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

FORM 10-K

Commission file number 00-30747

PACWEST BANCORP
(Exact Name of Registrant as Specified in Its Charter)

Registrant's telephone number, including area code: (310) 286-1144

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

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

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

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

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

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

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

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

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

         As of June 30, 2010, the aggregate market value of the voting common stock held by non-affiliates of the registrant, computed by reference to the average high and low sales prices on The Nasdaq Global Select Market as of the close of business on June 30, 2010, was approximately $562.8 million. Registrant does not have any nonvoting common equities.

         As of March 2, 2011, there were 35,461,610 shares of registrant's common stock outstanding, excluding 1,426,687 shares of unvested restricted stock.

DOCUMENTS INCORPORATED BY REFERENCE

         The information required by Items 10, 11, 12, 13 and 14 of Part III of this Annual Report on Form 10-K will be found in the Company's definitive proxy statement for its 2011 Annual Meeting of Stockholders, to be filed pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended, and such information is incorporated herein by this reference.

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PACWEST BANCORP

2010 ANNUAL REPORT ON FORM 10-K

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PACWEST BANCORP

2010 ANNUAL REPORT ON FORM 10-K

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PART I

ITEM 1.    BUSINESS

General

        PacWest Bancorp is a bank holding company registered under the Bank Holding Company Act of 1956, as amended. Our principal business is to serve as the holding company for our banking subsidiary, Pacific Western Bank, which we refer to as Pacific Western or the Bank. When we say "we", "our" or the "Company", we mean the Company on a consolidated basis with the Bank. When we refer to "PacWest" or to the holding company, we are referring to the parent company on a stand-alone basis.

        PacWest Bancorp was formerly known as First Community Bancorp. At a special meeting of the Company's shareholders held on April 23, 2008, the shareholders approved the reincorporation of the Company in Delaware from California and the change of the Company's name to PacWest Bancorp from First Community Bancorp. The reincorporation became effective on May 14, 2008. In connection with the reincorporation and name change, the Company also changed its ticker symbol on the NASDAQ Global Select Market to "PACW." Other than the name change, change in ticker symbol and change in corporate domicile, the reincorporation did not result in any change in the business, physical location, management, assets, liabilities or total stockholders' equity of the Company, nor did it result in any change in location of the Company's employees, including the Company's management. Additionally, the reincorporation did not alter any shareholder's percentage ownership interest or number of shares owned in the Company. The stockholders' equity section of the accompanying consolidated financial statements has been restated retroactively to give effect to the reincorporation. Such reclassification had no effect on the results of operations or the total amount of stockholders' equity.

Recent Transactions

        During 2010, we completed the following transactions:

•

In December, we sold $74.9 million in non-covered adversely classified loans, of which $17.6 million were nonaccrual loans and $43.7 million were performing restructured loans.



•

In August, we acquired Los Padres Bank in an FDIC-assisted transaction, which included $437.1 million in loans and $752.2 million in deposits. We recorded $47.3 million in goodwill in connection with this acquisition.



•

In July, we purchased $234.1 million of performing loans secured by Southern California real estate.



•

In March, holders of the Series A warrants issued in August 2009 exercised them. We issued 1,348,040 shares of common stock for net proceeds of approximately $26.6 million after expenses. Subsequently, in August, the Series B warrants issued in August 2009 expired unexercised.



•

In February, we sold $323.6 million in non-covered adversely classified loans, of which $110.5 million were nonaccrual loans and $105.1 million were performing restructured loans.

        During 2009, we completed the following transactions:

•

In December, we filed a registration statement with the Securities and Exchange Commission ("SEC") to offer to sell, from time to time, shares of common stock, preferred stock, depositary shares, and warrants for an aggregate initial offering price up to $350 million. The registration statement was declared effective January 8, 2010.

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•

In August, we acquired Affinity Bank in an FDIC-assisted transaction, which included $675.6 million in loans and $868.2 million in deposits. We recorded a gain of $67.0 million in connection with this transaction.



•

In August, we sold in a direct placement to institutional investors 2.7 million shares of common stock for $50 million, and issued to each investor two warrants, Series A and Series B, exercisable for common shares at $20.20 per share, with expiration dates in March 2010 and August 2010, respectively.



•

In June, we filed a registration statement with the SEC to offer to sell, from time to time, shares of stock for an aggregate initial offering price up to $150 million. The registration statement was declared effective June 30, 2009, but terminated when the $350 million shelf registration became effective on January 8, 2010.



•

In January, we issued 3,846,153 common shares at $26.00 per share for total cash consideration of approximately $100 million in a private placement to CapGen Capital Group II LP.

        See "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations—Overview" and Notes 3, 4, 6 and 18 of the Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data" for further information regarding recent transactions.

Banking Business

        Pacific Western is a full-service commercial bank offering a broad range of banking products and services including: accepting time and demand deposits; originating loans, including commercial, real estate construction, real estate miniperm, SBA guaranteed and consumer loans; and providing other business-oriented products. We have 77 full-service community banking branches. Our operations are primarily located in Southern California and the Bank focuses on conducting business with small to medium size businesses and the owners and employees of those businesses. The majority of our loans are secured by the real estate collateral of such businesses. We extend credit to customers located primarily in counties we serve. We also provide asset-based lending and factoring of accounts receivable to small businesses located throughout Arizona, California, and the Pacific Northwest through BFI Business Finance, or BFI, based in San Jose, California and First Community Financial, or FCF, based in Phoenix, Arizona. Special services, including international banking services, multi-state deposit services and investment services, or requests beyond the lending limits of the Bank can be arranged through correspondent banks. The Bank also issues ATM and debit cards, has a network of branded ATMs and offers access to ATM networks through other major service providers. We provide access to customer accounts via a 24-hour seven day a week toll-free automated telephone customer service and a secure online banking service.

        At December 31, 2010 our assets totaled $5.5 billion, of which gross non-covered loans totaled $3.2 billion, or 57% of assets, and covered loans totaled $908.6 million, or 16% of assets. At this date, the non-covered loans were composed of approximately 22% in commercial loans, 64% in commercial real estate loans, 8% in residential real estate loans, 3% in commercial real estate construction loans, 2% in residential real estate construction loans, and 1% in consumer and other loans. These percentages include some foreign loans, primarily to entities, and on a limited basis to individuals, with business in Mexico, representing 1% of non-covered loans.

        We are committed to maintaining premier, relationship-based community banking in Southern California serving the needs of those businesses in our marketplace, as well as serving the needs of growing businesses that may not yet meet the credit standards of the Bank through tightly controlled asset-based lending and factoring of accounts receivable. We compete actively for deposits, and emphasize solicitation of noninterest-bearing deposits. In managing the top line of our business, we focus on making quality loans and gathering low-cost deposits to maximize our net interest margin, as

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net interest income accounted for 84% of our net revenues (net interest income plus noninterest income) in 2010. The strategy for serving our target markets is the delivery of a finely-focused set of value-added products and services that satisfy the primary needs of our customers, emphasizing superior service and relationships over transaction volume or low pricing.

        We generate our revenue primarily from the interest received on the various loan products and investment securities and fees from providing deposit services, foreign exchange services and extending credit. Our major operating expenses are the interest paid by the Bank on deposits and borrowings, employee compensation and general operating expenses. The Bank relies on a foundation of locally generated deposits to fund loans. Our Bank has a relatively low cost of funds due to a high percentage of noninterest-bearing and low cost deposits to total deposits. Our operations, similar to other financial institutions with operations predominately focused in Southern California, are significantly influenced by economic conditions in Southern California, including the strength of the real estate market, the fiscal and regulatory policies of the federal and state government and the regulatory authorities that govern financial institutions. See "—Supervision and Regulation." Through our offices located in Northern California and our asset-based lending operations with production and marketing offices located in Arizona, Northern California, and the Pacific Northwest, we are also subject to the economic conditions affecting these markets.

Lending Activities

        Through the Bank, the Company concentrates its lending activities in four principal areas:

        (1)    Real Estate Loans.    Real estate loans are comprised of construction loans, miniperm loans collateralized by first or junior deeds of trust on specific commercial properties and equity lines of credit. The properties collateralizing real estate loans are principally located in our primary market areas of Los Angeles, Orange, San Bernardino, Riverside, San Diego, Ventura, Santa Barbara and San Luis Obispo counties in California and the neighboring communities. Construction loans are comprised of loans on commercial, residential and income producing properties that generally have terms of less than two years and typically bear an interest rate that floats with the Bank's base rate or another established index. Miniperm loans finance the purchase and/or ownership of commercial properties, including owner-occupied and income producing properties. Miniperm loans are generally made with an amortization schedule ranging from 15 to 25 years with a lump sum balloon payment due in one to ten years. Equity lines of credit are revolving lines of credit collateralized by junior deeds of trust on residential real properties. They generally bear a rate of interest that floats with the Bank's base rate or the prime rate and have maturities of ten years. From time to time, we purchase participation interests in loans originated by other financial institutions. These loans are subject generally to the same underwriting criteria and approval process as loans originated directly by us.

        The Bank's real estate portfolio is subject to certain risks, including, but not limited to: (i) the effects of economic downturns in the Southern California economy and in general; (ii) interest rate increases; (iii) reduction in real estate values in Southern California and in general; (iv) increased competition in pricing and loan structure; (v) the borrower's ability to refinance or payoff the balloon or line of credit at maturity; and (vi) environmental risks, including natural disasters. In addition to the foregoing, construction loans are also subject to project specific risks including, but not limited to: (a) construction costs being more than anticipated; (b) construction taking longer than anticipated; (c) failure by developers and contractors to meet project specifications; (d) disagreement between contractors, subcontractors and developers; (e) demand for completed projects being less than anticipated; (f) buyers being unable to secure financing; and (g) loss through foreclosure.

        When underwriting loans, we strive to reduce the exposure to such risks by (i) reviewing each loan request and renewal individually, (ii) using a dual signature approval system for the approval of each loan request for loans over a certain dollar amount, (iii) adhering to written loan policies, including,

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among other factors, minimum collateral requirements, maximum loan-to-value ratio requirements, cash flow requirements and personal guarantees, (iv) obtaining independent third party appraisals which are reviewed by the Bank's appraisal department, (v) obtaining external independent credit reviews, (vi) evaluating concentrations as a percentage of capital and loans, and (vii) conducting environmental reviews, where appropriate. With respect to construction loans, in addition to the foregoing, we attempt to mitigate project specific risks by: (a) implementing a controlled disbursement process for loan proceeds in accordance with an agreed upon schedule; (b) conducting project site visits; and (c) adhering to release-price schedules to ensure the prices for which newly-built units to be sold are sufficient to repay the Bank. The risks related to buyer inability to secure financing and loss through foreclosure are not controllable. We review each loan request on the basis of our ability to recover both principal and interest in view of the inherent risks.

