INTERNATIONAL BANCSHARES CORP - Annual Report: 2011 (Form 10-K)

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K

Commission file number: 0-09439

INTERNATIONAL BANCSHARES CORPORATION
(Exact Name of Registrant as Specified in its Charter)

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

         Securities Registered Pursuant to Section 12(g) of the Act:

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

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

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

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

         Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K Section 229.405 of this chapter is not contained herein, and will not be contained, to the best of Registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ý

         Indicate by check mark if 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 "small reporting company" in Rule 12b-2 of the Exchange Act.

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

         The aggregate market value of the voting stock held by non-affiliates of the Registrant as of June 30, 2011 was $1,135,534,000 based on the closing sales price per share of the Registrant's common stock on such date as reported by NASDAQ.

         As of February 21, 2012, there were 67,278,237 shares of the Registrant's Common Stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

         Portions of the following documents are incorporated by reference into the designated parts of this Form 10-K: (a) Annual Report to security holders for the fiscal year ended December 31, 2011 (in Parts I and II) and (b) Proxy Statement relating to the Company's 2012 Annual Meeting of Shareholders (in Part III).

CONTENTS

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Special Cautionary Notice Regarding Forward Looking Information

        Certain matters discussed in this report, excluding historical information, include forward-looking statements, within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and are subject to the safe harbor created by these sections. Although International Bancshares Corporation (the "Company") believes such forward-looking statements are based on reasonable assumptions, no assurance can be given that every objective will be reached. The words "estimate," "expect," "intend," "believe" and "project," as well as other words or expressions of a similar meaning are intended to identify forward-looking statements. Readers are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date of this report. Such statements are based on current expectations, are inherently uncertain, are subject to risks and should be viewed with caution. Actual results and experience may differ materially from the forward-looking statements as a result of many factors.

        Risk factors that could cause actual results to differ materially from any results that are projected, forecasted, estimated or budgeted by the Company in forward-looking statements include, among others, the following possibilities:

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Local, regional, national and international economic business conditions and the impact they may have on the Company, the Company's customers, and such customers' ability to transact profitable business with the Company, including the ability of its borrowers to repay their loans according to their terms or a change in the value of the related collateral.



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Volatility and disruption in national and international financial markets.



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Government intervention in the U.S. financial system.



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The Company relies, in part, on external financing to fund the Company's operations and the unavailability of such funds in the future could adversely impact the Company's growth strategy and prospects.



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Changes in consumer spending, borrowings and savings habits.



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Changes in interest rates and market prices, which could reduce the Company's net interest margins, asset valuations and expense expectations, including, without limitation, the repeal of federal prohibitions on the payment of interest on demand deposits.



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Changes in the capital markets utilized by the Company and its subsidiaries, including changes in the interest rate environment that may reduce margins.



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Changes in state and/or federal laws and regulations to which the Company and its subsidiaries, as well as their customers, competitors and potential competitors, are subject, including, without limitation, the impact of the Consumer Financial Protection Bureau as a new regulator of financial institutions, changes in the accounting, tax and regulatory treatment of trust preferred securities, as well as changes in banking, tax, securities, insurance and employment, environmental and immigration laws and regulations and the risk of litigation that may follow.



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Changes in U.S.—Mexico trade, including, without limitation, reductions in border crossings and commerce resulting from the Homeland Security Programs called "US-VISIT," which is derived from Section 110 of the Illegal Immigration Reform and Immigrant Responsibility Act of 1996.



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The loss of senior management or operating personnel.



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Increased competition from both within and outside the banking industry.



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The timing, impact and other uncertainties of the Company's potential future acquisitions including the Company's ability to identify suitable potential future acquisition candidates, the success or

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failure in the integration of their operations and the Company's ability to maintain its current branch network and to enter new markets successfully and capitalize on growth opportunities.

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Changes in the Company's ability to pay dividends on its Preferred Stock or Common Stock.



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Additions to the Company's loan loss allowance as a result of changes in local, national or international conditions which adversely affect the Company's customers, including, without limitation, lower real estate values or environmental liability risks associated with foreclosed properties.



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Greater than expected costs or difficulties related to the development and integration of new products and lines of business.



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Impairment of carrying value of goodwill could negatively impact our earnings and capital.



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Changes in the soundness of other financial institutions with which the Company interacts.



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Political instability in the United States or Mexico.



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Technological changes or system failure or breaches of our network security could subject us to increased operating costs as well as litigation and other liabilities.



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Acts of war or terrorism.



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Natural disasters.



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Reduced earnings resulting from the write down of the carrying value of securities held in our securities available-for-sale portfolio following a determination that the securities are other-than-temporarily impaired.



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The effect of changes in accounting policies and practices as may be adopted by the regulatory agencies, as well as the Public Company Accounting Oversight Board, the Financial Accounting Standards Board and other accounting standards setters.



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The costs and effects of regulatory developments, including the resolution of regulatory or other governmental inquiries and the results of regulatory examinations or reviews.



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The effect of final rules amending Regulation E that prohibit financial institutions from charging consumer fees for paying overdrafts on ATM and one-time debit card transactions, unless the consumer consents or opts-in to the overdraft service for those types of transactions, as well as the effect of any other regulatory or legal developments that limit overdraft services.



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The reduction of income and possible increase in required capital levels related to the adoption of new legislation, including, without limitation, the Dodd-Frank Regulatory Reform Act and the implementing rules and regulations, including the Federal Reserve's new interim final rule that establishes debit card interchange fee standards and prohibits network exclusivity arrangements and routing restrictions that is negatively affecting interchange revenue from debit card transactions as well as revenue from consumer services.



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The enhanced due diligence burden imposed on banks under the proposed rules of the banking agencies related to the banks' inability to rely on credit ratings under Dodd-Frank which may result in a limitation on the types of securities certain banks will be able to purchase as a result of the due diligence burden.



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The Company may be adversely affected by its continued participation in the Capital Purchase Program (the "CPP").



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The Company's success at managing the risks involved in the foregoing items, or a failure or circumvention of the Company's internal controls and risk management, policies and procedures.

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        Forward-looking statements speak only as of the date on which such statements are made. It is not possible to foresee or identify all such factors. The Company makes no commitment to update any forward-looking statement, or to disclose any facts, events or circumstances after the date hereof that may affect the accuracy of any forward-looking statement, unless required by law.

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Item 1.    Business

General

        The Company is a financial holding company with its principal corporate offices in Laredo, Texas. Four bank subsidiaries provide commercial and retail banking services through main banking and branch facilities located in communities in South, Central and Southeast Texas and the State of Oklahoma. The Company was originally incorporated under the General Corporation Law of the State of Delaware in 1979. Effective June 7, 1995, the Company's state of incorporation was changed from Delaware to Texas. The Company was organized for the purpose of operating as a bank holding company within the meaning of the Bank Holding Company Act of 1956, as amended (the "BHCA"), and as such, is subject to supervision and regulation by the Board of Governors of the Federal Reserve System (the "FRB"). As a registered bank holding company, the Company may own one or more banks and may engage directly, or through subsidiary corporations, in those activities closely related to banking which are specifically permitted under the BHCA and by the FRB. Effective March 13, 2000, the Company became certified as a financial holding company. As a financial holding company, the Company may engage in a broad list of financial and non-financial activities. The Company's principal assets at December 31, 2011 consisted of all the outstanding capital stock of four Texas state banking associations (the "Banks" or "bank subsidiaries"). All of the Company's bank subsidiaries are members of the Federal Deposit Insurance Corporation (the "FDIC").

        The bank subsidiaries are in the business of gathering funds from various sources and investing these funds in order to earn a return. Funds gathering primarily takes the form of accepting demand and time deposits from individuals, partnerships, corporations and public entities. Investments principally are made in loans to various individuals and entities as well as in debt securities of the U.S. Government and various other entities whose payments are guaranteed by the U.S. Government. Historically, the bank subsidiaries have primarily focused on providing commercial banking services to small and medium sized businesses located in their trade areas and international banking services. In recent years, the bank subsidiaries have also emphasized consumer and retail banking, including mortgage lending, as well as branches situated in retail locations and shopping malls; however, during the fourth quarter of 2011 the Company closed fifty-five in-store branches as a result of reduced levels of revenue resulting from regulatory changes limiting interchange fee income. The branches were closed in order to align the Company's expenses with the reduced levels of revenue.

        The Company's philosophy focuses on customer service as represented by its motto, "We Do More." The Banks maintain a strong commitment to their local communities by, among other things, appointing selected members of the communities in which the Banks' branches are located to local advisory boards (the "local boards"). The local boards direct the operations of the branches, with the supervision of the lead Bank's board of directors, and assist in introducing prospective customers to the Banks as well as developing or modifying products and services to meet customer needs. The Banks function largely on a decentralized basis and the Company believes that such decentralized structure enhances the commitment of the Banks to the communities in which their branches are located. In contrast to many of their principal competitors, the credit decisions of the Banks are made locally and promptly. The Company believes that the knowledge and expertise afforded by the local boards are key components to sound credit decisions. Expense control is an essential element in the Company's profitability. The Company has centralized virtually all of the Banks' back office support and investment functions in order to achieve consistency and cost efficiencies in the delivery of products and services.

        On July 28, 1980, the Company acquired all of the outstanding shares of its predecessor, International Bank of Commerce ("IBC"), which is today the flagship bank of the Company, representing the majority of the Company's banking assets. IBC was chartered under the banking laws of Texas in 1966 and has its principal place of business at 1200 San Bernardo Avenue, Laredo, Webb County, Texas. It is a wholly-owned subsidiary of the Company. Since the acquisition of the flagship bank in 1980, the Company has

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formed three banks: (i) Commerce Bank, a Texas state banking association which commenced operations in 1982, located in Laredo, Texas ("Commerce Bank"); (ii) International Bank of Commerce, Brownsville, a Texas state banking association which commenced operations in 1984, located in Brownsville, Texas ("IBC-Brownsville"); and (iii) International Bank of Commerce, Zapata, a Texas state banking association which commenced operations in 1984, located in Zapata, Texas ("IBC-Zapata").

        During the last several years, the Company has acquired various financial institutions and banking assets in its trade area and expanded its trade area to the State of Oklahoma. The community-focus of the subsidiary banks and the involvement of the local boards has resulted in the Company becoming aware of acquisition possibilities in the ordinary course of its business and in many instances before other potential purchasers. The Company's decision to pursue an acquisition is based on a multitude of factors, including the ability to efficiently assimilate the operations and assets of the acquired entity, the cost efficiencies to be attained and the growth potential of the market.

        The Company also has five direct non-banking subsidiaries. They are (i) IBC Life Insurance Company, a Texas chartered subsidiary which reinsures a small percentage of credit life and accident and health risks related to loans made by bank subsidiaries, (ii) IBC Trading Company, an export trading company which is currently inactive, (iii) IBC Subsidiary Corporation, a second-tier bank holding company incorporated in the State of Delaware, (iv) IBC Capital Corporation, a company incorporated in the State of Delaware for the purpose of holding certain investments of the Company and (v) Premier Tierra Holdings, Inc., a liquidating subsidiary formed under the laws of the State of Texas. The Company owns a fifty percent interest in Gulfstar Group I, Ltd. and related entities, which are involved in investment banking activities. The Company also owns a controlling interest in three merchant banking entities.

Website Access to Reports

        The Company makes its annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports, filed or furnished pursuant to section 13(a) or 15(d) of the Securities Exchange Act of 1934 available free of charge on or through the Company's internet website, www.ibc.com, as soon as reasonably practicable after such materials are electronically filed with, or furnished to, the Securities and Exchange Commission ("SEC"). Additionally, the Company has posted on its website a code of ethics that applies to its directors and executive officers (including the Company's chief executive officer and financial officer). The Company's website also includes the charter for its Audit Committee and the Company's Excessive or Luxury Expenditure Policy. The Company's website will also include the Proxy Statement relating to the Company's 2012 Annual Meeting of Shareholders upon filing of the definitive Proxy Statement with the SEC.

Services and Employees

        The Company, through its bank subsidiaries, IBC, Commerce Bank, IBC-Zapata and IBC-Brownsville, is engaged in the business of banking, including the acceptance of checking and savings deposits and the making of commercial, real estate, personal, home improvement, automobile and other installment and term loans. Certain of the bank subsidiaries are very active in facilitating international trade along the United States border with Mexico and elsewhere. The international banking business of the Company includes providing letters of credit, making commercial and industrial loans, and providing a nominal amount of currency exchange. Each bank subsidiary also offers other related services, such as credit cards, travelers' checks, safety deposit, collection, notary public, escrow, drive-up and walk-up facilities and other customary banking services. Additionally, each bank subsidiary makes available certain securities products through third party providers. The bank subsidiaries also make banking services available during traditional and nontraditional banking hours through their network of 378 automated teller machines, and through their 217 branches situated in retail locations and shopping malls. Additionally, IBC introduced IBC Bank Online, an Internet banking product, in order to provide customers online access to banking information and services 24 hours a day.

