $11.64 billion and $8.06 billion, respectively. Total loans were $5.18 billion at December 31, 2012, an increase of $1.41 billion or 37.5% compared with $3.77 billion at December 31, 2011. At December 31, 2012, the Company had $5.7 million in nonperforming loans and its allowance for credit losses was $52.6 million compared with $3.6 million in nonperforming loans and an allowance for credit losses of $51.6 million at December 31, 2011. Shareholders’ equity was $2.09 billion and $1.57 billion at December 31, 2012 and 2011, respectively.

Recent Developments

During 2012, the Company completed four acquisitions. These acquisitions increased total assets, loans and deposits on their respective acquisition date as detailed in the table below (dollars in thousands). Additionally, the Company completed its acquisition of East Texas Financial Services, Inc. on January 1, 2013 and signed a definitive agreement on December 10, 2012 to purchase Coppermark Bancshares, Inc.

Acquisition of Texas Bankers, Inc.—On January 1, 2012, the Company completed the acquisition of Texas Bankers, Inc. and its wholly-owned subsidiary, Bank of Texas, Austin, Texas. The three (3) Bank of Texas banking offices in the Austin, Texas CMSA consisted of a location in Rollingwood, which was consolidated with the Company’s Westlake location and remains in Bank of Texas’ Rollingwood banking office; one banking center in downtown Austin, which was consolidated into the Company’s downtown Austin location; and another banking center in Thorndale.

Texas Bankers, Inc. on a consolidated basis, reported total assets of $77.0 million, total loans of $27.6 million and total deposits of $70.4 million as of December 31, 2011. Under the terms of the acquisition agreement, the Company issued 314,953 shares of Company common stock for all outstanding shares of Texas Bankers capital stock, resulting in an acquisition date fair value of $12.7 million, based on the Company’s

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closing stock price of $40.35. The Company recognized goodwill of $6.1 million which is calculated as the excess of both the consideration exchanged and liabilities assumed as compared to the fair value of identifiable assets acquired.

Acquisition of The Bank Arlington—On April 1, 2012, the Company completed the acquisition of The Bank Arlington. The Bank Arlington operated one banking office in Arlington, Texas, in the Dallas/Fort Worth CMSA.

As of March 31, 2012, The Bank Arlington reported total assets of $37.3 million, total loans of $22.9 million and total deposits of $33.2 million. Under the terms of the acquisition agreement, the Company issued 135,347 shares of Company common stock for all outstanding shares of The Bank Arlington capital stock, resulting in an acquisition date fair value of $6.2 million, based on the Company’s closing stock price of $45.80. The Company recognized goodwill of $2.1 million which is calculated as the excess of both the consideration exchanged and liabilities assumed as compared to the fair value of identifiable assets acquired.

Acquisition of American State Financial Corporation—On July 1, 2012, the Company completed the acquisition of American State Financial Corporation and its wholly owned subsidiary American State Bank (collectively referred to as “ASB”). ASB operated thirty-seven (37) full service banking offices in eighteen (18) counties across West Texas.

On the date of acquisition, the Company recorded total assets of $3.11 billion, total loans of $1.15 billion and total deposits of $2.50 billion. Under the terms of the acquisition agreement, the Company issued 8,524,835 shares of Company common stock plus $178.5 million in cash for all outstanding shares of American State Financial Corporation capital stock, for total merger consideration of $536.8 million and recognized goodwill of $274.1 million.

Acquisition of Community National Bank—On October 1, 2012, the Company completed the acquisition of Community National Bank, Bellaire, Texas. Community National Bank operated one (1) banking office in Bellaire, Texas, in the Houston Metropolitan Area.

As of September 30, 2012, Community National Bank reported total assets of $182.0 million, total loans of $68.0 million and total deposits of $164.6 million. Under the terms of the acquisition agreement, the Company issued 372,282 shares of Company common stock plus $11.4 million in cash for all outstanding shares of Community National Bank capital stock, for total merger consideration of $27.3 million, based on the Company’s closing stock price of $42.62. The Company recognized goodwill of $10.3 million which is calculated as the excess of both the consideration exchanged and liabilities assumed as compared to the fair value of identifiable assets acquired.