        (2)    Commercial Loans.    Commercial loans, both domestic and foreign, are made to finance operations, to provide working capital, or for specific purposes such as to finance the purchase of assets, equipment or inventory. Since a borrower's cash flow from operations is generally the primary source of repayment, our policies provide specific guidelines regarding required debt coverage and other important financial ratios. Commercial loans include lines of credit and commercial term loans. Lines of credit are extended to businesses or individuals based on the financial strength and integrity of the borrower and guarantor(s) and generally (with some exceptions) are collateralized by short-term assets such as accounts receivable, inventory, equipment or real estate and have a maturity of one year or less. Such lines of credit bear an interest rate that floats with the Bank's base rate, LIBOR or another established index. Commercial term loans are typically made to finance the acquisition of fixed assets, refinance short-term debt originally used to purchase fixed assets or, in rare cases, to finance the purchase of businesses. Commercial term loans generally have terms from one to five years. They may be collateralized by the asset being acquired or other available assets and bear interest rates which either float with the Bank's base rate, LIBOR or another established index or remain fixed for the term of the loan.

        The Bank's portfolio of commercial loans is subject to certain risks, including, but not limited to: (i) the effects of economic downturns in the Southern California economy; (ii) interest rate increases; (iii) deterioration of the value of the underlying collateral; and (iv) the deterioration of a borrower's or guarantor's financial capabilities. We strive to reduce the exposure to such risks through: (a) reviewing each loan request and renewal individually; (b) using a dual signature approval system; (c) adhering to written loan policies; (d) obtaining external independent credit reviews, and (e) in the case of certain commercial loans to Mexican or foreign entities, third party insurance which limits our exposure to anywhere from 20 to 30 percent of the underlying loan. In addition, loans based on short-term asset values and factoring arrangements are monitored on a daily, weekly, monthly or quarterly basis and may include lockbox or control account arrangements. In general, the Bank receives and reviews financial statements and other documents of borrowing customers on an ongoing basis during the term of the relationship and responds to any deterioration noted.

        (3)    SBA Loans.    SBA loans are made through programs designed by the federal government to assist the small business community in obtaining financing from financial institutions that are given government guarantees as an incentive to make the loans. Our SBA loans fall into two categories, loans originated under the SBA's 7a Program ("7a Loans") and loans originated under the SBA's 504 Program ("504 Loans"). SBA 7a Loans are commercial business loans generally made for the purpose of purchasing real estate to be occupied by the business owner, providing working capital, and/or purchasing equipment, accounts receivable or inventory. SBA 504 Loans are collateralized by commercial real estate and are generally made to business owners for the purpose of purchasing or improving real estate for their use and for equipment used in their business. Due to declining SBA loan origination and loan sale opportunities, we suspended our loan sale operation during 2008 and reduced staff accordingly.

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        SBA lending is subject to federal legislation that can affect the availability and funding of the program. From time to time, this dependence on legislative funding causes limitations and uncertainties with regard to the continued funding of such programs, which could potentially have an adverse financial impact on our business.

        The Bank's portfolio of SBA loans is subject to certain risks, including, but not limited to: (i) the effects of economic downturns in the Southern California economy; (ii) interest rate increases; (iii) deterioration of the value of the underlying collateral; and (iv) the deterioration of a borrower's or guarantor's financial capabilities. We strive to reduce the exposure of such risks through: (a) reviewing each loan request and renewal individually; (b) using a dual signature approval system; (c) adhering to written loan policies; (d) adhering to SBA written policies and regulations; (e) obtaining independent third party appraisals which are reviewed by the Bank's appraisal department; and (f) obtaining independent credit reviews. In addition, SBA loans normally require monthly installment payments of principal and interest and therefore are continually monitored for past due conditions. In general, the Bank receives and reviews financial statements and other documents of borrowing customers on an ongoing basis during the term of the relationship and responds to any deterioration noted.

        (4)    Consumer Loans.    Consumer loans include personal loans, auto loans, boat loans, home improvement loans, revolving lines of credit and other loans typically made by banks to individual borrowers. The Bank's consumer loan portfolio is subject to certain risks, including: (i) amount of credit offered to consumers in the market; (ii) interest rate increases; and (iii) consumer bankruptcy laws which allow consumers to discharge certain debts. We strive to reduce the exposure to such risks through the direct approval of all consumer loans by: (a) reviewing each loan request and renewal individually; (b) using a dual signature approval system; (c) adhering to written credit policies; and (d) obtaining external independent credit reviews.

        As part of our efforts to achieve long-term stable profitability and respond to a changing economic environment in Southern California and in other areas where we operate, we constantly evaluate a variety of options to augment our traditional focus by broadening the services and products we provide. Possible avenues of growth include more branch locations, expanded days and hours of operation and new types of loan and deposit products. To date, we have not expanded into areas of brokerage, annuity, insurance or similar investment products and services and have concentrated primarily on the core businesses of accepting deposits, making loans and extending credit.

Business Concentrations

        No individual or single group of related accounts is considered material in relation to our total assets or deposits of the Bank, or in relation to the overall business of the Company. However, approximately 77% of our non-covered loan portfolio at December 31, 2010 consisted of real estate-related loans, including construction loans, miniperm loans, commercial real estate mortgage loans and commercial loans secured by commercial real estate. See "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations—Financial Condition—Non-covered Loans." Since our business activities are currently focused primarily in Southern California, with the majority of our business concentrated in Los Angeles, Orange, Riverside, San Bernardino, San Diego, Ventura, Santa Barbara and San Luis Obispo Counties, our results of operations and financial condition are dependent upon the general trends in the Southern California economies and, in particular, the residential and commercial real estate markets. The concentration of our operations in Southern California exposes us to greater risk than other banking companies with a wider geographic base in the event of catastrophes, such as earthquakes, fires and floods in this region. We conduct foreign lending activities including commercial and real estate lending, consisting predominantly of loans to individuals or entities located in Mexico. At December 31, 2010, our foreign loans consisted of approximately 1% of our non-covered loan portfolio. Such foreign loans are denominated in U.S. dollars and most are collateralized by assets located in the United States or are guaranteed or insured by businesses located

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in the United States. We have continued to allow our foreign loan portfolio to repay in the ordinary course of business without making any new privately-insured foreign loans other than those under existing commitments.

Strategic Evolution and Acquisition Strategy

        The Company was organized on October 22, 1999 as a California corporation for the purpose of becoming a bank holding company and to acquire all the outstanding capital stock of Rancho Santa Fe National Bank. Since that time, we have grown through a series of business acquisitions. Most recently, in August 2010 we purchased certain assets and assumed certain liabilities of Los Padres Bank from the FDIC, as receiver of Los Padres Bank.

        The following chart summarizes the acquisitions completed since our inception, some of which are described in more detail below. See also Note 3 of the Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data" in Part II of this Annual Report on Form 10-K for further details regarding our acquisitions.

Security Pacific Bank Deposit Acquisition

        On November 7, 2008, we assumed $427.5 million in deposits from the FDIC as receiver of Security Pacific Bank, or SPB, formerly a Los Angeles-based bank. We assumed all insured and uninsured deposits and paid a 2% premium of approximately $5.1 million related to the non-brokered deposit base of $258 million. The estimated brokered deposits as of the assumption date totaled $169 million. Such deposit assumption was net of acquiring cash, certificates of deposit in other financial institutions, federal funds sold, securities, and loans secured by assumed deposits. As part of the SPB deposit acquisition we also purchased an additional $31 million in loans. The Security Pacific Bank acquisition was made to expand our presence in the Los Angeles area and to gain experience with FDIC-assisted transactions.

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Affinity Bank Acquisition

        On August 28, 2009, we acquired substantially all of the assets of Affinity Bank, including all loans, and assumed substantially all of its liabilities, including the insured and uninsured deposits and excluding certain brokered deposits, from the FDIC in an FDIC-assisted transaction, which we refer to as the Affinity acquisition. Pacific Western (i) acquired $675.6 million in loans, $22.9 million in foreclosed assets, $175.4 million in investments and $371.5 million in cash and other assets, and (ii) assumed $868.2 million in deposits, $305.8 million in borrowings, and $32.6 million in other liabilities. In connection with the Affinity acquisition, the FDIC made a cash payment to Pacific Western of $87.2 million. We entered into a loss sharing agreement with the FDIC, whereby the FDIC agreed to cover a substantial portion of any future losses on acquired loans, other real estate owned and certain investment securities. Under the terms of such loss sharing agreement, the FDIC will absorb 80% of losses and receive 80% of loss recoveries on the first $234 million of losses on covered assets and absorb 95% of losses and receive 95% of loss recoveries on covered assets exceeding $234 million. The loss sharing agreement is in effect for 5 years for commercial assets (non-residential loans, OREO and certain securities) and 10 years for residential loans from the August 28, 2009 acquisition date. The loss recovery provisions are in effect for 8 years for commercial assets and 10 years for residential loans from the acquisition date. We refer to the acquired assets subject to the loss sharing agreement collectively as "covered assets." Affinity was a full service commercial bank headquartered in Ventura, California that operated 10 branch locations in California. We made this acquisition to expand our presence in California.