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        The Company owns U.S. service mark registrations for "INTERNATIONAL BANK OF COMMERCE," "INTERNATIONAL BANK OF COMMERCE CENTRE," "OVERDRAFT COURTESY," "IBC," "IBC CONNECTION," "IBC ELITE," "IBC ELITE ADVANTAGE," "IBC BANK," "BIZ RITE CHECKING," "GOT YOU COVERED," "FREE BEE," "IT'S A BRIGHTER CHRISTMAS," a design mark depicting a bee character, a design mark depicting the United States and Mexico, and a design mark depicting "IBC" with the United States and Mexico. In addition, the Company owns Texas service mark registrations for "RITE CHECKING," "THE CLUB," "WALL STREET INTERNATIONAL," "INTERNATIONAL BANK OF COMMERCE," "WE DO MORE," a composite mark depicting "CHECK'N SAVE" with a design, a composite mark depicting "WALL STREET INTERNATIONAL," with a design and a design mark depicting the United States and Mexico. The Company also owns Oklahoma service mark registrations for "CHECK 'N SAVE," "RITE CHECKING," "THE CLUB," and "WE DO MORE." The Company also owns pending applications for federal registration of other proprietary service marks and is regularly investigating the availability of service mark registrations related to certain proprietary products.

        No material portion of the business of the Company may be deemed seasonal and the deposit and loan base of the Company's bank subsidiaries is diverse in nature. There has been no material effect upon the Company's capital expenditures, earnings or competitive position as a result of Federal, State or local environmental regulation.

        As of December 31, 2011, the Company and its subsidiaries employed approximately 2,721 persons full-time and 667 persons part-time.

Competition

        The Company is the third largest independent Texas bank holding company. The primary market area of the Company is South, Central and Southeast Texas, an area bordered on the east by the Galveston area, to the northwest by Roundrock, to the southwest by Del Rio and to the southeast by Brownsville, as well as the State of Oklahoma. The Company has increased its market share in its primary market area over the last several years through strategic acquisitions. The Company, through its bank subsidiaries, competes for deposits and loans with other commercial banks, savings and loan associations, credit unions and non-bank entities, which non-bank entities serve as an alternative to traditional financial institutions and are considered to be formidable competitors. The percentage of bank-related services being provided by non-bank entities has increased dramatically during the last several years.

        The Company and its bank subsidiaries do a large amount of business for customers domiciled in Mexico, with an emphasis in Northern Mexico. Deposits from persons and entities domiciled in Mexico comprise a large and stable portion of the deposit base of the Company's bank subsidiaries. Such deposits comprised approximately 29%, 30% and 31% of the bank subsidiaries' total deposits for the three years ended December 31, 2011, 2010 and 2009, respectively.

        Under the Gramm-Leach-Bliley Act of 1999 ("GLBA"), effective March 11, 2000, banks, securities firms and insurance companies may affiliate under an entity known as a financial holding company which may then serve its customers' varied financial needs through a single corporate structure. GLBA has significantly changed the competitive environment in which the Company and its subsidiaries conduct business. The financial services industry is also likely to become even more competitive as further technological advances enable more companies to provide financial services. These technological advances may diminish the importance of depository institutions and other financial intermediaries in the transfer of funds between parties.

Supervision and Regulation

        GENERAL—THE COMPANY. In addition to the generally applicable state and Federal laws governing businesses and employers, the Company and its bank subsidiaries are further extensively

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regulated by special Federal and state laws governing financial institutions. These laws comprehensively regulate the operations of the Company's bank subsidiaries and include, among other matters, requirements to maintain reserves against deposits; restrictions on the nature and amount of loans that may be made and the interest that may be charged thereon; restrictions on the amounts, terms and conditions of loans to directors, officers, large shareholders and their affiliates; restrictions related to investments in activities other than banking; and minimum capital requirements. The descriptions are qualified in their entirety by reference to the full text of the applicable statutes, regulations and policies. With few exceptions, state and Federal banking laws have as their principal objective either the maintenance of the safety and soundness of the Federal deposit insurance system or the protection of consumers, rather than the specific protection of shareholders of the Company. Further, the earnings of the Company are affected by the fiscal and monetary policies of the Federal Reserve System ("FRB"), which regulates the national money supply in order to mitigate recessionary and inflationary pressures. These monetary policies influence to a significant extent the overall growth of bank loans, investments and deposits and the interest rates charged on loans or paid on time and savings deposits. The nature of future monetary policies and the effect of such policies on the future earnings and business of the Company cannot be predicted.

The Dodd-Frank Act

        On July 21, 2010, sweeping financial regulatory reform legislation entitled the "Dodd-Frank Wall Street Reform and Consumer Protection Act" (the "Dodd-Frank Act") was signed into law. The Dodd-Frank Act implements far-reaching changes across the financial regulatory landscape, including provisions that, among other things, will:

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Centralize responsibility for consumer financial protection by creating a new agency, the Bureau of Consumer Financial Protection (the "CFPB"), responsible for implementing, examining and enforcing compliance with federal consumer financial laws.



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Restrict the preemption of state law by federal law and disallow subsidiaries and affiliates of banks from availing themselves of such preemption.



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Apply the same leverage and risk-based capital requirements that apply to insured depository institutions to most bank holding companies.



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Require each federal bank regulatory agency to seek to make its capital requirement for banks countercyclical so that capital requirements increase in times of economic expansion and decrease in times of economic contraction.



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Require financial holding companies, such as the Company, to be well-capitalized and well-managed. Bank holding companies and banks must also be well-capitalized and well-managed in order to acquire banks located outside their home state.



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Change the assessment base for federal deposit insurance from the amount of insured deposits to consolidated assets less tangible capital, eliminate the ceiling on the size of the Deposit Insurance Fund ("DIF") and increase the floor of the size of the DIF.



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Impose comprehensive regulation of over-the-counter derivatives market, which would include certain provisions that would effectively prohibit insured depository institutions from conducting certain derivatives businesses in the institution itself.



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Require publicly-traded bank holding companies with $10 billion in assets or more, like the Company, to create a risk committee responsible for the oversight of risk management of the enterprise.



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Require stress testing of certain financial institutions. On June 15, 2011, the FRB published for comment proposed guidance ("Stress Testing Guidance Proposal") that would require bank holding

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companies with over $10 billion in total consolidated assets to conduct stress testing as a part of overall institution risk management. The Stress Testing Guidance Proposal includes stress testing capital and non-capital related aspects of financial condition, provides an overview of how a banking organization should develop a structure for stress testing, outlines general principles for a satisfactory stress testing framework, and describes how stress testing should be used at various levels within a banking organization. The Stress Testing Guidance Proposal also discusses the importance of stress testing in liquidity planning and the importance of strong internal governance and controls in an effective stress-testing framework. The Company does currently have total consolidated assets in excess of $10 billion and the Company would be required to conduct the stress testing described in the Stress Testing Guidance Proposal when it is effective. On January 17, 2012, the FDIC issued a similar proposal that would require state nonmember banks with over $10 billion in assets to conduct annual stress tests, report the results to the FDIC, and make the results available to the public. At this time, none of the subsidiary banks of the Company would meet the $10 billion asset threshold to be required to conduct the bank stress tests under the FDIC Proposal.

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Implement corporate governance revisions, including executive compensation and proxy access by shareholders that apply to all public companies, not just financial institutions.



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Make permanent the $250,000 limit for federal deposit insurance and increase the cash limit of Securities Investor Protection Corporation protection from $100,000 to $250,000 and provide unlimited federal deposit insurance until December 31, 2012 for non-interest bearing demand transaction accounts at all insured depository institutions.



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Repeal the federal prohibitions on the payment of interest on demand deposits, thereby permitting depository institutions to pay interest on business transaction and other accounts. In July 2011, the FRB issued a final rule, effective July 21, 2011, repealing Regulation Q, which had prohibited the payment of interest on demand deposits.



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Amend the Electronic Fund Transfer Act ("EFTA") to, among other things, give the FRB the authority to establish rules regarding interchange fees charged for electronic debit transactions by payment card issuers having assets over $10 billion and to enforce a new statutory requirement that such fees be reasonable and proportional to the actual cost of a transaction to the issuer. In June 2011,the FRB issued a final rule, effective October 1, 2011, which established the maximum permissible interchange fee that an issuer may receive for an electronic debit transaction at 21 cents per transaction and 5 basis points multiplied by the value of the transaction. The FRB also approved an interim final rule that allows for an upward adjustment of no more than 1 cent to an issuer's debit card interchange fee if the issuer develops and implements appropriate fraud-prevention policies and procedures.



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Increase the authority of the FRB to examine the Company and its non-bank subsidiaries.



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Permit interstate de novo branching without the need to acquire an existing bank.



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Require extensive new restrictions and requirements relating to residential mortgage transactions.



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Eliminate the use of credit ratings in bank regulations, including capital regulations. On November 18, 2011, the OCC proposed guidance on due diligence requirements in determining whether investment securities are eligible for investment and on January 11, 2012, the FDIC and the other Federal bank agencies proposed a rule to modify the agencies' market risk capital rules by incorporating into the rules various alternatives and complex methodologies for calculating specific risk capital requirements for debt and securitization positions that do not rely on credit ratings.



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Establish a Whistleblower Incentives and Protection Program for public company employees. On May 25, 2011, the SEC approved final rules whereby whistleblowers may receive 10% to 30% of the

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SEC-levied sanctions when a whistleblower voluntarily provides original information to the SEC and the sanctions levied against the culpable party exceed $1 million in an enforcement proceeding.

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Requires 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 (defined as hedge funds and private equity funds). The statutory provision is commonly called the "Volcker Rule." In October 2011, federal regulators proposed rules to implement the Volcker Rule that included an extensive request for comments on the proposal, which are due by February 13, 2012. 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 its subsidiaries, as the Company does not engage in the businesses prohibited by the Volcker Rule. Until a final rule is adopted, the actual financial impact of the rule on the Company, its customers or the financial industry more generally, cannot be determined.



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Authorizes the Federal Reserve Board to adopt enhanced supervision and prudential standards generally for bank holding companies with total consolidated assets of $50 billion or more (often referred to as "systemically important financial institutions" or "SIFI"), and authorizes the FRB to establish such standards either on its own or upon the recommendations of the Financial Stability Oversight Council ("FSOC"), a new systemic risk oversight body created by Dodd-Frank. The FSOC has the authority to veto a financial rule of the CFPB if the rule would threaten the safety and soundness of the entire U.S. banking system. In December 2011, the FRB issued for public comment a notice of proposed rulemaking establishing such enhanced supervision and prudential standards. Most of the proposed SIFI rules will not apply to the Company because the Company has total consolidated assets in an amount less than $50 billion. Two aspects of the proposed SIFI rules—requirements for annual stress testing of capital and certain corporate governance provisions requiring, among other things, that each bank holding company establish a risk committee of its board of directors, apply to bank holding companies with total consolidated assets of $10 billion or more, including the Company.

        Many aspects of the Dodd-Frank Act are subject to rulemaking and will take effect over several years making it difficult to anticipate the overall financial impact on the Company, its customers or the financial industry more generally. Provisions in the legislation that affect deposit insurance assessments, payment of interest on demand deposits and interchange fees are likely to increase the costs associated with deposits as well as place limitations on certain revenues those deposits may generate. Provisions in the legislation that require revisions to the capital requirements of the Company could require the Company to seek other sources of capital in the future. Some of the rules that have been adopted or proposed to comply with the Dodd-Frank Act are discussed further below.

        EMERGENCY ECONOMIC STABILIZATION ACT.    On October 3, 2008, the President signed into law the Emergency Economic Stabilization Act of 2008 or ("EESA"), which, among other measures, authorized the Secretary of the Treasury to establish the Troubled Asset Relief Program ("TARP"). Pursuant to TARP, the U.S. Treasury has the authority to, among other things, purchase up to $700 billion of mortgages, mortgage-backed securities and certain other financial instruments from financial institutions for the purpose of stabilizing and providing liquidity to the U.S. financial markets. In addition, under TARP, the Treasury created a capital purchase program ("CPP"), pursuant to which it provides access to capital that will serve as Tier 1 capital to financial institutions through a standardized program to acquire preferred stock (accompanied by warrants) from eligible financial institutions. On December 23, 2008, the Company sold $216 million of Series A Preferred Stock to the Treasury under the CPP. On February 17, 2009, President Obama signed into law the American Recovery and Reinvestment Act of 2009 (the "ARRA"). ARRA was intended to provide a stimulus to the U.S. economy in the wake of the economic downturn brought about by the subprime mortgage crisis and the resulting credit crunch. ARRA includes federal tax cuts, expansion of unemployment benefits and other social welfare provisions, and

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domestic spending in education, healthcare, and infrastructure, including the energy structure. ARRA also includes numerous non-economic recovery related items, including a limitation on executive compensation of certain of the most highly-compensated employees and executive officers of financial institutions, such as the Company, that participated in the TARP Capital Purchase Program. The restrictions in ARRA, include the following:

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Limits on compensation incentives for risk taking by senior executive officers.