Acquisition of East Texas Financial Services, Inc.—On January 1, 2013, the Company completed the previously announced acquisition of East Texas Financial Services, Inc. (OTC BB: FFBT) and its wholly-owned subsidiary, First Federal Bank Texas (“Firstbank”). Firstbank operated four (4) banking offices in the Tyler MSA, including three locations in Tyler, Texas and one location in Gilmer, Texas. As of December 31, 2012, East Texas Financial Services reported, on a consolidated basis, total assets of $165.0 million, total loans of $129.3 million and total deposits of $112.3 million.

Pursuant to the terms of the acquisition agreement, the Company issued 530,940 shares of the Company’s common stock for all outstanding shares of East Texas Financial Services capital stock resulting in an acquisition date fair value of $22.3 million, based on the Company’s closing stock price of $42.00 and recognized goodwill of approximately $5.5 million which is calculated as the excess of both the consideration exchanged and liabilities assumed compared to the fair value of the assets acquired. The Company is currently in the process of obtaining fair values for certain acquired assets and assumed liabilities and therefore the estimates are preliminary.

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Pending Acquisition of Coppermark Bancshares Inc.—On December 10, 2012, the Company entered into a definitive agreement to acquire Coppermark Bancshares, Inc. and its wholly-owned subsidiary, Coppermark Bank (“Coppermark”) headquartered in Oklahoma City, Oklahoma. Coppermark operates nine (9) full-service banking offices: six (6) in Oklahoma City, Oklahoma and surrounding areas and three (3) in the Dallas, Texas area. As of December 31, 2012, Coppermark reported, on a consolidated basis, total assets of $1.3 billion, total loans of $853.4 million and total deposits of $1.2 billion.

Under the terms of the acquisition agreement, the Company will issue approximately 3,258,845 shares of Company common stock plus $60.0 million in cash for all outstanding shares of Coppermark Bancshares capital stock, subject to certain conditions and potential adjustments. Pending the satisfaction of closing conditions, the closing is expected to occur in early 2013.

Critical Accounting Policies

The Company’s significant accounting policies are integral to understanding the results reported. The Company’s accounting policies are described in detail in Note 1 to the consolidated financial statements, appearing elsewhere is this Annual Report on Form 10-K. The Company believes that of its significant accounting policies, the following may involve a higher degree of judgment and complexity:

Allowance for Credit Losses—The allowance for credit losses is established through charges to earnings in the form of a provision for credit losses. Management has established an allowance for credit losses which it believes is adequate for estimated losses in the Company’s loan portfolio. Based on an evaluation of the loan portfolio, management presents a monthly review of the allowance for credit losses to the Bank’s Board of Directors, indicating any change in the allowance since the last review and any recommendations as to adjustments in the allowance. In making its evaluation, management considers factors such as historical loan loss experience, industry diversification of the Company’s commercial loan portfolio, the amount of nonperforming assets and related collateral, the volume, growth and composition of the Company’s loan portfolio, current economic conditions that may affect the borrower’s ability to pay and the value of collateral, the evaluation of the Company’s loan portfolio through its internal loan review process and other relevant factors. Portions of the allowance may be allocated for specific credits; however, the entire allowance is available for any credit that, in management’s judgment, should be charged off. Charge-offs occur when loans are deemed to be uncollectible. For further discussion of the methodology used in the determination of the allowance for credit losses, refer to the “Allowance for Credit Losses” section in this financial review and Note 1 to the consolidated financial statements.