Los Padres Bank Acquisition

        On August 20, 2010, we acquired certain assets of Los Padres Bank, including all loans, and assumed substantially all of its liabilities, including all deposits, from the FDIC in an FDIC-assisted acquisition, which we refer to as the Los Padres acquisition. Pacific Western (i) acquired $437.1 million in loans, $33.9 million in other real estate owned, $44.3 million in investments, and $261.5 million in cash and other assets and (ii) assumed $752.2 million in deposits, $70.0 million in borrowings, and $1.9 million in other liabilities. In connection with the Los Padres acquisition, the FDIC made a cash payment to Pacific Western of $144.0 million. Other than a deposit premium of $3.4 million, we paid no cash or other consideration to acquire Los Padres. We entered into a loss sharing agreement with the FDIC, whereby the FDIC agreed to cover a substantial portion of any future losses on acquired loans, with the exception of consumer loans, and other real estate owned. Under the terms of such loss sharing agreement, the FDIC is obligated to reimburse the Bank for 80% of losses with respect to the covered assets. The Bank will reimburse the FDIC for 80% of recoveries with respect to losses for which the FDIC paid the Bank 80% reimbursement under the loss sharing agreement. The loss sharing arrangement for single family covered assets and commercial (non-single family) covered assets is in effect for 10 years and 5 years, respectively, from the acquisition date, and the loss recovery provisions are in effect for 10 years and 8 years, respectively, from the acquisition date. We refer to the acquired assets subject to the loss sharing agreement collectively as "covered assets." Los Padres was a federally chartered savings bank headquartered in Solvang, California that operated 14 branches, including 11 branches in California (three in Ventura County, four in Santa Barbara County, and four in San Luis Obispo County) and three branches in Arizona (Maricopa County). After office consolidations in February 2011, there are nine remaining former Los Padres offices with eight in California and one in Arizona. We made this acquisition to expand our presence in the Central Coast of California.

Competition

        The banking business in California, and specifically in the Bank's primary service areas, is highly competitive with respect to originating loans, acquiring deposits and providing other banking services. The market is dominated by commercial banks in Southern California with assets between $500 million

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and $25 billion, including ourselves, and a few banking giants with a large number of offices and full-service operations over a wide geographic area. In recent years, competition has increased from institutions not subject to the same regulatory restrictions as domestic banks and bank holding companies. Those competitors include savings and loan associations, brokerage houses, insurance companies, mortgage companies, credit unions, credit card companies, and other financial and non-financial institutions and entities.

        Economic factors, along with legislative and technological changes, will have an ongoing impact on the competitive environment within the financial services industry. We work to anticipate and adapt to dynamic competitive conditions whether it may be developing and marketing innovative products and services, adopting or developing new technologies that differentiate our products and services, cross marketing, or providing highly personalized banking services. We strive to distinguish ourselves from other community banks and financial services providers in our marketplace by providing an extremely high level of service to enhance customer loyalty and to attract and retain business. However, we can provide no assurance as to the effectiveness of these efforts on our future business or results of operations, as to our continued ability to anticipate and adapt to changing conditions, and as to sufficiently improving our services and/or banking products in order to successfully compete in our primary service areas.

Employees

        As of February 28, 2011, the Company had 929 full time equivalent employees.

Financial and Statistical Disclosure

        Certain of our statistical information is presented within "Item 6. Selected Financial Data," "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations" and "Item 7A. Qualitative and Quantitative Disclosure About Market Risk." This information should be read in conjunction with the consolidated financial statements contained in "Item 8. Financial Statements and Supplementary Data."

Supervision and Regulation

General

        The banking and financial services business in which we engage is highly regulated. Such regulation is intended, among other things, to protect the interests of customers, including depositors. These regulations are not, however, generally charged with protecting the interests of our shareholders or creditors. Described below are the material elements of selected laws and regulations applicable to PacWest and its subsidiaries. The descriptions are not intended to be complete and are qualified in their entirety by reference to the full text of the statutes and regulations described. Changes in applicable law or regulations, and in their application by regulatory agencies, cannot be predicted, but they may have a material effect on the business and results of PacWest and its subsidiaries. The commercial banking business is also influenced by the monetary and fiscal policies of the federal government and the policies of the Federal Reserve Bank, or FRB. The FRB implements national monetary policies (with the dual mandate of price stability and maximum employment) by its open-market operations in United States Government securities, by adjusting the required level of and paying interest on reserves for financial intermediaries subject to its reserve requirements and by varying the discount rates applicable to borrowings by depository institutions. The actions of the FRB in these areas influence the growth of bank loans, investments and deposits and also affect interest rates charged on loans and paid on deposits. Indirectly, such actions may also impact the ability of non-bank financial institutions to compete with the Bank. The nature and impact of any future changes in monetary policies cannot be predicted.

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        The events of the past few years have led to numerous new laws in the United States and internationally for financial institutions. The Dodd-Frank Wall Street Reform and Consumer Protection Act (the "Dodd-Frank Act" or "Dodd-Frank"), which was enacted in July 2010, significantly restructures the financial regulatory regime in the United States, including through the creation of a new systemic risk oversight body, the Financial Stability Oversight Council ("FSOC"). The FSOC will oversee and coordinate the efforts of the primary U.S. financial regulatory agencies (including the FRB, the SEC, the Commodity Futures Trading Commission and the FDIC) in establishing regulations to address financial stability concerns. In addition to the framework for systemic risk oversight implemented through the FSOC, the Dodd-Frank Act broadly affects the financial services industry by creating a resolution authority, mandating higher capital and liquidity requirements, requiring banks to pay increased fees to regulatory agencies, and through numerous other provisions aimed at strengthening the sound operation of the financial services sector. As discussed further throughout this section, many aspects of Dodd-Frank are subject to further rulemaking and will take effect over several years, making it difficult to anticipate the overall financial impact on PacWest or across the industry.

Bank Holding Company Regulation

        As a bank holding company, PacWest is registered with and subject to regulation by the FRB under the Bank Holding Company Act of 1956, as amended, or the BHCA. FRB policy historically has required bank holding companies to act as a source of financial strength to their bank subsidiaries and to commit capital and financial resources to support those subsidiaries in circumstances where it might not otherwise do so. The Dodd-Frank Act codifies this policy as a statutory requirement. Similarly, under the cross-guarantee provisions of the Federal Deposit Insurance Act, the FDIC can hold any FDIC-insured depository institution liable for any loss suffered or anticipated by the FDIC in connection with (i) the default of a commonly controlled FDIC-insured depository institution or (ii) any assistance provided by the FDIC to such a commonly controlled institution. Under the BHCA, we are subject to periodic examination by the FRB. We are also required to file with the FRB periodic reports of our operations and such additional information regarding the Company and its subsidiaries as the FRB may require. Pursuant to the BHCA, we are required to obtain the prior approval of the FRB before we acquire all or substantially all of the assets of any bank or ownership or control of voting shares of any bank if, after giving effect to such acquisition, we would own or control, directly or indirectly, more than 5 percent of such bank.

        Under the BHCA, we may not engage in any business other than managing or controlling banks or furnishing services to our subsidiaries that the FRB deems to be so closely related to banking as "to be a proper incident thereto." We are also prohibited, with certain exceptions, from acquiring direct or indirect ownership or control of more than 5 percent of the voting shares of any company unless the company is engaged in banking activities or the FRB determines that the activity is so closely related to banking as to be a proper incident to banking. The FRB's approval must be obtained before the shares of any such company can be acquired and, in certain cases, before any approved company can open new offices.

        The BHCA and regulations of the FRB also impose certain constraints on the redemption or purchase by a bank holding company of its own shares of stock.

        Additionally, bank holding companies that meet certain eligibility requirements prescribed by the BHCA and elect to operate as financial holding companies may engage in, or own shares in companies engaged in, a wider range of nonbanking activities, including securities and insurance activities and any other activity that the FRB, in consultation with the Secretary of the Treasury, determines by regulation or order is financial in nature, incidental to any such financial activity or complementary to any such financial activity and does not pose a substantial risk to the safety or soundness of depository institutions or the financial system generally. As of the date of this filing, we do not operate as a financial holding company.

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        Our earnings and activities are affected by legislation, by regulations and by local legislative and administrative bodies and decisions of courts in the jurisdictions in which we and the Bank conduct business. For example, these include limitations on the ability of the Bank to pay dividends to us and our ability to pay dividends to our shareholders. It is the policy of the FRB that bank holding companies should pay cash dividends on common stock only out of income available over the past year and only if prospective earnings retention is consistent with the organization's expected future needs and financial condition. The policy provides that bank holding companies should not maintain a level of cash dividends that undermines the bank holding company's ability to serve as a source of strength to its banking subsidiaries. Various federal and state statutory provisions limit the amount of dividends that subsidiary banks and savings associations can pay to their holding companies without regulatory approval. In addition to these explicit limitations, the federal regulatory agencies have general authority to prohibit a banking subsidiary or bank holding company from engaging in an unsafe or unsound banking practice. Depending upon the circumstances, the agencies could take the position that paying a dividend would constitute an unsafe or unsound banking practice. Further, as discussed below under "—Regulation of the Bank", a bank holding company such as the Company is required to maintain minimum ratios of Tier 1 capital and total capital to total risk-weighted assets, and a minimum ratio of Tier 1 capital to total adjusted quarterly average assets as defined in such regulations. The level of our capital ratios may affect our ability to pay dividends. See "Item 5. Market for Registrant's Common Equity and Related Stockholder Matters—Dividends" and Note 19 of the Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data."

        Banking subsidiaries of bank holding companies are also subject to certain restrictions imposed by federal law in dealings with their holding companies and other affiliates. Subject to certain exceptions set forth in the Federal Reserve Act, a bank can make a loan or extend credit to an affiliate, purchase or invest in the securities of an affiliate, purchase assets from an affiliate, accept securities of an affiliate as collateral for a loan or extension of credit to any person or company, issue a guarantee or accept letters of credit on behalf of an affiliate only if the aggregate amount of the above transactions of such subsidiary does not exceed 10 percent of such subsidiary's capital stock and surplus on an individual basis or 20 percent of such subsidiary's capital stock and surplus on an aggregate basis. Such transactions must be on terms and conditions that are consistent with safe and sound banking practices. A bank holding company and its subsidiaries generally may not purchase a "low-quality asset," as that term is defined in the Federal Reserve Act, from an affiliate. Such restrictions also prevent a holding company and its other affiliates from borrowing from a banking subsidiary of the holding company unless the loans are secured by collateral. The Dodd-Frank Act significantly expands the coverage and scope of the limitations on affiliate transactions within a banking organization.

        The FRB has cease and desist powers over parent bank holding companies and non-banking subsidiaries where the action of a parent bank holding company or its non-financial institutions represent an unsafe or unsound practice or violation of law. The FRB has the authority to regulate debt obligations, other than commercial paper, issued by bank holding companies by imposing interest ceilings and reserve requirements on such debt obligations.