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Requirement of recovery of any compensation paid based on inaccurate financial information.



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Prohibition on "Golden Parachute Payments."



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Prohibition on compensation plans that would encourage manipulation of reported earnings to enhance the compensation of employees.



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Publicly registered CPP recipients must establish a board compensation committee comprised entirely of independent directors, for the purpose of reviewing employee compensation plans.



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Prohibition on bonus, retention award, or incentive compensation, except for limited payments of long term restricted stock units payable in stock or cash.



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Limitation on luxury expenditures.



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CPP recipients are required to permit a separate non-binding shareholder vote to approve the compensation of executives, as disclosed pursuant to the SEC's compensation disclosure rules.



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The chief executive officer and chief financial officer of each CPP recipient will be required to provide a written certification of compliance with these standards to the SEC.

        Pursuant to the ARRA, subject to consultation with the appropriate Federal banking agency, the Treasury Secretary will permit a CPP participant to repay the CPP funds that they received without regard to whether the financial institution has replaced such funds from any other source, and when such CPP funds are repaid, the Treasury Secretary will liquidate warrants associated with the CPP funds at the current market price, however, in certain instances the determination of the market price of the warrants has taken considerable time.

        FRB APPROVALS.    The Company is a registered bank holding company within the meaning of the BHCA, and is subject to supervision by the FRB and to a certain extent the Texas Department of Banking (the "DOB"). The Company is required to file with the FRB annual reports and other information regarding the business operations of itself and its subsidiaries. It is also subject to examination by the FRB. Under the BHCA, a bank holding company is, with limited exceptions, prohibited from acquiring direct or indirect ownership or control of any voting stock of any company which is not a bank or bank holding company, and must engage only in the business of banking, managing, controlling banks, and furnishing services to or performing services for its subsidiary banks. One of the exceptions to this prohibition is the ownership of shares of any company provided such shares do not constitute more than 5% of the outstanding voting shares of the company and so long as the FRB does not disapprove such ownership. Another exception to this prohibition is the ownership of shares of a company the activities of which the FRB has specifically determined to be so closely related to banking, managing or controlling banks as to be a proper incident thereto.

        The BHCA and the Change in Bank Control Act of 1978 require that, depending on the circumstances, either FRB approval must be obtained or notice must be furnished to the FRB and not disapproved prior to any person or company acquiring "control" of a bank holding company, such as the Company, subject to certain exceptions for certain transactions. Control is conclusively presumed to exist if an individual or company acquires 25% or more of any class of voting securities of the bank holding company. Control is rebuttably presumed to exist if a person acquires 10% or more but less than 25% of any class of voting securities where the bank holding company, such as the Company, has registered Securities under Section 12 of the Securities Exchange Act of 1934 (the "Exchange Act").

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        As a bank holding company, the Company is required to obtain approval prior to merging or consolidating with any other bank holding company, acquiring all or substantially all of the assets of any bank or acquiring ownership or control of shares of a bank or bank holding company if, after the acquisition, the Company would directly or indirectly own or control 5% or more of the voting shares of such bank or bank holding company.

        THE USA PATRIOT ACT.    Combating money laundering and terrorist financing is a major focus of financial institution regulatory policy. The USA PATRIOT Act of 2001 substantially expanded the responsibilities of U.S. financial institutions with respect to countering money laundering and terrorist activities. The implementing 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. Also, the USA PATRIOT Act requires the bank regulatory agencies to consider the record of a bank or bank holding company in combating money laundering activities in their evaluation of bank and bank holding company merger or acquisition transactions. The Company has a program in place to monitor and enforce its policies on money laundering, corruption and bribery as well as its policies on prohibiting the use of Company assets to finance or otherwise aid alleged terrorist groups. Failure of a financial institution to maintain and implement adequate programs to combat money laundering and terrorist financing, or to comply with all the relevant laws or regulations, could have serious legal and reputational consequences for the institution.

        NONRESIDENT ALIEN DEPOSITS.    In January 2011, the IRS published a notice of proposed rulemaking to provide guidance on the reporting requirements for interest on deposits paid to nonresident alien individuals. Rules currently in effect require reporting of U.S. bank deposit interest only if the interest is paid to a U.S. person or nonresident alien individual who is a resident of Canada. The proposed rule, however, would extend the reporting requirements to include bank deposit interest paid to nonresident alien individuals who are residents of any foreign country. If the proposed rule is adopted, it could lead to deposit withdrawals by individuals who were not previously subject to the reporting requirement.

        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 take many forms, including without limitation, restrictions on trade or investment and the blocking of certain assets related to the designated foreign countries and nationals. Blocked assets, which may include bank deposits, cannot be paid out, withdrawn, set off or transferred in any manner without a license from OFAC. Failure to comply with the OFAC sanctions could have serious legal and reputational consequences.

        GRAMM-LEACH-BLILEY.    The Gramm-Leach-Bliley Act of 1999 ("GLBA") eliminates the barriers to affiliations among banks, securities firms, insurance companies and other financial service providers. GLBA provides for a new type of financial holding company structure under which affiliations among these entities may occur. Under GLBA, a financial holding company may engage in a broad list of financial activities and any non-financial activity that the FRB determines is complementary to a financial activity and poses no substantial risk to the safety and soundness of depository institutions or the financial system. In addition, GLBA permitted certain non-banking financial and financially related activities to be conducted by financial subsidiaries of banks.

        Under GLBA, a bank holding company may become certified as a financial holding company by filing a declaration with the FRB, together with a certification that each of its subsidiary banks is well capitalized, is well managed, and has at least a satisfactory rating under the Community Reinvestment Act of 1977 ("CRA"). The Company has elected to become a financial holding company under GLBA and the election was made effective by the FRB as of March 13, 2000. During the second quarter of 2000, IBC established an insurance agency subsidiary which acquired two insurance agencies. As part of the Local

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Financial Corporation ("LFIN") acquisition in 2004, the Company acquired a securities firm registered under the Exchange Act, IBC Investments, Inc. A financial holding company that has a securities affiliate registered under the Act or a qualified insurance affiliate may make permissible merchant banking investments. As of December 31, 2011, the Company has made 32 merchant banking investments. The Dodd-Frank Act requires that bank holding companies must be "well-capitalized" and "well-managed" in order to engage in the expanded financial activities permissible for financial holding companies under GLBA.

        The FRB and the Secretary of the Treasury have regulations governing the scope of permissible merchant banking investments. The investments that may be made under this authority are substantially broader in scope than the investment activities otherwise permissible for bank holding companies, and are referred to as "merchant banking investments" in "portfolio companies." Before making a merchant banking investment, a financial holding company must either be or have a securities affiliate registered under the Exchange Act or a qualified insurance affiliate. The merchant banking investments may be made by the financial holding company or any of its subsidiaries, other than a depository institution or subsidiary of a depository institution. The regulations place restrictions on the ability of a financial holding company to become involved in the routine management or operation of any of its portfolio companies. The regulation also generally limits the ownership period of merchant banking investments to no more than ten years.

        The FRB, the Office of the Comptroller of the Currency (the "OCC"), and the FDIC have rules governing the regulatory capital treatment of equity investments in non-financial companies held by banks, bank holding companies and financial holding companies. The rule applies a graduated capital charge on covered equity investments which would increase as the proportion of such investments to Tier 1 Capital increases.

        PREEMPTION.    At the beginning of 2004, the OCC issued final rules clarifying when federal law overrides state law for national banks and their operating subsidiaries and confirming that only the OCC has the right to examine and take enforcement action against those institutions. However, the Dodd-Frank Act limits the applicability of the preemption doctrine so that state laws affecting national banks are preempted only in certain circumstances. In May 2011, the OCC first proposed new regulations to implement the Dodd-Frank Act's preemption provision. In proposing those regulations, the OCC stated that its preemption formula—"obstruct, impair, or condition"—had "created ambiguities and misunderstandings" and would therefore be removed from the regulations. Nevertheless, the OCC concluded that its formula was "drawn from an amalgam of prior precedents relied upon" in Barnett Bank, and was therefore consistent with Barnett Bank itself. The OCC further opined that while the Dodd-Frank Act had extracted from Barnett Banka specific formulation of the conflict preemption standard—the "prevents or significantly interferes with" formulation discussed above—that is "not the only formulation" in Barnett Bank, and Barnett Bank did not "present it as a test different from" the other formulations in the opinion. Thus, the OCC chose not to incorporate the specific Barnett Bank formulation used in the Dodd-Frank Act's preemption provision into its new proposed regulations implementing that provision. Comments to the proposed regulations were due June 27, 2011, but a definitive final rule has not been issued.

        FINANCIAL PRIVACY.    The federal banking regulators adopted rules that limit the ability of banks and other financial institutions to disclose non-public information about consumers to non-affiliated third parties. Pursuant to the rules, financial institutions must provide disclosure of privacy policies to consumers and in some instances allow consumers to prevent disclosure of certain personal information to a nonaffiliated third party. These privacy provisions affect how customer information is transmitted through diversified financial companies and conveyed to outside vendors.

        NASDAQ LISTING STANDARDS.    The Company is traded on the NASDAQ Stock Market. The Company must comply with the listing standards of the NASDAQ Stock Market. In addition to other

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matters, the listing standards address disclosure requirements and standards relating to board independence and other corporate governance matters.

        INTERSTATE BANKING.    The Riegle-Neal Interstate Banking and Branching Efficiency Act of 1994 ("Interstate Banking Act"), rewrote federal law governing the interstate expansion of banks in the United States. Under the Interstate Banking Act, adequately capitalized, well managed bank holding companies with FRB approval may acquire banks located in any State in the United States, provided that the target bank meets the minimum age (up to a maximum of five years, which is the maximum Texas has adopted) established by the host State. Under the Interstate Banking Act, an anti-concentration limit will bar interstate acquisitions that would give a bank holding company control of more than ten percent (10%) of all deposits nationwide or thirty percent (30%) of any one State's deposits, or such higher or lower percentage established by the host State. The anti-concentration limit in Texas has been set at twenty percent (20%) of all federally insured deposits in Texas. As allowed by the Interstate Banking Act, the Company acquired LFIN, including its Oklahoma financial institution, during 2004. The Dodd-Frank Act changes the requirements for interstate branching by permitting de novo interstate branching if, under the laws of the state where the new branch is to be established, a state bank chartered in that state would be permitted to establish a branch.

        FRB ENFORCEMENT POWERS.    The FRB has certain cease-and-desist and divestiture powers over bank holding companies and non-banking subsidiaries where their actions would constitute a serious threat to the safety, soundness or stability of a subsidiary bank. These powers may be exercised through the issuance of cease-and-desist orders or other actions. In the event a bank subsidiary experiences either a significant loan loss or rapid growth of loans or deposits, the Company may be compelled by the FRB to invest additional capital in the bank subsidiary. Further, the Company would be required to guaranty performance of the capital restoration plan of any undercapitalized bank subsidiary. The FRB is also empowered to assess civil money penalties against companies or individuals who violate the BHCA in amounts up to $1,000,000 per day, to order termination of non-banking activities of non-banking subsidiaries of bank holding companies and to order termination of ownership and control of a non-banking subsidiary. Under certain circumstances the Texas Banking Commissioner may bring enforcement proceedings against a bank holding company in Texas.

        COMPANY DIVIDENDS.    The Company is subject to regulatory policies and requirements relating to the payment of dividends, including requirements to maintain adequate capital above regulatory minimums. The FRB is authorized to determine under certain circumstances relating to the financial condition of a bank holding company, that the payment of dividends would be an unsafe or unsound practice and to prohibit payment thereof. In addition, in the current financial and economic environment, the FRB has indicated that bank holding companies should carefully review their dividend policy and has discouraged payment ratios that are at maximum allowable levels unless both asset quality and capital are very strong.

        CROSS-GUARANTEE PROVISIONS.    The Financial Institutions Reform Recovery and Enforcement Act of 1989 ("FIRREA") contains a "cross-guarantee" provision which generally makes commonly controlled insured depository institutions liable to the FDIC for any losses incurred in connection with the failure of a commonly controlled depository institution.

        SOURCE OF STRENGTH DOCTRINE.    FRB policy has historically required bank holding companies to act as a source of financial and managerial strength to their subsidiary banks. The Dodd-Frank Act codifies this policy as a statutory requirement and the FRB is expected to issue new regulations by July 21, 2012, implementing the Dodd-Frank Act source of strength provision. Under this requirement, the Company is expected to commit resources to support its subsidiary banks, including 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. In the event of a bank holding Company's

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bankruptcy, any commitment by the bank holding company to a federal bank regulatory agency to maintain the capital of a subsidiary bank will be assumed by the bankruptcy trustee and entitled to priority of payment.