Goodwill and Intangible Assets—Goodwill and intangible assets that have indefinite useful lives are subject to an impairment test at least annually, or more often, if events or circumstances indicate that it is more likely than not that the fair value of Prosperity Bank, the Company’s only reporting unit with assigned goodwill, is below the carrying value of its equity. On January 1, 2012, the Company adopted Accounting Standard Update No. 2011-08, “Intangibles—Goodwill and Other (Topic 350): Testing Goodwill for Impairment,” (ASU 2011-08), which allows companies to use a qualitative approach to assess goodwill for impairment. The provisions of ASU 2011-08 give companies the option to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount as a basis for determining the need to perform step one of the annual test for goodwill impairment. An entity has an unconditional option to bypass the qualitative assessment described in the preceding paragraph for any reporting unit in any period and proceed directly to performing the first step of the goodwill impairment test. An entity may resume performing the qualitative assessment in any subsequent period.

If the Company bypasses the qualitative assessment, a two-step goodwill impairment test is performed. The two-step process begins with an estimation of the fair value of the Company’s reporting unit compared with its carrying value. If the carrying amount exceeds the fair value of the reporting unit, a second test is completed comparing the implied fair value of the reporting unit’s goodwill to its carrying value to measure the amount of impairment.

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Estimating the fair value of the Company’s reporting unit is a subjective process involving the use of estimates and judgments, particularly related to future cash flows of the reporting unit, discount rates (including market risk premiums) and market multiples. Material assumptions used in the valuation models include comparable public company price multiples used in the terminal value, future cash flows and the market risk premium component of the discount rate. The estimated fair value of the reporting unit is determined using a blend of two commonly used valuation techniques: the market approach and the income approach. The Company gives consideration to both valuation techniques, as either technique can be an indicator of value. For the market approach, valuations of the reporting unit were based on an analysis of relevant price multiples in market trades in companies with similar characteristics. For the income approach, estimated future cash flows (derived from internal forecasts and economic expectations) and terminal value (value at the end of the cash flow period, based on price multiples) were discounted. The discount rate was based on the imputed cost of equity capital.

The Company had no intangible assets with indefinite useful lives at December 31, 2012. Other identifiable intangible assets that are subject to amortization are amortized on an accelerated basis over the years expected to be benefited, which the Company believes is between eight and ten years. These amortizable intangible assets are reviewed for impairment if circumstances indicate their value may not be recoverable based on a comparison of fair value to carrying value. Based on the Company’s annual goodwill impairment test as of September 30, 2012, management does not believe any of its goodwill is impaired as of December 31, 2012, because the fair value of the Company’s equity substantially exceeded its carrying value. While the Company believes no impairment existed at December 31, 2012, under accounting standards applicable at that date, different conditions or assumptions, or changes in cash flows or profitability, if significantly negative or unfavorable, could have a material adverse effect on the outcome of the Company’s impairment evaluation and financial condition or future results of operations.

Stock-Based Compensation—The Company accounts for stock-based employee compensation plans using the fair value-based method of accounting. The Company’s results of operations reflect compensation expense for all employee stock-based compensation, including the unvested portion of stock options granted prior to 2003. The fair value of stock options granted is estimated at the date of grant using the Black-Scholes option-pricing model. This model requires the input of subjective assumptions including stock price volatility and employee turnover that are utilized to measure compensation expense.

Other-Than-Temporarily Impaired Securities—When the fair value of a security is below its amortized cost, and depending on the length of time the condition exists and the extent the fair market value is below amortized cost, additional analysis is performed to determine whether an impairment exists. Available for sale and held to maturity securities are analyzed quarterly for possible other-than-temporary impairment. The analysis considers (i) the length of time and the extent to which the fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer, (iii) whether the market decline was affected by macroeconomic conditions, and (iv) whether the entity has the intent to sell the debt security or more likely than not will be required to sell the debt security before its anticipated recovery. Often, the information available to conduct these assessments is limited and rapidly changing, making estimates of fair value subject to judgment. If actual information or conditions are different than estimated, the extent of the impairment of the security may be different than previously estimated, which could have a material effect on the Company’s results of operations and financial condition.