Regulation of the Bank

        The Bank is extensively regulated under both federal and state law.

        Various requirements and restrictions under federal and state law affect the operations of the Bank. Federal and state statutes and regulations relate to many aspects of the Bank's operations, including standards for safety and soundness, reserves against deposits, interest payable on certain deposit products, investments, mergers and acquisitions, borrowings, dividends, locations of branch offices, fair lending requirements, Community Reinvestment Act activities and loans to affiliates.

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        Further, each of the Company and the Bank is required to maintain certain levels of capital. The FRB and the FDIC have substantially similar risk-based capital ratio and leverage ratio guidelines for banking organizations. The guidelines are intended to ensure that banking organizations have adequate capital given the risk levels of assets and off-balance sheet financial instruments. Under the guidelines, banking organizations are required to maintain minimum ratios for Tier 1 capital and total capital to risk-weighted assets (including certain off-balance sheet items, such as letters of credit). For purposes of calculating the ratios, a banking organization's assets and some of its specified off-balance sheet commitments and obligations are assigned to various risk categories. A depository institution's or holding company's capital, in turn, is classified in one of three tiers, depending on type:

•

Core Capital (Tier 1).  Tier 1 capital includes common equity, retained earnings, qualifying non-cumulative perpetual preferred stock, a limited amount of qualifying cumulative perpetual stock at the holding company level, minority interests in equity accounts of consolidated subsidiaries, and qualifying trust preferred securities less goodwill, most intangible assets and certain other assets.



•

Supplementary Capital (Tier 2).  Tier 2 capital includes, among other things, perpetual preferred stock and trust preferred securities not meeting the Tier 1 definition, qualifying mandatory convertible debt securities, qualifying subordinated debt, and allowances for possible credit losses, subject to limitations.



•

Market Risk Capital (Tier 3).  Tier 3 capital includes qualifying unsecured subordinated debt.

        The following are the regulatory capital guidelines and the actual capitalization levels for Pacific Western and the Company as of December 31, 2010. Regulatory capital requirements limit the amount of deferred tax assets that may be included when determining the amount of regulatory capital. Deferred tax asset amounts in excess of the calculated limit are deducted from regulatory capital. At December 31, 2010, such amount was $51.0 million. No assurance can be given that the regulatory capital deferred tax asset limitation will not increase in the future. There was no limitation on the Bank's regulatory capital due to deferred tax assets.

        The Company issued subordinated debentures to trusts that were established by us or entities we have acquired, which, in turn, issued trust preferred securities, which totaled $123.0 million at December 31, 2010. These securities are currently included in our Tier I capital for purposes of determining the Company's Tier I and total risk-based capital ratios. The Board of Governors of the Federal Reserve System, which is the holding company's banking regulator, has promulgated a modification of the capital regulations affecting trust preferred securities. Although this modification was scheduled to be effective on March 31, 2009, the Federal Reserve postponed the effective date to March 31, 2011. At that time, the Company will be allowed to include in Tier I capital an amount of trust preferred securities equal to no more than 25% of the sum of all core capital elements, which is generally defined as shareholders' equity less goodwill, net of any related deferred income tax liability. The regulations currently in effect through December 31, 2010, limit the amount of trust preferred securities that can be included in Tier I capital to 25% of the sum of core capital elements without a deduction for goodwill. We have determined that our Tier I capital ratios would remain above the well-capitalized level had the modification of the capital regulations been in effect at December 31, 2010. We expect that our Tier I capital ratios will be at or above the existing well-capitalized levels on

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March 31, 2011, the first date on which the modified capital regulations must be applied. While our existing trust preferred securities are grandfathered, Dodd-Frank precludes new issuances from qualifying as Tier 1 capital.

        The FDIC and FRB risk-based capital guidelines are based upon the 1988 Capital Accord ("Basel I") of the Basel Committee on Banking Supervision (the "Basel Committee"). The Basel Committee is a committee of central banks and bank supervisors/regulators from the major industrialized countries that develops broad policy guidelines that each country's supervisors can use to determine the supervisory policies they apply. After working on revisions for a number of years, in June 2004, the Basel Committee released the final version of its proposed new capital framework, with an update in November 2005 ("Basel II). Basel II proposes two approaches for setting capital standards for credit risk—an internal ratings-based approach tailored to individual institutions' circumstances (which for many asset classes is itself broken into a "foundation" approach and an "advanced" or "A-IRB" approach, the availability of which is subject to additional restrictions) and a standardized approach that bases risk weightings on external credit assessments to a much greater extent than permitted in existing risk-based capital guidelines. Basel II also would set capital requirements for operational risk and refine the existing capital requirements for market risk exposures.

        The U.S. banking and thrift agencies are developing proposed revisions to their existing capital adequacy regulations and standards based on Basel II. In December 2006, the agencies issued a notice of proposed rulemaking setting forth a definitive proposal for implementing Basel II in the United States that would apply only to internationally active banking organizations—defined as those with consolidated total assets of $250 billion or more or consolidated on-balance sheet foreign exposures of $10 billion or more—but that other U.S. banking organizations could elect but would not be required to apply. In November 2007, the agencies adopted a definitive final rule for implementing Basel 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. The final rule was effective on April 1, 2008.

        The Company is not required to comply with Basel II and we have not adopted the Basel II approach.

        In June 2008, the U.S. banking and thrift agencies announced a proposed rule that would provide all non-core banking organizations (that is, banking organizations not required to adopt the advanced approaches) with the option to adopt a way to determine required regulatory capital that is more risk sensitive than the current Basel I-based rules, yet is less complex than the advanced approaches in the final rule. The proposed standardized framework addresses (i) expanding the number of risk-weight categories to which credit exposures may be assigned; (ii) using loan-to-value ratios to risk weight most residential mortgages to enhance the risk sensitivity of the capital requirement; (iii) providing a capital charge for operational risk using the Basic Indicator Approach under the international Basel II capital accord; (iv) emphasizing the importance of a bank's assessment of its overall risk profile and capital adequacy; and (v) providing for comprehensive disclosure requirements to complement the minimum capital requirements and supervisory process through market discipline. This new proposal will replace the agencies' earlier Basel I-A proposal, issued in December 2006.

        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.

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        The Basel III final capital framework, among other things:

•

introduces as a new capital measure "Common Equity Tier 1", or "CET1", specifies that Tier 1 capital consists of CET1 and "Additional Tier 1 capital" instruments meeting specified requirements, 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 expands the scope of the adjustments as compared to existing regulations;



•

when fully phased in on January 1, 2019, requires banks to maintain:



•

as a newly adopted international standard, a minimum ratio of CET1 to risk-weighted assets of at least 4.5%, plus a 2.5% "capital conservation buffer" (which is added to the 4.5% CET1 ratio as that buffer is phased in, effectively resulting in a minimum ratio of CET1 to risk-weighted assets of at least 7%);



•

a minimum ratio of Tier 1 capital to risk-weighted assets of at least 6.0%, plus the capital conservation buffer (which is added to the 6.0% Tier 1 capital ratio as that buffer is phased in, effectively resulting in a minimum Tier 1 capital ratio of 8.5% upon full implementation);



•

a minimum ratio of Total (that is, Tier 1 plus Tier 2) capital to risk-weighted assets of at least 8.0%, plus the capital conservation buffer (which is added to the 8.0% total capital ratio as that buffer is phased in, effectively resulting in a minimum total capital ratio of 10.5% upon full implementation); and



•

as a newly adopted international standard, a minimum leverage ratio of 3%, calculated as the ratio of Tier 1 capital to balance sheet exposures plus certain off-balance sheet exposures (as the average for each quarter of the month-end ratios for the quarter); and



•

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, that would be a CET1 add-on to the capital conservation buffer in the range of 0% to 2.5% when fully implemented (potentially resulting in total buffers of between 2.5% and 5%).

        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 (or below the combined capital conservation buffer and countercyclical capital buffer, when the latter is applied) will face constraints on dividends, equity repurchases and compensation based on the amount of the short fall.

        The implementation of the Basel III final framework will commence January 1, 2013. On that date, banking institutions will be required to meet the following minimum capital ratios:

•

3.5% CET1 to risk-weighted assets;



•

4.5% Tier 1 capital to risk-weighted assets; and



•

8.0% Total capital to risk-weighted assets.

        The Basel III final framework provides for a number of new deductions from and adjustments to CET1. These include, for example, the requirement that mortgage servicing rights, deferred tax assets dependent upon future taxable income and significant investments in non-consolidated financial entities be deducted from CET1 to the extent that any one such category exceeds 10% of CET1 or all such categories in the aggregate exceed 15% of CET1.

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

        The U.S. banking agencies have indicated informally that they expect to propose regulations implementing Basel III in mid-2011 with final adoption of implementing regulations in mid-2012. Given that the Basel III rules are subject to change, and the scope and content of capital regulations that the U.S. banking agencies may adopt under Dodd-Frank is uncertain, we cannot be certain of the impact new capital regulations will have on our capital ratios.

        Historically, regulation and monitoring of bank and bank holding company liquidity has been addressed as a supervisory matter, both in the U.S. and internationally, 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. One test, referred to as the liquidity coverage ratio ("LCR"), is designed to ensure that the banking entity maintains an adequate level of unencumbered high-quality liquid assets equal to the entity's expected net cash outflow for a 30-day time horizon (or, if greater, 25% of its expected total cash outflow) under an acute liquidity stress scenario. The other, referred to as the net stable funding ratio ("NSFR"), is designed to promote more medium- and long-term funding of the assets and activities of banking entities over a one-year time horizon. These requirements will incent banking entities to increase their holdings of U.S. Treasury securities and other sovereign debt as a component of assets and increase the use of long-term debt as a funding source. The LCR would be implemented subject to an observation period beginning in 2011, but would not be introduced as a requirement until January 1, 2015, and the NSFR would not be introduced as a requirement until January 1, 2018. These new standards are subject to further rulemaking and their terms may well change before implementation.