        GENERAL—BANK SUBSIDIARIES.    All of the bank subsidiaries of the Company are state banks subject to regulation by, and supervision of, the Texas DOB and the FDIC.

        DEPOSIT INSURANCE.    All of the bank subsidiaries of the Company are examined by the FDIC, which currently insures the deposits of each member bank up to applicable limits. Deposits of each of the bank subsidiaries are insured by the FDIC through the DIF to the extent provided by law. The FDIC uses a risk-based assessment system that imposes premiums based upon a matrix that takes into account a bank's capital level and supervisory rating. As of January 1, 2007, the previous nine risk categories utilized in the risk matrix were condensed into four risk categories which continue to be distinguished by capital levels and supervisory ratings. During 2007, the bank subsidiaries of the Company were required to pay deposit insurance premiums. Under the Federal Deposit Insurance Reform Act of 2005, which became law in 2006, the bank subsidiaries of the Company received a one-time assessment credit that can be applied against future premiums, subject to certain limitations. During 2009, the remaining credit was used to offset a portion of the deposit insurance premiums owed by the bank subsidiaries of the Company. During 2009, the bank subsidiaries of the Company paid Financing Corporation ("FICO") assessments related to outstanding FICO bonds to the FDIC as a collection agent. The FICO is a mixed-ownership government corporation whose sole purpose was to serve as a financing vehicle for the defunct Federal Savings & Loan Insurance Corporation.

        In December 2008, the FDIC issued a final rule that raised the then current assessment rates uniformly by 7 basis points for the first quarter of 2009 assessment, which resulted in annualized assessment rates for institutions, such as the subsidiary banks in Risk Category 1 ("Risk Category 1 institutions"), ranging from 12 to 14 basis points (basis points representing cents per $100 of assessable deposits). In February 2009, the FDIC issued final rules to amend the DIF restoration plan, change the risk-based assessment system and set assessment rates for Risk Category 1 institutions beginning in the second quarter of 2009. The initial base assessment rates for Risk Category 1 institutions range from 12 to 16 basis points, on an annualized basis. After the effect of potential base-rate adjustments, total base assessment rates rate from 7 to 24 basis points.

        In May 2009, the FDIC issued a final rule which levied a special assessment applicable to all insured depository institutions totaling 5 basis points of each institution's total assets, less Tier 1 capital, as of June 30, 2009, not to exceed 10 basis points of domestic deposits. The special assessment was part of the FDIC's efforts to rebuild the DIF. Deposit insurance expenses for the Subsidiary Banks during 2009 included $5.1 million accrued in the second quarter related to the special assessment.

        In November 2009, the FDIC issued a rule that required all deposit 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, 2011, $20.2 million in pre-paid risk-based assessments is included in other assets in the accompanying consolidated balance sheet.

        In October 2010, the FDIC adopted a new DIF restoration plan to ensure that the fund reserve ratio reaches 1.35% by September 30, 2020, as required by the Dodd-Frank Act. Under the new restoration plan, the FDIC will forego the uniform three-basis point increase in initial assessment rates scheduled to take place on January 1, 2011, and maintain the current schedule of assessment rates for all depository institutions. At least semi-annually, the FDIC will update its loss and income projections for the fund and, if needed, will increase or decrease assessment rates, following notice-and-comment rulemaking if required.

        In November 2010, the FDIC issued a final rule to implement provisions of the Dodd-Frank Act that provide for temporary unlimited coverage for non-interest bearing transaction accounts. The separate

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coverage for non-interest bearing transaction accounts became effective on December 31, 2010 and terminates on December 31, 2012.

        In February 2011, the FDIC issued a final rule effective April 1, 2011 that set a target size for the insurance fund and changed the deposit insurance assessment base from total domestic deposits to average total assets minus average tangible equity, as required by the Dodd-Frank Act. The rule finalizes a target size for the DIF at 2 percent of insured deposits. It also implements a lower assessment rate schedule when the fund reaches 1.15 percent and, in lieu of dividends, provides for a lower rate schedule when the reserve ratio reaches 2 percent and 2.5 percent. The final rule creates a risk-based scorecard assessment system for banks with more than $10 billion in assets. The scorecards include financial measures that the FDIC believes are predictive of long-term performance. While the April 1, 2011 final rule is expected to be revenue neutral, it is possible that the rule will change the Company's overall FDIC assessment. In September 2011, the FDIC issued new guidelines that reflect the methodology it now uses to determine assessment rates for large and highly complex institutions. A "large institution" is defined as an insured depository institution with assets of $10 billion or more, and a "highly complex institution" is defined as an insured depository institution with assets of $50 billion or more. Total scores are determined according to the April 1, 2011 final rule. While IBC does not currently meet the definition of a large institution under the new guidelines, the Company cannot provide any assurance as to the effect of any further change in its deposit insurance premium rate, should such a change occur, as such changes are dependent upon a variety of factors, some of which are beyond the Company's control.

        Under the FDIA, the FDIC may terminate deposit insurance upon a finding that the institution has engaged in unsafe and unsound practices, is in an unsafe or uninsured condition to continue operations, or has violated any applicable law, regulation, rule or order of condition imposed by the FDIC.

        CAPITAL ADEQUACY.    The Company and its bank subsidiaries are currently required to meet certain minimum regulatory capital guidelines utilizing total capital-to-risk-weighted assets and Tier 1 Capital elements. The guidelines make regulatory capital requirements more sensitive to differences in risk profiles among banking organizations, consider off-balance sheet exposure in assessing capital adequacy, and encourage the holding of liquid, low-risk assets. At least one-half of the minimum total capital must be comprised of Core Capital or Tier 1 Capital elements. Tier 1 Capital of the Company is comprised of common shareholders' equity and permissible amounts related to the trust preferred securities. The deductible core deposit intangibles and goodwill booked in connection with all the financial institution acquisitions of the Company after February 1992 are deducted from the sum of core capital elements when determining the capital ratios of the Company.

        In addition, the FRB has established minimum leverage ratio guidelines for bank holding companies. These guidelines provide for a minimum leverage ratio of Tier 1 capital to adjusted average quarterly assets ("leverage ratio") equal to three percent for bank holding companies that meet certain specified criteria, including having the highest regulatory rating. All other bank holding companies will generally be required to maintain a leverage ratio of at least four to five percent. The Company's leverage ratio at December 31, 2011 was 12.74%. The guidelines also provide that bank holding companies 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. Furthermore, the guidelines indicate that the FRB will continue to consider a "tangible tier 1 leverage ratio" (deducting all intangibles) in evaluating proposals for expansion or new activity. The FRB has not advised the Company of any specific minimum leverage ratio or tangible Tier 1 leverage ratio applicable to it. For a bank holding company to be considered "well-capitalized" under the regulatory framework for prompt corrective action, its leverage ratio must be at least 5.0%.

        Each of the Company's bank subsidiaries is subject to similar capital requirements adopted by the FDIC. Each of the Company's bank subsidiaries had a leverage ratio in excess of five percent as of

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December 31, 2011. As of that date, the federal banking agencies had not advised any of the bank subsidiaries of any specific minimum leverage ratio applicable to it.

        In March 2005, the FRB issued a final rule that would continue to allow the inclusion of trust preferred securities in Tier 1 capital, but with stricter quantitative limits. Under the final rule, after a five-year transition period ending March 31, 2009, the aggregate amount of trust preferred securities and certain other capital elements would be limited to 25% of Tier 1 capital elements, net of goodwill, less any associated deferred tax liability. The amount of trust preferred securities and certain other elements in excess of the limit could be included in Supplementary Capital or Tier 2 capital, subject to restrictions. Tier 2 capital includes among other things, perpetual preferred stock, qualifying mandatory convertible debt securities, qualifying subordinated debt, and allowances for probable loan and lease losses, subject to limitations. Bank holding companies with significant international operations will be expected to limit trust preferred securities to 15% of Tier 1 capital elements, net of goodwill; however, they may include qualifying mandatory convertible preferred securities up to the 25% limit. On March 16, 2009, the FRB extended for two years the transition period. Substantially all of the trust preferred securities issued by the Company qualified as Tier 1 capital after the transition period ended on March 31, 2011. The Collins Amendment to the Dodd-Frank Act further restricts the use of trust preferred securities by excluding them from the regulatory capital of banking holding companies more broadly. However, for institutions with consolidated assets of less than $15 billion on December 31, 2009, such as the Company, the Collins Amendment will not apply to securities issued before May 19, 2010 and all the Company's trust preferred securities were issued before such date.

        Effective December 19, 1992, the federal bank regulatory agencies adopted regulations which mandate a five-tier scheme of capital requirements and corresponding supervisory actions to implement the prompt corrective action provisions of FDICIA. The regulations include requirements for the capital categories that will serve as benchmarks for mandatory supervisory actions. Under the regulations, the highest of the five categories would be a well capitalized institution with a total risk-based capital ratio of 10%, a Tier 1 risk-based capital ratio of 6% and a Tier 1 leverage ratio of 5%. An institution would be prohibited from declaring any dividends, making any other capital distribution or paying a management fee if the capital ratios drop below the levels for an adequately capitalized institution, which are 8%, 4% and 4%, respectively. The corresponding provisions of FDICIA mandate corrective actions are taken if a bank is undercapitalized. Based on the Company's and each of the bank subsidiaries' capital ratios as of December 31, 2011, the Company and each of the bank subsidiaries were classified as "well capitalized" under the applicable regulations.

        The risk-based standards that apply to bank holding companies and banks incorporate market and interest rate risk components. Applicable banking institutions are required to adjust their risk-based capital ratio to reflect market risk. Under the market risk capital guidelines, capital is allocated to support the amount of market risk related to a financial institution's ongoing trading activities. Financial institutions are allowed to issue qualifying unsecured subordinated debt (Tier 3 capital) to meet a part of their market risks. The Company does not have any Tier 3 capital and did not need Tier 3 capital to offset market risks. In January 2010, the federal bank regulators issued a final risk-based capital rule related to new accounting standards that make substantive changes in how banking organizations account for more items, including securitized assets that previously had been taken off banks' balance sheets. Dodd-Frank directs the banking agencies to issue capital requirements for banking institutions that are countercyclical. These will require a higher level of capital to be maintained in times of economic expansion and a lower level of capital during times of economic contraction.

        The federal regulatory authorities' risk-based capital guidelines are based upon the 1988 capital accord of the Basel Committee on Banking Supervision (the "BIS"). The BIS is a committee of central banks and bank supervisors/regulators from the major industrialized countries that develops broad policy guidelines for use by each country's supervisors in determining the supervisory policies they apply. In June 2004, the BIS released a new capital accord to replace the 1988 capital accord with an update in

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November 2005 ("BIS II"). BIS II would set capital requirements for operational risk, and refine the existing capital requirements for credit risk and market risk exposures. The United States federal banking agencies are developing proposed revisions to their existing capital adequacy regulations and standards based on BIS II. A definitive final rule for implementing BIS II in the United States that would apply only to internationally active banking organizations, or "core banks"—defined as those with consolidated total assets of $250 billion or more or consolidated on-balance sheet foreign exposures of $10 billion or more became effective as of April 1, 2008. Other U.S. banking organizations may elect to adopt the requirements of this rule (if they meet applicable qualification requirements), but they will not be required to apply them. The rule also allows a banking organization's primary federal supervisor to determine that the application of the rule would not be appropriate in light of the bank's asset size, level of complexity, risk profile, or scope of operations. The Company is not required to comply with BIS II at this time.

        In July 2008, the banking agencies issued a proposed rule that would give banking organizations that are not required to comply with Basel II the option to implement a new risk-based capital framework. This framework would adopt the standardized approach of Basel II for credit risk, the basic indicator approach of Basel II for operational risk, and related disclosure requirements. While this proposed rule generally parallels the relevant approaches under Basel II, it diverges where United States markets have unique characteristics and risk profiles, most notably with respect to risk weighting residential mortgage exposures. Comments on the proposed rule were due to the agencies by October 27, 2008, but a definitive final rule has not been issued.

        The Dodd-Frank Act requires the FRB, the OCC and the FDIC to adopt regulations imposing a continuing "floor" of the BIS risk-based capital requirements in cases where the BIS risk-based capital requirements and any changes in capital regulations resulting from Basel-III (see below) otherwise would permit lower requirements. In December 2010, the FRB, the OCC and the FDIC issued a joint notice of proposed rulemaking that would implement this requirement. On June 24, 2011, the agencies approved this rule in final form and it became effective on July 28, 2011.

        In December 2010, the Basel Committee released its final framework for strengthening international capital and liquidity regulation, now officially identified by the Basel Committee as "Basel III." Basel III, when implemented by the U.S. banking agencies and fully phased-in, will require bank holding companies and their bank subsidiaries to maintain substantially more capital, with a greater emphasis on common equity.