Fair Values of Financial Instruments. The Company determines the fair market values of financial instruments based on the fair value hierarchy established which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. There are three levels of inputs that may be used to measure fair value. Level 1 inputs include quoted market prices, where available. If such quoted market prices are not available Level 2 inputs are used. These inputs are based upon internally developed models that primarily use observable market-based parameters. Level 3 inputs are unobservable inputs which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability.

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Results of Operations

Net Interest Income

The Company’s operating results depend primarily on its net interest income, which is the difference between interest income on interest-earning assets, including securities and loans, and interest expense incurred on interest-bearing liabilities, including deposits and other borrowed funds. Interest rate fluctuations, as well as changes in the amount and type of earning assets and liabilities, combine to affect net interest income. The Company’s net interest income is affected by changes in the amount and mix of interest-earning assets and interest-bearing liabilities, referred to as a “volume change.” It is also affected by changes in yields earned on interest-earning assets and rates paid on interest-bearing deposits and other borrowed funds, referred to as a “rate change.”

2012 versus 2011. Net interest income before the provision for credit losses for 2012, was $380.7 million compared with $326.7 million for 2011, an increase of $54.0 million or 16.5%. The increase in net interest income was primarily due to an increase in average interest-earning assets of $2.65 billion or 31.9% during 2012, and a decrease in the average rate paid on interest-bearing liabilities of 24 basis points. The increase in average earning assets was due to the four acquisitions completed during 2012. Interest income was $419.8 million in 2012, an increase of $47.9 million over 2011. Interest income on loans was $271.3 million for 2012, an increase of $57.1 million or 26.6% compared with 2011 due in part to an increase in average loans outstanding of $865.5 million. Additionally, during 2012 interest income on loans benefited from purchase accounting loan discount accretion of $26.4 million which partially offset the decrease in interest rates on the loan portfolio. The Company had remaining accretable discounts on purchased loans of $63.6 million outstanding at December 31, 2012. Interest income on securities was $148.4 million during 2012, a decrease of $9.2 million over 2011 due, in part, to an increase in the amortization of security premiums of $38.2 million for 2012 compared with 2011. Average interest-bearing liabilities increased $1.81 billion for 2012 compared to 2011 and average rate paid decreased from 0.72% to 0.48% for the same time period resulting in an overall decrease in interest expense of $6.1 million. During 2012, average noninterest bearing deposits increased $642.8 million from $1.80 billion during 2011 to $2.44 billion during 2012. This increase in low-cost noninterest bearing funds contributed to a decrease in total cost of funds to 0.37% during 2012 from 0.56% during 2011.

Net interest margin on a tax equivalent basis, defined as net interest income divided by average interest-earning assets, for 2012 was 3.53%, a decrease of 45 basis points compared with 3.98% for 2011.

2011 versus 2010. Net interest income before the provision for credit losses for the year ended December 31, 2011 was $326.7 million compared with $318.1 million for the year ended December 31, 2010, an increase of $8.5 million or 2.7%. The improvement in net interest income for 2011 was principally due to a $349.0 million or 4.4% increase in average interest-earning assets to $8.301 billion at December 31, 2011 compared with $7.952 billion at December 31, 2010. The average rate paid on interest-bearing liabilities decreased 34 basis points from 1.06% for the year ended December 31, 2010 to 0.72% for the year ended December 31, 2011 and the average yield on interest-earning assets decreased 36 basis points from 4.84% at December 31, 2010 to 4.48% at December 31, 2011. At December 31, 2011, period end demand deposits represented an important component of funding and were 24.5% of total period end deposits compared with 22.4% at December 31, 2010.

Net interest margin on a tax equivalent basis, defined as net interest income divided by average interest-earning assets, for 2011 was 3.98%, a decrease of 6 basis points compared with 4.04% for 2010.

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The following table presents, for the periods indicated, the total dollar amount of average balances, interest income from average interest-earning assets and the resultant yields, as well as the interest expense on average interest-bearing liabilities, expressed both in dollars and rates. Except as indicated in the footnotes, no tax-equivalent adjustments were made and all average balances are daily average balances. Any nonaccruing loans have been included in the table as loans carrying a zero yield.