Prompt Corrective Action

        The Federal Deposit Insurance Corporation Improvement Act, or FDICIA, requires each federal banking agency to take prompt corrective action to resolve the problems of insured depository institutions, including but not limited to those that fall below one or more prescribed minimum capital ratios. Pursuant to FDICIA, the FDIC promulgated regulations defining the following five categories in which an insured depository institution will be placed, based on the level of its capital ratios: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized and critically undercapitalized. Under the prompt corrective action provisions of FDICIA, an insured depository institution generally will be classified as undercapitalized if its total risk-based capital is less than 8% or its Tier 1 risk-based capital or leverage ratio is less than 4%. An institution that, based upon its capital levels, is classified as "well capitalized", "adequately capitalized" or "undercapitalized" may be treated as though it were in the next lower capital category if the appropriate federal banking agency, after notice and opportunity for hearing, determines that an unsafe or unsound condition or an unsafe or unsound practice warrants such treatment. At each successive lower capital category, an insured depository institution is subject to more restrictions and prohibitions, including restrictions on growth, restrictions on interest rates paid on deposits, prohibitions on payment of dividends and restrictions on the acceptance of brokered deposits. Furthermore, if a bank is classified in one of the undercapitalized categories, it is required to submit a capital restoration plan to the federal bank regulator, and the holding company must guarantee the performance of that plan.

        In addition to measures taken under the prompt corrective action provisions, commercial banking organizations may be subject to potential enforcement actions by the federal or state banking agencies for unsafe or unsound practices in conducting their businesses or for violations of any law, rule,

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regulation or any condition imposed in writing by the agency or any written agreement with the agency. Enforcement actions may include the imposition of a conservator or receiver, the issuance of a cease-and-desist order that can be judicially enforced, the termination of insurance for deposits (in the case of a depository institution), the imposition of civil money penalties, the issuance of directives to increase capital, the issuance of formal and informal agreements, the issuance of removal and prohibition orders against institution-affiliated parties. The enforcement of such actions through injunctions or restraining orders may be based upon a judicial determination that the agency would be harmed if such equitable relief was not granted.

Deposit Insurance

        Pacific Western is a state-chartered, "non-member" bank and therefore is regulated by the California Department of Financial Institutions, or DFI, and the FDIC. Pacific Western is also an FDIC insured financial institution whereby the FDIC provides deposit insurance for a certain maximum dollar amount per customer.

        The Bank, as is the case with all FDIC insured banks, is subject to deposit insurance assessments as determined by the FDIC. Historically, the FDIC imposed insurance premiums based on the amount of deposits held and a risk matrix that takes into account, among other factors, a bank's capital level and supervisory rating. The Dodd-Frank Act requires the FDIC to amend its regulations to determine insurance assessments based on the average consolidated assets less the average tangible equity of the insured depository institution during the assessment period. The proposed regulations could increase the assessments paid by the Bank.

        In late 2008, in an effort to strengthen confidence and encourage liquidity in the banking system, the FDIC temporarily increased the maximum amount of deposit insurance to $250,000 per customer and adopted a number of programs, including the Transaction Account Guarantee Program. The Transaction Account Guarantee Program guaranteed the entire balance of non-interest bearing deposit transaction accounts through December 31, 2010. Institutions participating in the Transaction Account Guarantee Program were charged a 10-basis point fee on the balance of non-interest bearing deposit transaction accounts exceeding the existing deposit insurance limit of $250,000. The cost to the Bank for participating in this program was $794,000 for 2010 and $452,000 for 2009. Under Dodd-Frank, the $250,000 maximum amount was made permanent, and the unlimited protection for noninterest-bearing transaction accounts was extended to December 31, 2012 and to all insured depository institutions.

        On November 12, 2009, the FDIC required insured depository institutions to prepay, on December 30, 2009, their estimated quarterly assessments for the fourth quarter of 2009, and for all of 2010, 2011, and 2012. The amount of Pacific Western's FDIC assessment prepayment was $19.5 million, which we paid on December 30, 2009. In addition, the FDIC imposed a special assessment on all depository institutions in the second quarter of 2009; such assessment was $2.0 million for the Bank.

        The 2009 prepayments and special assessment for FDIC insurance are in contrast to the lower FDIC insurance assessment expense for Pacific Western in 2008 and 2007. Because of favorable loss experience and a healthy reserve ratio in the deposit insurance fund of the FDIC, well-capitalized and well-managed banks, including Pacific Western, paid minimal premiums for FDIC insurance during 2008 and 2007. A deposit premium refund, in the form of credit offsets, was given to banks that were in existence on December 31, 1996 and paid deposit insurance premiums prior to that date. Pacific Western utilized its credit offset to eliminate a portion of its 2008 and nearly all of its 2007 FDIC insurance assessments.

        Based on the current FDIC insurance assessment methodology and including our participation in the Transaction Account Guarantee Program, our FDIC insurance assessment was $8.1 million for 2010.

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Depositor Preference

        The Federal Deposit Insurance Act provides that, in the event of the "liquidation or other resolution" of an insured depository institution, the claims of depositors of the institution, including the claims of the FDIC as subrogee of insured depositors, and certain claims for administrative expenses of the FDIC as a receiver, will have priority over other general unsecured claims against the institution. If an insured depository institution fails, insured and uninsured depositors, along with the FDIC, will have priority in payment ahead of unsecured, non-deposit creditors, including the parent bank holding company, with respect to any extensions of credit they have made to such insured depository institution.

Sarbanes-Oxley Act

        As a publicly traded company, we are subject to the Sarbanes-Oxley Act of 2002 ("Sarbanes-Oxley Act"). The principal provisions of the Sarbanes-Oxley Act, many of which have been implemented or interpreted through regulations, provide for and include, among other things: (i) the creation of an independent accounting oversight board; (ii) auditor independence provisions that restrict non-audit services that accountants may provide to their audit clients; (iii) additional corporate governance and responsibility measures, including the requirement that the chief executive officer and chief financial officer of a public company certify financial statements; (iv) the forfeiture of bonuses or other incentive-based compensation and profits from the sale of an issuer's securities by directors and senior officers in the twelve month period following initial publication of any financial statements that later require restatement; (v) an increase in the oversight of, and enhancement of certain requirements relating to, audit committees of public companies and how they interact with the Company's independent auditors; (vi) requirements that audit committee members must be independent and are barred from accepting consulting, advisory or other compensatory fees from the issuer; (vii) requirements that companies disclose whether at least one member of the audit committee is a "financial expert" (as such term is defined by the SEC) and if not discussed, why the audit committee does not have a financial expert; (viii) expanded disclosure requirements for corporate insiders, including accelerated reporting of stock transactions by insiders and a prohibition on insider trading during pension blackout periods; (ix) a prohibition on personal loans to directors and officers, except certain loans made by insured financial institutions on nonpreferential terms and in compliance with other bank regulatory requirements; (x) disclosure of a code of ethics and filing a Form 8-K for a change or waiver of such code; (xi) a range of enhanced penalties for fraud and other violations; and (xii) expanded disclosure and certification relating to an issuer's disclosure controls and procedures and internal controls over financial reporting.

        As a result of the Sarbanes-Oxley Act, and its implementing regulations, we have incurred substantial costs to interpret and ensure ongoing compliance with the law and its regulations. Future changes in the laws, regulation, or policies that impact us cannot necessarily be predicted and may have a material effect on our business and earnings.

USA PATRIOT Act

        The Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001, or the PATRIOT Act, designed to deny terrorists and others the ability to obtain access to the United States financial system, has significant implications for depository institutions, brokers, dealers and other businesses involved in the transfer of money. The PATRIOT Act, as implemented by various federal regulatory agencies, requires financial institutions, including the Company, to establish and implement policies and procedures with respect to, among other matters, anti-money laundering, compliance, suspicious activity and currency transaction reporting and due diligence on customers. The PATRIOT Act and its underlying regulations permit information sharing for counter-terrorist purposes between federal law enforcement agencies and financial institutions, as well as among financial institutions, subject to certain conditions, and require the FRB, the FDIC and

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other federal banking agencies to evaluate the effectiveness of an applicant in combating money laundering activities when considering applications filed under Section 3 of the BHCA or the Bank Merger Act. We regularly evaluate and continue to augment our systems and procedures to continue to comply with the PATRIOT Act and other anti-money laundering initiatives. We believe that the ongoing cost of compliance with the PATRIOT Act is not likely to be material to the Company. Failure of a financial institution to maintain and implement adequate programs to combat money laundering and terrorist financing, or to comply with all of the relevant laws or regulations, could have serious legal and reputational consequences for the institution.

Office of Foreign Assets Control Regulation

        The United States has imposed economic sanctions that affect transactions with designated foreign countries, nationals and others. These are typically known as the "OFAC" rules based on their administration by the U.S. Treasury Department Office of Foreign Assets Control ("OFAC"). The OFAC-administered sanctions targeting countries take many different forms. Generally, however, they contain one or more of the following elements: (i) restrictions on trade with or investment in a sanctioned country, including prohibitions against direct or indirect imports from and exports to a sanctioned country and prohibitions on "U.S. persons" engaging in financial transactions relating to making investments in, or providing investment-related advice or assistance to, a sanctioned country; and (ii) a blocking of assets in which the government or specially designated nationals of the sanctioned country have an interest, by prohibiting transfers of property subject to U.S. jurisdiction (including property in the possession or control of U.S. persons). Blocked assets (e.g., property and bank deposits) cannot be paid out, withdrawn, set off or transferred in any manner without a license from OFAC. Failure to comply with these sanctions could have serious legal and reputational consequences.

Community Reinvestment Act

        The Community Reinvestment Act of 1977, or the CRA, generally requires insured depository institutions to identify the communities they serve and to make loans and investments, offer products, and provide services designed to meet the credit needs of these communities. The CRA also requires banks to maintain comprehensive records of its CRA activities to demonstrate how it is meeting the credit needs of their communities; these documents are subject to periodic examination by the FDIC. During these examinations, the FDIC rates such institutions' compliance with CRA as "Outstanding," "Satisfactory," "Needs to Improve" or "Substantial Noncompliance." The CRA requires the FDIC to take into account the record of a bank in meeting the credit needs of the entire communities served, including low-and moderate income neighborhoods, in determining such rating. Failure of an institution to receive at least a "Satisfactory" rating could inhibit such institution or its holding company from undertaking certain activities, including acquisitions. The Bank received a CRA rating of "Satisfactory" as of its most recent examination.