        The Basel III final capital framework, among other things, (i) introduces as 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 adjustments to regulatory capital measures be made to CET1 and not to the other components of capital and (iv) expands the scope of the adjustments as compared to existing regulations.

        Basel III also provides for a "countercyclical capital buffer," generally to be imposed when national regulators determine that excess aggregate credit growth becomes associated with a buildup of systemic risk. The capital conservation buffer is designed to absorb losses during periods of economic stress. Banking institutions with a ratio of CET1 to risk-weighted assets above the minimum but below the conservation buffer will face constraints on dividends, equity repurchases and compensation based on the amount of the shortfall. Notwithstanding its release of the Basel III framework as a final framework, the Basel Committee is considering further amendments to Basel III, including the imposition of additional capital surcharges on globally systemically important financial institutions.

        In addition to Basel III, the Dodd-Frank Act requires or permits the Federal banking agencies to adopt regulations affecting banking institutions' capital requirements in a number of respects, including potentially more stringent capital requirements for systemically important financial institutions. In January 2011, the FRB, OCC and FDIC requested comment on a proposal to implement various revisions to the market risk framework adopted by the Basel Committee between July 2005 and June 2010. The revisions

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would significantly modify the agencies' market risk capital rules to better capture those positions for which application of the market risk capital rules are appropriate, address shortcomings in the modeling of certain risks, address procyclicality concerns, enhance the rules' sensitivity to risks that are not adequately captured under the current regulatory capital measurement methodologies, and increase transparency through enhanced disclosures.

        The January 2011 proposal did not include the methodologies adopted by the Basel Committee for calculating the standard specific risk capital requirements for certain debt and securitization positions, because the BCBS methodologies generally rely on credit ratings. Under section 939A of the Dodd-Frank Act, all federal agencies must remove references to and requirements of reliance on credit ratings from their regulations and replace them with appropriate alternatives for evaluating creditworthiness. Accordingly, in November 2011, the agencies proposed to incorporate into the proposed market risk capital rules certain alternative methodologies for calculating specific risk capital requirements for debt and securitization positions that do not rely on credit ratings. The agencies expect to finalize this proposal, together with the January 2011 proposal, in 2012 after receipt and consideration of comments. In November 2011, the OCC requested comment on proposed guidance on due diligence requirements in determining whether investment securities are eligible for investment. The OCC proposal is expected to influence the FDIC's treatment of due diligence for state-chartered nonmember banks, such as the IBC bank subsidiaries. The proposed guidance greatly complicates the due diligence that financial institutions must conduct on securities prior to purchasing the securities due to the inability of financial institutions to rely on credit ratings. The due diligence requirement could result in significant additional costs to financial institutions.

        Accordingly, the regulations ultimately applicable to the Company may be substantially different from the Basel III final framework as published in December 2010. Requirements to maintain higher levels of capital or to maintain higher levels of liquid assets could adversely impact the Company's net income and return on equity.

        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 final 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, going forward will be required by regulation. These new standards are subject to further rulemaking and their terms may well change before implementation.

        STATE ENFORCEMENT POWERS.    The Banking Commissioner of Texas may determine to close a Texas state bank when he finds that the interests of depositors and creditors of a state bank are jeopardized through its insolvency or imminent insolvency and that it is in the best interest of such depositors and creditors that the bank be closed. The Texas DOB also has broad enforcement powers over the bank subsidiaries, including the power to impose orders, remove officers and directors, impose fines and appoint supervisors and conservators.

        DEPOSITOR PREFERENCE.    Because the Company is a legal entity separate and distinct from its bank 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 a subsidiary bank, the claims of depositors and other general or subordinated creditors of the bank 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.

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        CRA. Under the CRA, the FDIC is required to assess the record of each bank subsidiary to determine if the bank meets the credit needs of its entire community, including low and moderate-income neighborhoods served by the institution, and to take that record into account in its evaluation of any application made by the bank for, among other things, approval of the acquisition or establishment of a branch or other deposit facility, an office relocation, a merger, or the acquisition of shares of capital stock of another financial institution. The FDIC prepares a written evaluation of an institution's record of meeting the credit needs of its entire community and assigns a rating. The FIRREA requires federal banking agencies to make public a rating of a bank's performance under the CRA. The Company's bank subsidiaries conduct an award-winning financial literacy program in their communities as part of their community outreach. Further, there are fair lending laws, including the Equal Credit Opportunity Act and the Fair Housing Act, which prohibit discrimination in connection with lending decisions. The bank regulators periodically conduct fair lending evaluations of banks. Three of the subsidiary banks of the Company received a "Satisfactory" CRA rating in its most recently completed examination; however, in February 2011, IBC received a "Needs to Improve" CRA rating as a result of alleged fair lending issues associated with mortgage origination activities of IBC in prior years. Unless and until IBC's CRA rating improves, IBC will be ineligible for expedited treatment and is unlikely to receive approval for branch, merger, and acquisition applications and IBC and the Company will be subject to certain other regulatory limitations. Financial institutions are evaluated under different CRA examinations procedures based upon their asset-size classification, which asset thresholds are updated annually and were updated as of January 1, 2012. "large institution" now means a bank with total assets of at least $1.160 billion for December 31 of both of the prior two years and "intermediate small institution" means an institution with assets of at least $290 million and less than $1.160 billion as of December 31 of both of the prior two calendar years. Three of the Company's subsidiary banks are "intermediate small institutions" and the flagship bank is a "large institution" under the new asset thresholds.

        CONSUMER LAWS.    In addition to the laws and regulations discussed herein, the Bank is also subject to numerous consumer laws and regulations that are designed to protect consumers in transactions with banks. These laws and regulations mandate certain disclosure requirements and regulate the manner in which financial institutions must deal with customers when taking deposits or making loans to such customers. The Bank must comply with the applicable provisions of these consumer protection laws and regulations as part of their ongoing customer relations. The Dodd-Frank Act provides for comprehensive new rules regulating mortgage activities and creates the new CFPB with direct supervisory authority over banks with assets of $10 billion or more and certain nonbank entities. Authority to implement almost all federal consumer financial protection laws and regulations was transferred to the CFPB on July 21, 2011. The CFPB has broad authority, among other matters, to declare acts or practices to be "unfair, deceptive, or abusive," to develop and require new consumer disclosures, and to restrict the use of certain arbitration clauses. While the CFPB does not currently have direct supervisory authority over any of the Company's subsidiary banks because they each fall below the $10 billion assets threshold, the CFPB's broad authority to issue, interpret, and enforce almost all federal consumer protection laws and its issuance of applicable disclosure forms, will significantly impact each of the Company's subsidiary bank's consumer compliance programs. On January 20, 2012, the CFPB issued a final rule that imposes new disclosure requirements for remittance transfers which clarifies the disclosures that must be made to the consumer and gives the consumer thirty minutes after payment is made to cancel the transaction. The new rule has a one year implementation period.

        ELECTRONIC BANKING.    In 2005, the Federal Financial Institutions Examination Council (the "FFIEC") issued guidance entitled "Authentication in an Internet Banking Environment" (the "2005 Guidance"), which provided a risk management framework for financial institutions offering Internet-based products and services to their customers. It required that institutions use effective methods to authenticate the identity of customers and that the techniques employed be commensurate with the risks associated with the products and services offered and the protection of sensitive customer information. On June 29, 2011, the FDIC and the other FFIEC agencies supplemented the 2005 Guidance by specifying the

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FDIC's supervisory expectations regarding customer authentication, layered security, and other controls in an increasingly hostile online environment. The FDIC indicates that layered security controls should include processes to detect and respond to suspicious or anomalous activity and, for business accounts, administrative controls. In September 2011, the Texas Bankers Electronic Crimes Task Force, formed by the Texas Banking Commissioner and the U.S. Secret Service, issued guidance entitled "Best Practices: Reducing the Risks of Corporate Account Takeovers." In accordance with FDIC FIL-2011, this guidance sets forth nineteen best practices to reduce the risk of corporate account takeover thefts. The Company's subsidiary banks are required to comply with these guidelines and best practices.

        AFFILIATE TRANSACTIONS.    The Company, IBC and the other bank subsidiaries of the Company are "affiliates" within the meaning of Section 23A of the Federal Reserve Act which sets forth certain restrictions on loans and extensions of credit between a bank subsidiary and affiliates, on investments in an affiliate's stock or other securities, and on acceptance of such stock or other securities as collateral for loans. Such restrictions prevent a bank holding company from borrowing from any of its bank subsidiaries unless the loans are secured by specific obligations. Further, such secured loans and investments by a bank subsidiary are limited in amount, as to a bank holding company or any other affiliate, to 10% of such bank subsidiary's capital and surplus and, as to the bank holding company and its affiliates, to an aggregate of 20% of such bank subsidiary's capital and surplus. Certain restrictions do not apply to 80% or more owned sister banks of bank holding companies. Each bank subsidiary of the Company is wholly-owned by the Company. Section 23B of the Federal Reserve Act requires that the terms of affiliate transactions be comparable to terms of similar non-affiliate transactions. The Dodd-Frank Act expands the limitation on affiliate transactions, it will require that the 10% of capital limit on covered transactions begin to apply to non-bank financial subsidiaries. "Covered transactions" are defined by statute to include a loan or extension of credit, as well as a purchase of securities issued by an affiliate, a purchase of assets (unless otherwise exempted by the Federal Reserve Board) from the affiliate, the acceptance of securities issued by the affiliate as collateral for a loan, and the issuance of a guarantee, acceptance or letter of credit on behalf of an affiliate.

        INSIDER LOANS.    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. These restrictions include limits on loans to one borrower, prohibition on preferential terms, and other conditions that must be met before such a loan can be made. There is also an aggregate limitation on all loans to insiders and their related interests. These loans cannot exceed the institution's total unimpaired capital and surplus, and the FDIC may determine that a lesser amount is appropriate. Insiders are subject to enforcement actions for knowingly accepting loans in violation of applicable restrictions.

        LENDING RESTRICTIONS.    The operations of the Banks are also subject to lending limit restrictions pertaining to the extension of credit and making of loans to one borrower. Further, under the BHCA and the regulations of the FRB thereunder, the Company and its subsidiaries are prohibited from engaging in certain tie-in arrangements with respect to any extension of credit or provision of property or services; however, the FRB adopted a rule relaxing tying restrictions by permitting a bank holding company to offer a discount on products or services if a customer obtains other products or services from such company. In February 2005, the banking agencies issued best practices guidelines on overdraft protection programs which state that overdraft protection programs are an extension of credit, but are not subject to Truth-in-Lending disclosure requirements. On November 12, 2009, the FRB issued final rules amending Regulation E that prohibit financial institutions from charging consumer fees for paying overdrafts on ATM and on-time debit card transactions, unless the consumer consents or opts-in to the overdraft service for those types of transactions. In November 2010, the FDIC issued final overdraft protection guidance, effective July 1, 2011, which focuses on automated overdraft programs and encourages banks to offer less costly alternatives. Additionally, the FDIC requires banks to monitor programs for excessive or chronic customer use and to undertake meaningful and effective follow-up

22

action thereafter, institute appropriate daily limits on customer costs, consider eliminating overdraft fees for transactions that overdraw an account by a de minimis amount, ensure that transactions are not processed in a manner designed to maximize the costs to consumers, and ensure that boards of directors provide appropriate oversight of overdraft protection programs.

        DIVIDENDS.    The ability of the Company to pay dividends is largely dependent on the amount of cash derived from dividends declared by its bank subsidiaries. The payment of dividends by any bank or bank holding company is affected by the requirement to maintain adequate capital as discussed above. The ability of the Banks, as Texas banking associations, to pay dividends is restricted under Texas law. A Texas bank generally may not pay a dividend reducing its capital and surplus without the prior approval of the Texas Banking Commissioner. The FDIC has the right to prohibit the payment of dividends by a bank where the payment is deemed to be an unsafe and unsound banking practice. Additionally, as a result of the Company's participation in the CPP, the Company was restricted in the payment of dividends and was not allowed without the Treasury Department's consent to declare or pay any dividend on the Company Common Stock other than a regular semi-annual cash dividend of not more than $.33 per share, as adjusted for any stock dividend or stock split. The restriction ceased to exist on December 23, 2011. At December 31, 2011, there was an aggregate of approximately $585,000,000 available for the payment of dividends to the Company by IBC, Commerce Bank, IBC-Zapata and IBC-Brownsville under the applicable restrictions, assuming that each of such banks continues to be classified as "well capitalized." Further, the Company could expend the entire $585,000,000 and continue to be classified as "well capitalized". Note 20 of Notes to Consolidated Financial Statements of the Company in the 2011 Annual Report is incorporated herein by reference.