Customer Information Security

        The FRB and other bank regulatory agencies have adopted final guidelines for safeguarding confidential, personal customer information. These guidelines require each financial institution, under the supervision and ongoing oversight of its board of directors or an appropriate committee thereof, to create, implement and maintain a comprehensive written information security program designed to ensure the security and confidentiality of customer information, protect against any anticipated threats or hazard to the security or integrity of such information and protect against unauthorized access to or use of such information that could result in substantial harm or inconvenience to any customer. We have adopted a customer information security program to comply with such requirements.

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Privacy

        The Gramm-Leach-Bliley Act of 1999 and the California Financial Information Privacy Act require financial institutions to implement policies and procedures regarding the disclosure of nonpublic personal information about consumers to non-affiliated third parties. In general, the statutes require explanations to consumers on policies and procedures regarding the disclosure of such nonpublic personal information, and, except as otherwise required by law, prohibit disclosing such information except as provided in the Bank's policies and procedures. Pacific Western has implemented privacy policies addressing these restrictions which are distributed regularly to all existing and new customers of the Bank.

Legislative and Regulatory Initiatives

        From time to time, various legislative and regulatory initiatives are introduced in the U.S. 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 our operating environment in substantial and unpredictable ways. If enacted, such legislation could increase or decrease the cost of doing business, limit or expand permissible activities or affect the competitive balance among banks, savings associations, credit unions, and other financial institutions. We cannot predict whether any such legislation will be enacted, and, if enacted, the effect that it, or any implementing regulations, would have on our financial condition, results of operations or cash flows. A change in statutes, regulations or regulatory policies applicable to the Company or any of its subsidiaries could have a material effect on our business.

Hazardous Waste Clean-Up and Climate-Related Risk

        Our primary exposure to environmental laws is through our lending activities and through properties or businesses we may own, lease or acquire since we are not involved in any business that manufactures, uses or transports chemicals, waste, pollutants or toxins that might have a material adverse effect on the environment. Based on a general survey of the Bank's loan portfolio, conversations with local appraisers and the type of lending currently and historically done by the Bank, we are not aware of any potential liability for hazardous waste contamination that would be reasonably likely to have a material adverse effect on the Company as of February 16, 2010. In addition, we are not aware of any physical or regulatory consequence resulting from climate change that would have a material adverse effect upon the Company.

Available Information

        We maintain an Internet website at www.pacwestbancorp.com, and a website for Pacific Western at www.pacificwesternbank.com. At www.pacwestbancorp.com and via the "Investor Relations" link at the Bank's website, our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to such reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act are available, free of charge, as soon as reasonably practicable after such forms are electronically filed with, or furnished to, the SEC. The public may read and copy any materials we file with the SEC at the SEC's Public Reference Room, located at 100 F Street, NE, Washington, D.C. 20549. The public may obtain information on the operation of the Public Reference Room by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet website at http://www.sec.gov that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC. You may obtain copies of the Company's filings on the SEC site. These documents may also be obtained in print upon request by our stockholders to our Investor Relations Department.

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        We have adopted a written code of ethics that applies to all directors, officers and employees of the Company, including our principal executive officer and senior financial officers, in accordance with Section 406 of the Sarbanes-Oxley Act of 2002 and the rules of the Securities and Exchange Commission promulgated thereunder. The code of ethics, which we call our Code of Business Conduct and Ethics, is available on our corporate website, www.pacwestbancorp.com in the section entitled "Corporate Governance." In the event that we make changes in, or provide waivers from, the provisions of this code of ethics that the SEC requires us to disclose, we intend to disclose these events on our corporate website in such section. In the Corporate Governance section of our corporate website, we have also posted the charters for our Audit Committee and our Compensation, Nominating and Governance Committee, as well as our Corporate Governance Guidelines. In addition, information concerning purchases and sales of our equity securities by our executive officers and directors is posted on our website.

        Our Investor Relations Department can be contacted at PacWest Bancorp, 275 N. Brea Blvd., Brea, CA 92821, Attention: Investor Relations, telephone (714) 671-6800, or via e-mail to investor-relations@pacwestbancorp.com.

        All website addresses given in this document are for information only and are not intended to be an active link or to incorporate any website information into this document.

Forward-Looking Information

        This Annual Report on Form 10-K contains certain forward-looking information about the Company, which statements are intended to be covered by the safe harbor for "forward-looking statements" provided by the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical fact are forward-looking statements. Such statements involve inherent risks and uncertainties, many of which are difficult to predict and are generally beyond the control of the Company. We caution readers that a number of important factors could cause actual results to differ materially from those expressed in, implied or projected by, such forward-looking statements. Risks and uncertainties include, but are not limited to:

•

lower than expected revenues;



•

credit quality deterioration or pronounced and sustained reduction in real estate market values resulting in an increase in the allowance for credit losses and a reduction in earnings;



•

increased competitive pressure among depository institutions;



•

the Company's ability to complete future acquisitions and to successfully integrate such acquired entities or achieve expected benefits, synergies and/or operating efficiencies within expected time-frames or at all;



•

the possibility that personnel changes will not proceed as planned;



•

the cost of additional capital is more than expected;



•

a change in the interest rate environment reduces interest margins;



•

asset/liability repricing risks and liquidity risks;



•

pending legal matters may take longer or cost more to resolve or may be resolved adversely to the Company;



•

general economic conditions, either nationally or in the market areas in which the Company does or anticipates doing business, are less favorable than expected;

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•

environmental conditions, including natural disasters, may disrupt our business, impede our operations, negatively impact the values of collateral securing the Company's loans or impair the ability of our borrowers to support their debt obligations;



•

the economic and regulatory effects of the continuing war on terrorism and other events of war, including the conflicts in Iraq, Afghanistan, and neighboring countries;



•

legislative or regulatory requirements or changes adversely affecting the Company's business;



•

changes in the securities markets; and



•

regulatory approvals for any capital activities or payment of dividends cannot be obtained, or are not obtained on terms expected or on the anticipated schedule.

        If any of these risks or uncertainties materializes or if any of the assumptions underlying such forward-looking statements proves to be incorrect, our results could differ materially from those expressed in, implied or projected by, such forward-looking statements. Therefore, readers should be mindful that forward-looking statements are not guarantees of future performance and that they are subject to known and unknown risks and uncertainties that are difficult to predict. Except as required by law, we undertake no, and hereby disclaim any, obligation to update any forward-looking statements, whether as a result of new information, changed circumstances or otherwise. For additional information concerning risks and uncertainties related to us and our operations, please refer to Items 1 through 7A of this Annual Report on Form 10-K.

ITEM 1A.    RISK FACTORS

        Ownership of our common stock involves risk. You should carefully consider, in addition to the other information set forth herein, the following risk factors.

Our business has been and may continue to be adversely affected by current conditions in the financial markets and economic conditions generally.

        From December 2007 through June 2009, the U.S. economy was in recession and economic recovery through 2010 has been sluggish. As a result, the global financial markets have undergone and may continue to experience pervasive and fundamental disruptions. In some cases, the markets have produced downward pressure on stock prices and credit availability for certain issuers without regard to those issuers' underlying financial strength. While economic conditions have recently shown signs of improvement, the sustainability of an economic recovery is uncertain as business activity across a wide range of industries continues to face difficulties due to the lack of consumer spending and sustained high levels of unemployment.

        A sustained weakness or further weakening in business and economic conditions generally or specifically in the principal markets in which we do business could have one or more of the following adverse effects on our business:

•

a decrease in the demand for loans and other products and services offered by us;



•

a decrease in deposit balances due to overall reductions in the accounts of customers;



•

a decrease in the value of our loans or other assets secured by consumer or commercial real estate;



•

an impairment of certain intangible assets; or



•

an increase in the number of borrowers who become delinquent, file for protection under bankruptcy laws or default on their loans or other obligations to us. An increase in the number of delinquencies, bankruptcies or defaults could result in a higher level of nonperforming assets, net charge-offs and provision for credit losses.

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        Overall, the economic downturn has had an adverse effect on our business, and there can be no assurance that an economic recovery will be sustainable in the near term. Until conditions improve, we expect our business, financial condition and results of operations to be adversely affected.

Changes in economic conditions, in particular a worsening of the economic slowdown in Southern California, could materially and adversely affect our business.

        Our business is directly impacted by factors such as economic, political and market conditions, broad trends in industry and finance, legislative and regulatory changes, and changes in government monetary and fiscal policies and inflation, all of which are beyond our control. The current economic conditions have caused a lack of consumer confidence, increased market volatility and widespread reduction of business activity generally. These circumstances may lead to a renewed increase in nonaccrual and classified loans, which generally results in a provision for credit losses and in turn reduces the Company's net earnings. The State of California continues to face fiscal challenges, the long-term effects of which on the State's economy cannot be predicted. A further deterioration in the economic conditions, whether caused by national or local concerns, could materially and adversely affect our business. In particular, further deterioration of the economic conditions in Southern California could result in the following consequences, any of which could materially and adversely affect our business: loan delinquencies may increase; problem assets and foreclosures may increase; demand for our products and services may decrease; low cost or noninterest bearing deposits may decrease; and collateral for loans made by us, especially real estate, may decline in value, in turn reducing customers' borrowing power, and reducing the value of assets and collateral associated with our existing loans. Until conditions provide for sustainable improvement, we expect our business, financial condition and results of operations to be adversely affected.

Further disruptions in the real estate market could materially and adversely affect our business.

        There has been a slow-down in the real estate market due to negative economic trends and credit market disruption, the impacts of which are not yet completely known or quantified. At December 31, 2010, 64% of our non-covered loans were secured by commercial real estate, 3% were secured by commercial real estate construction projects, 2% were secured by residential real estate construction projects and 8% were secured by residential real estate. We have observed in the marketplace tighter credit underwriting and higher premiums on liquidity, both of which may continue to place downward pressure on real estate values. Any further downturn in the real estate market could materially and adversely affect our business because a significant portion of our non-covered loans are secured by real estate. Our ability to recover on defaulted non-covered loans by selling the real estate collateral would then be diminished and we would be more likely to suffer losses on defaulted non-covered loans. Substantially all of our real property collateral is located in Southern California. If there is a further decline in real estate values, especially in Southern California, the collateral for our non-covered loans would provide less security. Real estate values could be affected by, among other things, a worsening of the economic conditions, an increase in foreclosures, a decline in home sale volumes, an increase in interest rates, high levels of unemployment, earthquakes and other natural disasters particular to California.

Our business is subject to interest rate risk, and variations in interest rates may materially and adversely affect our financial performance.

        Changes in the interest rate environment may reduce our profits. It is expected that we will continue to realize income from the differential or "spread" between the interest earned on loans, securities and other interest earning assets, and 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. Changes in market

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interest rates generally affect loan volume, loan yields, funding sources and funding costs. Our net interest spread depends on many factors that are partly or completely out of our control, including competition, federal economic monetary and fiscal policies, and general economic conditions.

        While an increase in the general level of interest rates may increase our loan yield, it may adversely affect the ability of certain borrowers with variable rate loans to pay the interest on and principal of their obligations. In addition, an increase in market interest rates on loans is generally associated with a lower volume of loan originations, which may reduce earnings. Following an increase in the general level of interest rates, our ability to maintain a positive net interest spreads is dependent on our ability to increase our loan offering rates, replace loan maturities with new originations, minimize increases on our deposit rates, and maintain an acceptable level and mix of funding. We cannot provide assurances that we will be able to increase our loan offering rates and continue to originate loans due to the competitive landscape in which we operate. Additionally, we cannot provide assurances that we can minimize the increases in our deposit rates while maintaining an acceptable level of deposits. Finally, we cannot provide any assurances that we can maintain our current levels of noninterest bearing deposits as customers may seek higher yielding products when rates increase.

        Following a decline in the general level of interest rates, our ability to maintain a positive net interest spread is dependent on our ability to reduce the interest paid on deposits, borrowings, and other interest bearing liabilities. We cannot provide assurance that we would be able to lower the rates paid on deposit accounts to support our liquidity requirements as lower rates may result in deposit outflows.

        Accordingly, changes in levels of market interest rates could materially and adversely affect our net interest spread, asset quality, loan origination volume, liquidity, and overall profitability. We cannot assure you that we can minimize our interest rate risk.

We face strong competition from financial services companies and other companies that offer banking services which could materially and adversely affect our business.

        We conduct our banking operations primarily in Southern California. Increased competition in our market may result in reduced loans and deposits. Ultimately, we may not be able to compete successfully against current and future competitors. Many competitors offer the same banking services that we offer in our service area. These competitors include national banks, regional banks and other community banks. We also face competition from many other types of financial institutions, including without limitation, savings and loan institutions, finance companies, brokerage firms, insurance companies, credit unions, mortgage banks and other financial intermediaries. In particular, our competitors include several major financial companies whose greater resources may afford them a marketplace advantage by enabling them to maintain numerous banking locations and ATMs and conduct extensive promotional and advertising campaigns.

        Additionally, banks and other financial institutions with larger capitalization and financial intermediaries not subject to bank regulatory restrictions have larger lending limits and are thereby able to serve the credit needs of larger customers. Areas of competition include interest rates for loans and deposits, efforts to obtain deposits, and range and quality of products and services provided, including new technology driven products and services. Technological innovation continues to contribute to greater competition in domestic and international financial services markets as technological advances enable more companies to provide financial services. We also face competition from out-of-state financial intermediaries that have opened production offices or that solicit deposits in our market areas. Should competition in the financial services industry intensify, our ability to market our products and services may be adversely affected. If we are unable to attract and retain banking customers, we may be unable to grow or maintain the levels of our loans and deposits and our results of operations and financial condition may be adversely affected.

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        Competition from financial institutions seeking to maintain adequate liquidity places upward pressure on the rates paid on certain deposit accounts relative to the level of market interest rates during times of both decreasing and increasing market liquidity. To maintain both attractive and adequate levels of liquidity, without exhausting secondary sources of liquidity, we may incur increased deposit costs.

        Several rating agencies publish unsolicited ratings of the financial performance and relative financial health of many banks, including Pacific Western, based on publicly available data. As these ratings are publicly available, a decline in the Bank's ratings may result in deposit outflows or the inability of the Bank to raise deposits in the secondary market as broker-dealers and depositors may use such ratings in deciding where to deposit their funds.

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

        We may need to raise additional capital in the future to provide us with sufficient capital resources and liquidity to meet our commitments and business needs. As a publicly traded company, a likely source of additional funds is the capital markets, accomplished generally through the issuance of equity, both common and preferred stock, and the issuance of subordinated debentures. Our 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 our control, and our financial performance. The current economic conditions and the loss of confidence in financial institutions may increase our cost of funding and limit our access to some of our customary sources of liquidity, including, but not limited to, the capital markets, inter-bank borrowings, repurchase agreements and borrowings from the discount window of the Federal Reserve.

        We cannot assure you that access to such capital and liquidity will be available to us on acceptable terms or at all. Any occurrence that may limit our access to the capital markets, such as a decline in the confidence of debt purchasers, or depositors of the Bank or counterparties participating in the capital markets may materially and adversely affect our capital costs and our ability to raise capital and, in turn, our liquidity. An inability to raise additional capital on acceptable terms when needed could have a materially adverse effect on our business.

We are subject to extensive regulation which could materially and adversely affect our business.

        Our operations are subject to extensive regulation by federal and state governmental authorities, and we are subject to various laws and judicial and administrative decisions imposing requirements and restrictions on part or all of our operations. The Dodd-Frank Act, enacted in July 2010, instituted major changes to the banking and financial institutions regulatory regimes in light of the recent performance of and government intervention in the financial services sector. Regulations affecting banks and other financial institutions, such as the Dodd-Frank Act, are undergoing continuous review and change frequently; the ultimate effect of such changes cannot be predicted. Because our business is highly regulated, compliance with such regulations and laws may increase our costs and limit our ability to pursue business opportunities. Also, participation in specific government stabilization programs may subject us to additional restrictions. There can be no assurance that proposed laws, rules and regulations will not be adopted in the future, which could (i) make compliance much more difficult or expensive, (ii) restrict our ability to originate, broker or sell loans or accept certain deposits, (iii) further limit or restrict the amount of commissions, interest or other charges earned on loans originated or sold by us, or (iv) otherwise materially and adversely affect our business or prospects for business.

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        The recently enacted Dodd-Frank Act will have material implications for the Company and the entire financial services industry. Among other things it will or potentially could:

•

affect the levels of capital and liquidity with which we must operate and how we plan capital and liquidity levels;



•

subject us to new and/or higher fees paid to various regulatory entities, including but not limited to deposit insurance fees to the FDIC;



•

impact our ability to invest in certain types of entities or engage in certain activities;



•

restrict the nature of our incentive compensation programs for executive officers;



•

subject us to a new Consumer Financial Protection Bureau, with very broad rule-making and enforcement authorities; and



•

subject us to new and different litigation and regulatory enforcement risks.

        As the Dodd-Frank Act requires that many studies be conducted and that hundreds of regulations be written in order to fully implement it, the full impact of this legislation on us, our business strategies, and financial performance cannot be known at this time, and may not be known for a number of years. However, these impacts are expected to be substantial and some of them are likely to adversely affect us and our financial performance. The Dodd-Frank Act and related regulations may also require us to invest significant management attention and resources to make any necessary changes, and could therefore also adversely affect our business, financial condition and results of operations.

        Additionally, in order to conduct certain activities, including acquisitions, we are required to obtain regulatory approval. There can be no assurance that any required approvals can be obtained, or obtained without conditions or on a timeframe acceptable to us. For more information, please see the section entitled "Item 1. Business—Supervision and Regulation" above.

The recent repeal of federal prohibitions on payment of interest on demand deposits could increase our 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 could commence offering interest on demand deposits to compete for clients. We do not yet know what interest rates other institutions may offer. Our interest expense will increase and our net interest margin will decrease if the Bank begins offering interest on demand deposits to attract additional customers or maintain current customers, which could have a material adverse effect on our business, financial condition and results of operations.

Emergency measures designed to stabilize the U.S. financial system are beginning to wind down.

        Since the middle of 2008, in addition to the programs initiated under the Emergency Economic Stabilization Act of 2008, other regulators have taken steps to attempt to stabilize and add liquidity to the financial markets. Some of these programs have begun to expire and the impact of the expiration of these programs on the financial industry and the economic recovery is unknown. A slowdown in or reversal of the economic recovery could have a material adverse effect on our business, financial condition and results of operations.

Increases in or required prepayments of FDIC insurance premiums may adversely affect our earnings.

        Since 2008, higher levels of bank failures have dramatically increased resolution costs of the FDIC and depleted the deposit insurance fund. In addition, the FDIC instituted temporary programs, some of

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which were made permanent by the Dodd-Frank Act, to further insure customer deposits at FDIC insured banks, which have placed additional stress on the deposit insurance fund.

        In order to maintain a strong funding position and restore reserve ratios of the deposit insurance fund, the FDIC has increased assessment rates of insured institutions. In addition, on November 12, 2009, the FDIC adopted a rule requiring banks to prepay three years' worth of premiums to replenish the depleted insurance fund.

        Historically, the FDIC utilized a risk-based assessment system that imposed insurance premiums based upon a risk matrix that takes into account several components including but not limited to the bank's capital level and supervisory rating. The Dodd-Frank Act requires the FDIC to amend its regulations to base insurance assessments on the average consolidated assets less the average tangible equity of the insured depository institution during the assessment period. The FDIC has proposed implementing regulations which could increase the assessments paid by the Bank. In addition, the FDIC has proposed regulations that would change the way the deposit insurance assessment rate is applied to banks to a system that is risk-based.

        We are generally unable to control the amount of premiums that we are required to pay for FDIC insurance. Any future increases in or required prepayments of FDIC insurance premiums may adversely affect our financial condition or results of operations.

We are exposed to transactional, country and legal risk related to our foreign loans that is in addition to risks we face on loans to U.S. based borrowers.

        Approximately 1% of our non-covered loan portfolio is represented by credit we extend and loans we make to business located outside the United States, predominantly in Mexico. These loans, which include commercial loans, real estate loans and credit extensions for the financing of international trade, are subject to risks in addition to risks we face with our loans to businesses located in the United States including, but not limited to transaction risk, country risk and legal risk. While these loans are denominated in U.S. dollars, the ability of the borrower to repay may be affected by fluctuations in the borrower's home country currency relative to the U.S. dollar. Additionally, while most of our foreign loans are insured by U.S.-based institutions, guaranteed by a U.S.-based entity, or collateralized with U.S.-based assets or real property, our ability to collect in the event of default is subject to a number of conditions, as well as deductibles and co-payments with respect to insurance, and we may not be successful in obtaining partial or full repayment or reimbursement from the insurers. Furthermore, foreign laws may restrict our ability to foreclose on, take a security interest in, or seize collateral located in the foreign country.