        POWERS.    As a result of FDICIA, the authority of the FDIC over state-chartered banks was expanded. FDICIA limits state-chartered banks to only those principal activities permissible for national banks, except for other activities specifically approved by the FDIC. The new Texas Banking Act includes a parity provision which establishes procedures for state banks to notify the Banking Commissioner if the bank intends to conduct any activity permitted for a national bank that is otherwise denied to a state bank. The Banking Commissioner has thirty (30) days to prohibit the activity. Also, the Texas Finance Code includes a super parity provision with procedures for state banks to notify the Banking Commissioner if the bank intends to conduct any activity permitted for any depository institution in the United States. The Banking Commissioner has thirty (30) days to prohibit the activity.

        INCENTIVE COMPENSATION.    In June 2010, the Federal Reserve, OCC and FDIC issued the Interagency Guidance on Sound Incentive Compensation Policies, a 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 will review, as part of the regular, risk-focused examination process, the incentive compensation arrangements of banking organizations, such as the Company. 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

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organization's safety and soundness and the organization is not taking prompt and effective measures to correct the deficiencies.

        The Dodd-Frank Act requires the federal banking agencies and the Securities and Exchange Commission to jointly prescribe regulations or guidelines that require financial institutions with $1 billion or more in assets to disclose to the appropriate federal regulator, the structure of all incentive-based compensation arrangements sufficient to determine whether the compensation structure provides an executive officer, employee, director, or principal shareholder with excessive compensation, fees, or benefits, or could lead to material financial loss to the financial institutions. On February 7, 2011, the FDIC issued a notice of proposed rulemaking that would prohibit bank incentive-based compensation arrangements that encourage inappropriate risk taking, are deemed excessive, or may lead to material losses. The proposal would apply to financial institutions with more than $1 billion in assets, like the Company. The rule also includes heightened standards for financial institutions with $50 billion or more in total consolidated assets that requires at least 50 percent of incentive-based payments for designated executives to be deferred for a minimum of three years. The interagency rule must be approved by all of the five federal members of the FFIEC, the SEC and the Federal Housing Finance Agency before comments on the rule are sought. Comments on the proposed interagency rule were due to the agencies by May 31, 2011. A definitive final rule is expected to be issued in 2012.

        Effective April 1, 2011, Regulation Z is amended to restrict incentive compensation programs with regard to residential mortgage programs. Such limitations affect mortgage brokers as well as loan officers in the subsidiary banks. Compensation may be tied to volume but not to terms or conditions of the transaction other than the amount of credit extended.

        The scope and content of the U.S. banking regulators' policies on executive compensation are continuing to develop and are likely to continue evolving in the near future. It cannot be determined at this time whether compliance with such policies will adversely affect the Company's ability to hire, retain and motivate its key employees.

        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. Such changes could have a material effect on the business of the Company. The Company cannot predict whether any such changes will be adopted and the Company cannot determine the ultimate effect that potential legislation, if enacted, or implementing regulations with respect thereto, would have upon the financial condition or results of operations of the Company or its subsidiaries.

Item 1A.    Risk Factors

Risk Factors

        An investment in the Company's common stock is subject to risks inherent to the Company's business. Described below are the material risks and uncertainties that management believes may affect the Company. You should carefully consider the risks and uncertainties the Company describes below and the other information in this Annual Report or incorporated by reference before deciding to invest in, or retain, shares of the Company's common stock. These are not the only risks and uncertainties that the Company faces. Additional risks and uncertainties that the Company does not know about or that the Company currently believes are immaterial, or that the Company has not predicted, may also harm the Company's business operations or adversely affect the Company. If any of these risks or uncertainties actually occurs, the Company's business, financial condition, operating results or liquidity could be materially harmed. This report is qualified in its entirety by these risk factors.

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Risks Related to the Company's Business

Losses from loan defaults may exceed the allowance the Company establishes for that purpose, which could have an adverse effect on the Company's business.

        There are inherent risks associated with the Company's lending activities. Losses from loan defaults may exceed the allowance the Company establishes for that purpose. Like all financial institutions, the Company maintains an allowance for probable loan losses to provide for losses inherent in the loan portfolio. The allowance for probable loan losses reflects management's best estimate of loan losses in the loan portfolio at the relevant balance sheet date. The level of the allowance reflects management's continuing evaluation of the specific credit risks, the Company's historical loan loss experience, current loan portfolio quality, composition and growth of the loan portfolio, and economic, political and regulatory conditions and unidentified losses inherent in the current loan portfolio. The determination of an appropriate level of loan loss allowance is an inherently difficult process and is based on numerous assumptions. In addition, bank regulatory agencies periodically review the Company's allowance for loan losses and may require an increase in the provision for probable loan losses or the recognition of further loan charge-offs, based on judgments different than those of management. As a result, the Company's allowance for loan losses may not be adequate to cover actual losses, and future provisions for loan losses may adversely affect the Company's earnings. The Company believes its allowance for probable loan losses is adequate at December 31, 2011.

If real estate values in the Company's target markets decline, the loan portfolio would be impaired.

        A significant portion of the Company's loan portfolio consists of loans secured by real estate located in the markets served by the Company. Real estate values and real estate markets are generally affected by, among other things, changes in national, regional, or local economic conditions; fluctuations in interest rates and the availability of loans to potential purchases, changes in the tax laws and other governmental statutes, regulations, and policies; and acts of nature. If real estate prices decline significantly in any of these markets, the value of the real estate collateral securing the Company's loans would be reduced. Such a reduction in the value of the Company's collateral could increase the number of impaired loans and adversely affect the Company's financial performance.

The Company's subsidiary banks face strong competition in their market areas, which may limit their asset growth and profitability.

        The Company's primary market areas are South, Central and Southeast Texas, including Austin and Houston, and the State of Oklahoma. The banking business in these areas is extremely competitive, and the level of competition facing the Company may increase further, which may limit the growth and profitability of the Company. Each of the Company's subsidiary banks experience competition in both lending and attracting funds from other banks, savings institutions, credit unions and non-bank financial institutions located within its market area, many of which are significantly larger institutions. Non-bank competitors competing for deposits and deposit type accounts include mortgage bankers and brokers, finance companies, credit unions, securities firms, money market funds, life insurance companies, and mutual funds. For loans, the Company encounters competition from other banks, savings associations, finance companies, mortgage bankers and brokers, insurance companies, small loan and credit card companies, credit unions, pension trusts, and securities firms. Many of the Company's competitors have fewer regulatory constraints and may have lower cost structures. Additionally, due to their size, many competitors may be able to achieve economies of scale and, as a result, may offer a broader range of products and services as well as better pricing for those products and services than the Company offers. Also, technology and other changes are allowing parties to complete financial transactions that historically have involved banks through alternative methods. The process of eliminating banks as intermediaries could result in the loss of fee income, as well as the loss of customer deposits and the related income generated

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from those deposits. The loss of revenue streams and the reduction of lower cost deposits as a source of funds could have a material adverse affect on the Company's financial condition and results of operations.

The Company relies, in part, on external financing to fund the Company's operations and the unavailability of such funds in the future could adversely impact the Company's growth strategy and prospects.

        The Company relies on deposits, repurchase agreements, advances from the Federal Home Loan Bank ("FHLB") of Dallas and other borrowings to fund its operations. The subsidiary banks have also historically relied on certificates of deposit. While the Company has reduced its reliance on certificates of deposit and has been successful in promoting its transaction and non-transaction deposit products (demand deposit accounts, money market, savings and checking), jumbo deposits nevertheless constituted a large portion of total deposits at December 31, 2011. Jumbo deposits tend to be a more volatile source of funding. Although management has historically been able to replace such deposits on maturity if desired, no assurance can be given that the Company would be able to replace such funds at any given point in time. If the proposed rule of the IRS that would extend the reporting requirements for interest on deposits to nonresident alien individuals who are residents of any foreign country is finalized, it may result in deposit withdrawals by nonresident alien individuals who were not previously subject to the reporting requirements, including residents of Mexico.

The Company's business is subject to interest rate risk and variations in interest rates may negatively affect the Company's financial performance.

        The Company is unable to predict fluctuations of market interest rates, which are affected by many factors, including:

•

Inflation;



•

Recession;



•

Changes in consumer spending, borrowing and saving habits;



•

A rise in unemployment;



•

Tightening of the money supply; and



•

Domestic and international disorder and instability in domestic and foreign financial markets.

        Changes in the interest rate environment may reduce the Company's profits. The Company expects that the bank subsidiaries will continue to realize income from the differential or "spread" between the interest earned on loans, securities and other interest-earning assets, and the interest paid on deposits, borrowings and other interest-bearing liabilities. Net interest spreads are affected by the difference between the maturities and repricing characteristics of interest-earning assets and interest-bearing liabilities. Earnings could be adversely affected if the net interest spreads are reduced. Changes in interest rates and other factors could result in write downs of carrying values of securities held in our securities available-for-sale portfolio and such changes could reduce earnings of the Company.

The Company is subject to extensive regulation which could adversely affect the Company including, without limitation, changes in U.S.—Mexico trade and travel along the Texas border.

        The Company's operations are subject to extensive regulation by federal, state and local governmental authorities and are subject to various laws and judicial and administrative decisions imposing requirements and restrictions on part or all of the Company's operations. Because the Company's business is highly regulated, the laws, rules and regulations applicable to the Company are subject to regular modification and change. There can be no assurance that there will be no laws, rules or regulations adopted in the future, or changes in accounting policies and practices, which could make compliance more difficult or expensive, or otherwise adversely affect the Company's business, financial condition or prospects. The

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Dodd-Frank Act, enacted in July 2010, instituted major changes to the banking and financial institutions regulatory regimes. These changes and other changes to statutes and regulations, including changes in the interpretation or implementation of statutes, regulations or policies, could affect the Company in substantial and unpredictable ways. Such changes could subject the Company to additional costs, limit the types of financial services and products the Company may offer and/or increase the ability of non-banks to offer competing financial services and products, among other things. 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. Additionally, any reductions in border crossings and commerce resulting from the Homeland Security Programs called "US-VISIT," which is derived from Section 110 of the Illegal Immigration Reform and Immigration Responsibility Act of 1996 could affect the Company negatively, and any possible negative consequences from an adverse immigration law could also have a negative effect on the Company's operations.

The Company's potential future acquisitions and branch expansion could be adversely affected by a number of factors.

        Acquisitions of other financial institutions and branch expansion have been a key element of the Company's growth. There are a number of factors that may impact the ability of the Company to continue to grow through acquisition transactions, including strong competition from other financial institutions who are active or potential acquirers of financial institutions in the existing or future markets of the Company. Acquisitions of other financial institutions and new branches must be approved by bank regulators and such approvals are dependent on many factors, including the results of regulatory examinations and CRA ratings. Unless and until IBC's CRA rating improves, the inability to receive regulatory approvals for proposed acquisitions and branch expansions could adversely affect the future growth and prospects of the Company.

The Company relies heavily on its chief executive officer.

        The Company has experienced substantial growth in assets and deposits during the past, particularly since Dennis E. Nixon became President of the Company in 1979. Although Mr. Nixon is the chief executive officer and one of the Company's substantial shareholders, the Company does not have an employment agreement with Mr. Nixon and the loss of his services could have a material adverse effect on the Company's business and prospects.

System failure or breaches of our network security could subject us to increased operating costs as well as litigation and other liabilities.

        The computer systems and network infrastructure our Company uses could be vulnerable to unforeseen problems. Our operations are dependent upon our ability to protect our computer equipment against damage from fire, power loss, telecommunications failure or a similar catastrophic event. Any damage or failure that causes an interruption in our operations could have an adverse effect on our customers. In addition, we must be able to protect the computer systems and network infrastructure utilized by us against physical damage, security breaches and service disruption caused by the Internet or other users. Such computer break-ins and other disruptions would jeopardize the security of information stored in and transmitted through our computer systems and network infrastructure, which may result in significant liability to us. While the Company conducts its own data processing, it is reliant 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 risks that these vendors will not perform in accordance with contracted arrangements and in a manner that adequately protects the operations of the Company.

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

        The Company may desire or need to raise additional capital in the future to provide it with sufficient capital resources and liquidity to meet its commitments and business needs, particularly if its asset quality or earnings were to deteriorate significantly. 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 the Company's financial performance. The Company cannot assure that such capital will be available on acceptable terms or at all. If the Company needs 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 investor. An inability to raise additional capital on acceptable terms when needed could have a materially adverse effect on the Company's businesses, financial condition and results of operations.

Severe weather, natural disasters, acts of war or terrorism and other external events could significantly impact the Company's business.

        Severe weather, natural disasters, acts of war or terrorism and other adverse external events could have a significant impact on the Company's ability to conduct business. In addition, such events could affect the stability of the Company's deposit base, impair the ability of borrowers to repay outstanding loans, impair the value of collateral securing loans, cause significant property damage, result in loss of revenue and cause the Company to incur additional expenses. Although management has established disaster recovery policies and procedures, the occurrence of any such event in the future could have a material adverse effect on the Company's business.

An impairment in the carrying value of our goodwill could negatively impact our earnings and capital.

        Goodwill is initially recorded at fair value and is not amortized, but is reviewed for impairment at least annually or more frequently if events or changes in circumstances indicate that the carrying value may not be recoverable. Given the current economic environment and conditions in the financial markets, we could be required to evaluate the recoverability of goodwill prior to our normal annual assessment if we experience disruption in our business, unexpected significant declines in our operating results, or sustained market capitalization declines. These types of events and the resulting analyses could result in goodwill impairment charges in the future, which would be recorded as charges against earnings. The decrease in earnings resulting from impairment charges could also negatively impact other performance measures; however, for regulatory purposes, goodwill is eliminated in calculating the Company's regulatory ratios such as its regulatory capital ratios. We performed an annual goodwill impairment assessment as of October 1, 2011. Based on our analyses, we concluded that the fair value of our reporting units exceeded the carrying value of our assets and liabilities and, therefore, goodwill was not considered impaired. Depending on the response of the financial industry to the legal, regulatory and competitive changes related to interchange fees, overdraft services and interest on demand deposit accounts, financial institutions may need to change their policies, procedures and operating plans in the future to compete more effectively and such changes may require certain financial institutions to take a goodwill impairment charge to account for anticipated reduction in revenue related to such changes.

The Company Is Subject To Environmental Liability Risk Associate 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

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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. 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.

The Company's Controls and Procedures May Fail or be Circumvented

        Management regularly reviews and updates the Company's internal controls, disclosure controls and procedures and corporate governance policies and procedures. Any system of controls, however well designed and operated, is based in part on certain assumptions and can provide only reasonable, not absolute, assurances that the objectives of the system are met. Any failure or circumvention of the Company's controls and procedures or failure to comply with regulations related to controls and procedures could have a material adverse effect on the Company's business, results of operations and financial condition.

New Lines of Business or New Products and Services May be Subject the Company to Additional Risks

        From time to time, the Company may implement 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 may not be achieved and price and profitability targets may not prove feasible. 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. 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, results of operations and financial condition.

The downgrade of the U.S. credit rating and Europe's ongoing debt crisis could negatively impact our business, financial condition and liquidity.

        Standard and Poor's lowered the U.S. long term sovereign credit rating from AAA to AA+ on August 5, 2011. The downgrade and a further downgrade or a downgrade by other ratings agencies of the U.S. government's sovereign credit rating, or its perceived creditworthiness, could adversely affect the financial markets and economic conditions in the United States and worldwide. Many of our investment securities are issued by U.S. government agencies and U.S. government sponsored entities ("GSEs"). The rating downgrade could affect the stability of residential mortgage-backed securities issued or guaranteed by GSEs. These factors could affect the liquidity or valuation of our current portfolio of residential mortgage-backed securities issued or guaranteed by GSEs, and could result in our counterparties requiring additional collateral for our borrowings and could increase our borrowing costs. Because of the unprecedented nature of any negative credit rating actions with respect to U.S. government obligations, the ultimate impact on global markets and our business, financial condition and liquidity are unpredictable and may not be immediately apparent; however, any adverse impact related to the downgrade of the U.S. sovereign credit rating could have a material adverse effect on the Company's liquidity, financial condition and results of operations. Additionally, concerns about the European Union's sovereign debt crisis have also caused uncertainty for financial markets globally. Such risks could indirectly affect the Company by affecting the Company's customers with European businesses or assets denominated in the euro or companies in the Company's market with European businesses or affiliates.

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Risks Related to the Company's Industry

Changes in economic and political conditions could adversely affect the Company's earnings, as our borrowers' ability to repay loans and the value of the collateral securing our loans decline.

        The Company's success depends, to a certain extent, upon economic and political conditions, local, national and international with respect to Mexico, as well as governmental monetary policies. Conditions such as inflation, recession, unemployment, changes in interest rates, changes in capital markets, money supply, political issues, legislative and regulatory changes and other factors beyond the Company's control may adversely affect the Company's asset quality, deposit levels and loan demand and, therefore, the Company's earnings. The Company is particularly affected by conditions in its primary market areas of South, Central and Southeast Texas, including Austin and Houston, and the State of Oklahoma. While economic conditions in the Company's primary markets have begun to improve, there is no assurance that the improvement will continue. If the weakened economic conditions in the Company's primary market areas worsen or fail to improve, the Company could experience an increase in loan delinquencies and non-performing assets, decreases in loan collateral values and a decrease in demand for the Company's products and services, any of which could have a material adverse impact on the Company's financial condition and results of operations.

The Company depends on the accuracy and completeness of information about customers and counterparties as well as the soundness of other financial institutions with which the Company interacts.

        In deciding whether to extend credit or enter into other transactions, the Company may rely on information furnished by or on behalf of customers and counterparties, including financial statements, credit reports and other financial information. The Company may also rely on representations of those customers, counterparties, financial institutions or other third parties, such as independent auditors, as to the accuracy and completeness of that information. Reliance on inaccurate or misleading financial statements, credit reports or other financial information or problems with the soundness of other financial institutions with which the Company interacts could have a material adverse impact on the Company's business and, in turn, the Company's financial condition and results of operations.

If the Company does not adjust to rapid changes in the financial services industry, its financial performance may suffer.

        The Company's ability to deliver strong financial performance and returns on investment to shareholders will depend in part on its ability to expand the scope of available financial services to meet the needs and demands of its customers and its ability to stay abreast of technological innovations and evaluate those technologies that will enable it to compete on a cost-effective basis.

        In addition to the challenge of competing against other banks in attracting and retaining customers for traditional banking services, the Company's competitors also include securities dealers, brokers, mortgage bankers, investment advisors, specialty finance and insurance companies who seek to offer one-stop financial services that may include services that banks have not been able or allowed to offer to their customers in the past. The increasingly competitive environment is primarily a result of changes in regulation, changes in technology and product delivery systems and the accelerating pace of consolidation among financial service providers. Such changes in the financial industry may result in the loss of fee income, as well as the loss of customer deposits and the related income generated from those deposits. The loss of these revenue streams and the lower cost deposits as a source of funds could have a material adverse effect on the Company's financial condition and results of operations.

        Further, the costs of new technology, including personnel, can be high in both absolute and relative terms. There can be no assurance, given the fast pace of change and innovation, that the Company's technology, either purchased or developed internally, will meet or continue to meet the needs of the Company and the needs of our customers.

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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. As a result, beginning on July 21, 2011, financial institutions were allowed to commence offering 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 a material adverse effect on the Company's business, financial condition and results of operations.

The Dodd-Frank Regulatory Reform Act and other regulatory developments could negatively impact the revenue streams of the Company related to interchange fees and consumer services and result in a contraction of retail banking of the Company.

        The Dodd-Frank Reform Act authorizes the Federal Reserve to regulate interchange fees paid to banks on debit card transactions to ensure that they are reasonable and proportional to the cost of processing individual transactions, and prohibits debit card networks and issuers from requiring transactions to be processed on a single payment network. The impact of the FDIC Overdraft Payment Supervisory Guidance could jeopardize the profitability of a number of retail sites of the Company and could result in a reduction of revenue from the Company's overdraft courtesy services. The Reform Act created the CFPB. While banks with less than $10 billion in assets, such as each of the subsidiary banks of the Company, based on their asset size as of June 30, 2011, are exempt from the primary examination and enforcement powers of the CFPB, the new agency's rulemaking will affect all banks. The impact of the CFPB is uncertain at this time, but the initiatives of the CFPB could negatively impact revenue streams of the Company related to consumer services. The reduction of revenue from retail banking services coupled with the repeal of the federal prohibition on the payment of interest on demand deposits, could result in a contraction of retail banking of the Company. The Company closed fifty-five in-store branches during the fourth quarter of 2011 due to reduced levels of revenue resulting from regulatory changes limiting interchange fees in order to align the Company's expenses with the reduced levels of revenue.

The limitation of preemption in the Dodd-Frank Reform Act, the powers of the new Consumer Financial Protection Bureau, and the FDIC Overdraft Payment Supervisory Guidance may increase the likelihood of lawsuits against financial institutions.

        The Dodd-Frank Reform Act provides that courts must make preemption determinations on a case-by-case basis with the respect to particular state laws and can no longer rely on blanket preemption determinations. The new CFPB is specifically authorized to protect consumers from "unfair," "deceptive," and "abusive" acts and practices. Depending on the future actions of the CFPB, the likelihood of lawsuits against financial institutions related to allegedly "unfair," "deceptive" and "abusive" acts and practices could increase. Depending on the future actions of the FDIC Overdraft Payment Supervisory Guidance could result in an increase of lawsuits related to the overdraft courtesy services of financial institutions. There are already a number of lawsuits pending against financial institutions in multi-district proceedings known as "In re Checking Account Overdraft Litigation" related to the overdraft courtesy program of financial institutions. In the third quarter of 2010, IBC was named as a defendant in two purported class-action lawsuits, including one filed in the United States District Court for the Southern District of Texas and one filed in the United States District Court for the Southern District of Florida in the multi-district proceeding. In January 2011, the Texas lawsuit was dismissed without prejudice when the parties stipulated to arbitrate the matter. The Florida lawsuit was dismissed without prejudice on September 30, 2011, when the parties settled the matter. The amount expensed by the Company in connection with the settlement of the lawsuit was not significant.

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Risks Related to the Company's Stock

The Company's stock price may be volatile.

        Several factors could cause the Company's stock price to fluctuate substantially in the future. These factors include among other things:

•

Actual or anticipated variations in earnings;



•

Recommendations by securities analysts;



•

The Company's announcements of developments related to its businesses;



•

Operating and stock performance of other companies deemed to be peers;



•

New technology used or services offered by traditional and non-traditional competitors;



•

Continued low trading volume in the Company's stock;



•

The volatile impact of short selling activity in the Company's stock;



•

News reports of trends, concerns and other issues related to the financial services industry; and



•

Changes in the Company's ability to pay dividends;



•

Changes in government regulations, policies and guidance.

        The Company's stock price may fluctuate significantly in the future, and these fluctuations may be unrelated to the Company's performance. General market price declines or market volatility in the future could adversely affect the price of its common stock, and the current market price may not be indicative of future market prices.

The holders of our junior subordinated debentures have rights that are senior to those of our shareholders.

        As of December 31, 2011, we had approximately $191 million in junior subordinated debentures outstanding that were issued to our statutory trusts. The trusts purchased the junior subordinated debentures from us 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 us to the extent not paid or made by each trust, provided the trust has funds available for such obligations.

        The junior subordinated debentures are senior to our shares of common stock and the Senior Preferred Stock. As a result, we must make payments on the junior subordinated debentures (and the related trust preferred securities) before any dividends can be paid on our common stock or preferred stock and, in the event of our bankruptcy, dissolution or liquidation, the holders of the debentures must be satisfied before any distributions can be made to our shareholders. If certain conditions are met, we have the right to defer interest payments on the junior subordinated debentures (and the related trust preferred securities) at any time or from time to time for a period not to exceed up to 20 consecutive quarters in a deferral period during which time no dividends may be paid to holders of our common stock or preferred stock.

Risks Related to Participation in the CPP

We may be adversely affected by our participation in the CPP.

        In connection with our sale of Senior Preferred Stock to the Treasury Department under the Capital Purchase Program, the Company also issued to the Treasury Department a warrant to purchase 1,326,238 shares of our common stock. The terms of the transaction with the Treasury resulted in limitations on our ability to pay dividends and repurchase our shares, which restrictions expired on December 23, 2011. Until December 23, 2011, the Company was not allowed to increase cash dividends above pre-TARP levels ($.33

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per share of common stock on a semi-annual basis). In addition, the Company is not allowed to pay any dividends on its common stock unless it is current on its dividend payments on the Senior Preferred Stock. These restrictions, as well as the dilutive impact of the warrant, may have a negative effect on the market price of our common stock.

        Unless the Company is able to redeem the Senior Preferred Stock prior to February 15, 2014, the cost of this capital will increase substantially on that date, from 5.00% on the liquidation preference of $1,000 per share of Senior Preferred Stock (approximately $10,800,000 annually) to 9.00% on the liquidation preference of $1,000 per share of Senior Preferred Stock (approximately $19,440,000 annually). Depending on our financial condition at the time, this increase in dividends on the Series A Preferred Stock could have a negative effect on our liquidity.

        The terms of the Securities Purchase Agreement in which we entered into with Treasury pursuant to the CPP provides that the Treasury may unilaterally amend any provision of the Securities Purchase Agreement to the extent required to comply with any changes in applicable federal law that may occur in the future. We have no assurances that changes in applicable law affecting the Securities Purchase Agreement will not occur in the future. Such changes may place restrictions on our business or results of operations, which may adversely affect the market price of our common stock.

        The programs established or to be established under the EESA and Capital Purchase Program may have adverse effects upon the Company. The Company may face increased regulation of the financial services industry. Compliance with such regulation may increase the Company's costs and limit its ability to pursue business opportunities. The affects of additional CPP related legislation and regulatory programs on the Company cannot reliably be determined at this time.

You may not receive dividends on the common stock.

        Holders of our common stock are entitled to receive dividends only when, as and if declared by our Board of Directors. Although we have historically declared cash dividends on our common stock, we are not required to do so and our Board of Directors may reduce or eliminate our common stock dividend in the future. Further, the terms of the Senior Preferred Stock limit our payment of dividends on common stock, as described above. This could adversely affect the market price of our common stock.

We may experience increases in the cost of compensation programs

        In addition, pursuant to the Securities Purchase Agreement we adopted Treasury's standards for executive compensation for the period during which the Treasury holds the equity issued pursuant to the Securities Purchase Agreement, including the common stock that may be issued pursuant to the warrant. These standards include an agreement not to deduct for tax purposes executive compensation in excess of $500,000 for each applicable senior executive. This change to the deductibility limit on executive compensation increased the costs of our compensation programs for the year ended December 31, 2011 and will likely increase the overall cost of our compensation programs in future periods during with the Company is a TARP participant.

We may lose members of our management team due to compensation restrictions.

        The Company's ability to retain key officers and employees may be negatively impacted by recent legislation and regulation affecting the financial services industry. On February 17, 2009, the American Recovery and Reinvestment Act of 2009 (the "ARRA") was signed into law and the related rules of the Treasury Department were adopted on June 15, 2009. The ARRA, among other things, significantly expands the executive compensation restrictions previously imposed by the Emergency Economic Stabilization Act of 2008. Such restrictions apply to any entity that has received or will receive funds under the TARP Capital Purchase Program, and shall generally continue to apply for as long as any of the preferred stock issued under the Capital Purchase Program remains outstanding and held by the Treasury

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Department. As a result of our participation in the TARP Capital Purchase Program, the restrictions and standards set forth in the ARRA shall be applicable to the Company, subject to regulations promulgated by the U.S. Treasury. Such restrictions and standards may further impact management's ability to retain key officers and employees as well as the Company's ability to compete with financial institutions that are not subject to the same limitations as the Company under the ARRA.

Item 1B.    Unresolved Staff Comments

        N/A

Item 2.    Properties

        The principal offices of the Company and IBC are located at 1200 San Bernardo Avenue, Laredo, Texas and 2418 Jacaman Road, Laredo, Texas in buildings owned and completely occupied by the Company and IBC and containing approximately 147,000 square feet. The bank subsidiaries of IBC have 217 main banking and branch facilities. All the facilities are customary to the banking industry. The bank subsidiaries own most of their banking facilities and the remainder are leased. The facilities are located in the regions of Laredo, San Antonio, Houston, Zapata, Eagle Pass, the Rio Grande Valley of Texas, the Coastal Bend area of Texas, and throughout the State of Oklahoma.

        As Texas state-chartered banks, no bank subsidiary of the Company may, without the prior written consent of the Banking Commissioner, invest an amount in excess of its Tier 1 capital in bank facilities, furniture, fixtures and equipment. None of the Company's bank subsidiaries exceeds such limitation.

Item 3.    Legal Proceedings

        The Company and its bank subsidiaries are involved in various legal proceedings that are in various stages of litigation. Some of these actions allege "lender liability" claims on a variety of theories and claim substantial actual and punitive damages. The Company and its subsidiaries have determined, based on discussions with their counsel that any material loss in such actions, individually or in the aggregate, is remote or the damages sought, even if fully recovered, would not be considered material to the consolidated financial position or results of operations of the Company and its subsidiaries. However, many of these matters are in various stages of proceedings and further developments could cause management to revise its assessment of these matters. Further information regarding legal proceedings has been provided in Note 17 of the Notes to consolidated financial statements located on page 73 of the 2011 Annual Report to Shareholders which is incorporated herein by reference.

Item 4.    Mine Safety Disclosures

        None.

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Item 4A.    Executive Officers of the Registrant

        Certain information is set forth in the following table concerning the executive officers of the Company, each of whom has been elected to serve until the 2012 Annual Meeting of Shareholders and until his successor is duly elected and qualified.

        There are no family relationships among any of the named persons. Each executive officer has held the same position or another executive position with the Company during the past five years.

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PART II

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

        The information set forth under the caption "Preferred Stock, Common Stock and Dividends," "Stock Repurchase Program," and "Equity Compensation Plan Information" located on pages 27 through 30 of Registrant's 2011 Annual Report is incorporated herein by reference.

Item 6.    Selected Financial Data

        The information set forth under the caption "Selected Financial Data" located on page 1 of Registrant's 2011 Annual Report is incorporated herein by reference.

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

        The information set forth under the caption "Management's Discussion and Analysis of Financial Condition and Results of Operations" located on pages 2 through 30 of Registrant's 2011 Annual Report is incorporated herein by reference.

Item 7A.    Quantitative and Qualitative Disclosures about Market Risk

        The information set forth under the caption "Liquidity and Capital Resources" located on pages 21 through 26 of Registrant's 2010 Annual Report is incorporated herein by reference.

Item 8.    Financial Statements and Supplementary Data

        The consolidated financial statements located on pages 31 through 90 of Registrant's 2011 Annual Report are incorporated herein by reference.

        The condensed quarterly income statements located on pages 91 and 92 of Registrant's 2011 Annual Report are incorporated herein by reference.

Item 9.    Changes In and Disagreements with Accountants on Accounting and Financial Disclosure

        None.

Item 9A.    Controls and Procedures

        As of the end of the period covered by this Annual Report on Form 10-K, an evaluation was carried out by the management of International Bancshares Corporation, (the "Company") with the participation of its Chief Executive Officer and Chief Financial Officer, of the effectiveness of the Company's disclosure controls and procedures (as defined in Rule 13a-15(e) under the Securities Exchange Act of 1934). Based upon that evaluation, the Chief Executive Officer and Chief Financial Officer concluded that the disclosure controls and procedures were effective as of the end of the period covered by this report. Additionally, there were no changes in the Company's internal control over financial reporting that occurred during the quarter ended December 31, 2011 that have materially affected, or are reasonably likely to materially affect, the Company's internal control over financial reporting.

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Management's Report on Internal Control Over Financial Reporting

        The management of the Company is responsible for establishing and maintaining adequate internal controls over financial reporting, as defined under Rules 13a-15(f) and 15d-15(f) of the Securities Exchange Act of 1934. The Company's internal control over financial reporting is a process designed under the supervision of the Company's Chief Executive Officer and Chief Financial Officer to provide reasonable assurance regarding the reliability of financial reporting and the preparation of the Company's financial statements for external purposes in accordance with generally accepted accounting principles.

        As of December 31, 2011, management assessed the effectiveness of the design and operation of the Company's internal controls over financial reporting based on the criteria for effective internal control over financial reporting established in "Internal Control—Integrated Framework," issued by the Committee of Sponsoring Organizations (COSO) of the Treadway Commission. Based on the assessment, management determined that the Company maintained effective internal control over financial reporting as of December 31, 2011, based on those criteria.

        McGladrey & Pullen, LLP, the independent registered public accounting firm that audited the 2011 consolidated financial statements of the Company included in this Annual Report on Form 10-K, has audited the effectiveness of the Company's internal control over financial reporting as of December 31, 2011. Their report, which expresses an unqualified opinion, on the effectiveness of the Company's internal control over financial reporting as of December 31, 2011 is included in this Item under the heading "Report of Independent Registered Public Accounting Firm."

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Report of Independent Registered Public Accounting Firm

The Board of Directors and Shareholders
International Bancshares Corporation:

        We have audited International Bancshares Corporation and subsidiaries' (the "Company") internal control over financial reporting as of December 31, 2011, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission. International Bancshares Corporation and subsidiaries' management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management's Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company's internal control over financial reporting based on our audit.

        We conducted our audit in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control, based on the assessed risk. Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

        A company's internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company's internal control over financial reporting includes those policies and procedures that (a) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (b) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorization of management and directors of the company; and (c) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company's assets that could have a material effect on the financial statements.

        Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

        In our opinion, International Bancshares Corporation and subsidiaries maintained, in all material respects, effective internal control over financial reporting as of December 31, 2011, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission.

        We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), the consolidated statements of condition as of December 31, 2011 and 2010, and the related consolidated statements of income, comprehensive income, shareholders' equity, and cash flows of International Bancshares Corporation and subsidiaries and our report dated February 27, 2012 expressed an unqualified opinion.

/s/ McGladrey & Pullen, LLP

Dallas, TX
February 27, 2012

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Item 9B.    Other Information

        None.

PART III

Item 10.    Directors, Executive Officers and Corporate Governance

        There is incorporated in this Item 10 by reference (i) that portion of the Company's definitive proxy statement relating to the Company's 2012 Annual Meeting of Shareholders entitled "ELECTION OF DIRECTORS," (ii) the portion of the Company's definitive proxy statement entitled "Audit Committee" in the portion entitled "MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS," (iii) the portion of the Company's definitive proxy statement entitled "Code of Ethics," in the portion entitled "CORPORATE GOVERNANCE," (iv) that portion of the Company's definitive proxy statement entitled "SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE," and (v) Item 4A of this report entitled "Executive Officers of the Registrant."

Item 11.    Executive Compensation

        There is incorporated in this Item 11 by reference (i) that portion of the Company's definitive proxy statement relating to the Company's 2012 Annual Meeting of Shareholders entitled "EXECUTIVE COMPENSATION," which includes, without limitation, the compensation committee certification required under the CPP and the portion entitled "Executive Compensation Tables", and (ii) that portion entitled "Compensation Committee and Stock Option Plan Committee Interlocks and Insider Participation" in the portion entitled "MEETINGS AND COMMITTEES OF THE BOARD OF DIRECTORS."

Item 12.    Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

        There are incorporated in this Item 12 by reference those portions of the Company's definitive proxy statement relating to the Company's 2012 Annual Meeting of Shareholders entitled "PRINCIPAL SHAREHOLDERS," "SECURITY OWNERSHIP OF MANAGEMENT," and "Equity Compensation Plan Information" in the portion entitled "EXECUTIVE COMPENSATION."

Item 13.    Certain Relationships and Related Transactions, and Director Independence

        There is incorporated in this Item 13 by reference (i) that portion of the Company's definitive proxy statement relating to the Company's 2012 Annual Meeting of Shareholders entitled "INTEREST OF MANAGEMENT IN CERTAIN TRANSACTIONS" and (ii) that portion entitled "Director Independence" in the portion entitled "CORPORATE GOVERNANCE."

Item 14.    Principal Accounting Fees and Services

        There is incorporated in this Item 14 by reference that portion of the Company's definitive proxy statement relating to the Company's 2012 Annual Meeting of Shareholders entitled "PRINCIPAL ACCOUNTANT FEES AND SERVICES."

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PART IV

Item 15.    Exhibits, Financial Statement Schedules

(a)

Documents

1.

The consolidated financial statements of the Company and subsidiaries are incorporated into Item 8 of this report by reference from the 2011 Annual Report to Shareholders filed as an exhibit hereto and they include:

Reports of Independent Registered Public Accounting Firm

Consolidated:
Statements of Condition as of December 31, 2011 and 2010
Statements of Income for the years ended December 31, 2011, 2010 and 2009
Statements of Comprehensive Income for the years ended December 31, 2011, 2010 and 2009
Statements of Shareholders' Equity for the years ended December 31, 2011, 2010 and 2009
Statements of Cash Flows for the years ended December 31, 2011, 2010 and 2009
Notes to Consolidated Financial Statements

2.

All Financial Statement Schedules are omitted as the required information is inapplicable or the information is presented in the consolidated financial statements or related notes.



3.

The following exhibits have previously been filed by the Registrant or are included in this report following the Index to Exhibits:

40

41

42

SIGNATURES

        Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

        Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed by the following persons on behalf of the Registrant and in the capacities and on the date indicated.

43

44

Exhibit Index

45

QuickLinks

Item 1. Business

Item 1A. Risk Factors

Item 1B. Unresolved Staff Comments
Item 2. Properties
Item 3. Legal Proceedings
Item 4. Mine Safety Disclosures
Item 4A. Executive Officers of the Registrant

Item 5. Market for the Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities
Item 6. Selected Financial Data
Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations
Item 7A. Quantitative and Qualitative Disclosures about Market Risk
Item 8. Financial Statements and Supplementary Data
Item 9. Changes In and Disagreements with Accountants on Accounting and Financial Disclosure
Item 9A. Controls and Procedures

Item 9B. Other Information

Item 10. Directors, Executive Officers and Corporate Governance
Item 11. Executive Compensation
Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters
Item 13. Certain Relationships and Related Transactions, and Director Independence
Item 14. Principal Accounting Fees and Services

Item 15. Exhibits, Financial Statement Schedules