We are exposed to risk of environmental liabilities with respect to properties to which we take title.

        In the course of our business, we may own or foreclose and take title to real estate, and could be subject to environmental liabilities with respect to these properties. We may be held liable to a governmental entity or to third parties for property damage, personal injury, investigation and clean-up costs incurred by these parties in connection with environmental contamination, or may be required to investigate or clean up hazardous or toxic substances, or chemical releases at a property. The costs associated with investigation or remediation activities could be substantial. In addition, as the owner or former owner of a contaminated site, we may be subject to common law claims by third parties based on damages and costs resulting from environmental contamination emanating from the property. If we ever become subject to significant environmental liabilities, our business, financial condition, liquidity and results of operations could be materially and adversely affected.

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We may not pay dividends on common stock.

        Our stockholders are only entitled to receive such dividends as our Board of Directors may declare out of funds legally available for such payments. Although we have historically declared cash dividends on our common stock, we are not required to do so and may reduce or eliminate our common stock dividend in the future. Our ability to pay dividends to our stockholders is subject to the restrictions set forth in Delaware law, by our federal regulator, and by certain covenants contained in the indentures governing the trust preferred securities issued by us or entities we have acquired. Notification to the FRB is also required prior to our declaring and paying a cash dividend to our stockholders during any period in which our quarterly net earnings are insufficient to fund the dividend amount. We may not pay a dividend should the FRB object until such time as we receive approval from the FRB or no longer need to provide notice under applicable regulations. See "Item 5. Market for Registrant's Common Equity and Related Stockholder Matters—Dividends" of this Annual Report on Form 10-K for more information on these restrictions. In addition, we may be restricted by applicable law or regulation or actions taken by our regulators, or as a result of our participation in any specific government stabilization programs, now or in the future, from paying dividends to our stockholders. Accordingly, we cannot assure you that we will continue paying dividends on our common stock at current levels or at all.

The primary source of our income from which we pay dividends is the receipt of dividends from the Bank.

        The availability of dividends from the Bank is limited by various statutes and regulations. It is possible, depending upon the financial condition of the Bank and other factors, that the FRB, the FDIC and/or the DFI could assert that payment of dividends or other payments is an unsafe or unsound practice, or that such regulatory authority may impose restrictions on the Bank's ability to pay dividends as a condition to the Bank's participation in any stabilization program. In the event the Bank is unable to pay dividends to us, it is likely that we, in turn, would have to stop paying dividends on our common stock. Our failure to pay dividends on our common stock could have a material adverse effect on the market price of our common stock. See "Item 1. Business—Supervision and Regulation" above for additional information on the regulatory restrictions to which we and the Bank are subject.

Only a limited trading market exists for our common stock which could lead to price volatility.

        Our common stock trades on The NASDAQ Global Select Stock Market under the symbol "PACW" and our trading volume is modest. The limited trading market for our common stock may cause fluctuations in the market value of our common stock to be exaggerated, leading to price volatility in excess of that which would occur in a more active trading market of our common stock. In addition, even if a more active market in our common stock develops, we cannot assure you that such a market will continue or that stockholders will be able to sell their shares.

Our allowance for credit losses may not be adequate to cover actual losses.

        In accordance with accounting principles generally accepted in the United States, we maintain an allowance for loan losses to provide for loan defaults and non-performance and a reserve for unfunded loan commitments which, when combined, we refer to as the allowance for credit losses. Our allowance for credit losses may not be adequate to address actual credit losses, and future provisions for credit losses could materially and adversely affect our operating results. Our allowance for credit losses is based on prior experience and an evaluation of the risks in the current portfolio. The amount of future losses is susceptible to changes in economic, operating and other conditions, including changes in interest rates that may be beyond our control, and these losses may exceed current estimates. Our federal and state regulators, as an integral part of their examination process, review our loans and allowance for credit losses. While we believe our allowance for credit losses is appropriate for the risk identified in the Company's loan portfolio, we cannot assure you that we will not further increase the

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allowance for credit losses, that it will be sufficient to address losses, or that regulators will not require us to increase this allowance. Any of these occurrences could materially and adversely affect our earnings. See "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations" of this Annual Report on Form 10-K for more information.

Our acquisitions may subject us to unknown risks.

        We have completed 22 acquisitions since May 2000, including the FDIC-assisted acquisitions of Los Padres Bank in August 2010 and Affinity Bank in August 2009. Certain events may arise after the date of an acquisition, or we may learn of certain facts, events or circumstances after the closing of an acquisition, that may affect our financial condition or performance or subject us to risk of loss. These events include, but are not limited to: litigation resulting from circumstances occurring at the acquired entity prior to the date of acquisition; loan downgrades and credit loss provisions resulting from underwriting of certain acquired loans determined not to meet our credit standards; personnel changes that cause instability within a department; delays in implementing new policies or procedures or the failure to apply new policies or procedures; and other events relating to the performance of our business. Acquisitions involve inherent uncertainty and we cannot determine all potential events, facts and circumstances that could result in loss or give assurances that our investigation or mitigation efforts will be sufficient to protect against any such loss.

We are dependent on key personnel and the loss of one or more of those key personnel may materially and adversely affect our prospects.

        We currently depend heavily on the services of our chairman, John Eggemeyer, our chief executive officer, Matthew Wagner, and a number of other key management personnel. The loss of Mr. Eggemeyer's or Mr. Wagner's services or that of other key personnel could materially and adversely affect our results of operations and financial condition. Our success also depends, in part, on our ability to attract and retain additional qualified management personnel. Competition for such personnel is strong in the banking industry, and we may not be successful in attracting or retaining the personnel we require.

Concentrated ownership of our common stock creates a risk of sudden changes in our share price.

        As of March 4, 2011, directors and members of our executive management team owned or controlled approximately 3.7% of our common stock, excluding shares that may be issued to executive officers upon vesting of restricted stock awards. Investors who purchase our common stock may be subject to certain risks due to the concentrated ownership of our common stock. The sale by any of our large stockholders of a significant portion of that stockholder's holdings could have a material adverse effect on the market price of our common stock. In addition, the registration of any significant amount of additional shares of our common stock will have the immediate effect of increasing the public float of our common stock and any such increase may cause the market price of our common stock to decline or fluctuate significantly.

Our largest stockholder is a registered bank holding company, and the activities and regulation of such stockholder may materially and adversely affect the permissible activities of the Company.

        CapGen Capital Group II LP, which we refer to as CapGen, beneficially owned approximately 10.9% of the Company as of March 4, 2011. CapGen is a registered bank holding company under the BHCA and is regulated by the FRB. Under FRB guidelines, bank holding companies must be a "source of strength" for their subsidiaries. See "Item 1. Business—Supervision and Regulation—Bank Holding Company Regulation" above for more information. Regulation of CapGen by the FRB may materially and adversely affect the activities and strategic plans of the Company should the FRB determine that CapGen or any other company in which either has invested has engaged in any unsafe

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or unsound banking practices or activities. While we have no reason to believe that the FRB is proposing to take any action with respect to CapGen that would adversely affect the Company, we remain subject to such risk.

A natural disaster could harm the Company's business.

        Historically, California, in which a substantial portion of the Company's business is located, has been susceptible to natural disasters, such as earthquakes, floods and wild fires. The nature and level of natural disasters cannot be predicted and may be exacerbated by global climate change. These natural disasters could harm the Company's operations through interference with communications, including the interruption or loss of the Company's computer systems, which could prevent or impede the Company from gathering deposits, originating loans and processing and controlling its flow of business, as well as through the destruction of facilities and the Company's operational, financial and management information systems. Additionally, natural disasters could negatively impact the values of collateral securing the Company's loans and interrupt our borrowers' abilities to conduct their business in a manner to support their debt obligations, either of which could result in losses and increased provisions for credit losses.

Our decisions regarding the fair value of assets acquired, including the FDIC loss sharing asset, could be inaccurate which could materially and adversely affect our business, financial condition, results of operations, and future prospects.

        Management makes various assumptions and judgments about the collectibility of the acquired loans, including the creditworthiness of borrowers and the value of the real estate and other assets serving as collateral for the repayment of secured loans. In FDIC-assisted acquisitions that include loss sharing agreements, we may record a loss sharing asset that we consider adequate to absorb future losses which may occur in the acquired loan portfolio. In determining the size of the loss sharing asset, we analyze the loan portfolio based on historical loss experience, volume and classification of loans, volume and trends in delinquencies and nonaccruals, local economic conditions, and other pertinent information. If our assumptions are incorrect, the balance of the FDIC loss sharing asset may at any time be insufficient to cover future loan losses, and credit loss provisions may be needed to respond to different economic conditions or adverse developments in the acquired loan portfolio. Any increase in future losses on loan and other assets covered by loss sharing agreements could have a negative effect on our operating results.

Our ability to obtain reimbursement under the loss sharing agreements on covered assets depends on our compliance with the terms of the loss sharing agreements.

        Management must certify to the FDIC on a quarterly basis our compliance with the terms of the FDIC loss sharing agreements as a prerequisite to obtaining reimbursement from the FDIC for realized losses on covered assets. The required terms of the agreements are extensive and failure to comply with any of the guidelines could result in a specific asset or group of assets temporarily or permanently losing their loss sharing coverage. Additionally, management may decide to forgo loss share coverage on certain assets to allow greater flexibility over the management of certain assets. As of December 31, 2010, $1.0 billion, or 18.4%, of the Company's assets were covered by the FDIC loss sharing agreements.

        Under the terms of the FDIC loss sharing agreements, the assignment or transfer of the loss sharing agreement to another entity generally requires the written consent of the FDIC. Based on the manner in which assignment is defined in the agreements, each of the following requires the prior written consent of the FDIC:

1.

a merger or consolidation of the Bank with and into another financial institution;

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2.

the sale of all or substantially all of the Bank's assets to another financial institution; and



3.

with respect to covered assets acquired in the Affinity acquisition, for a period of 36 months after the August 28, 2009 acquisition date



a.

the sale by any individual shareholder, or shareholders acting in concert, of more than 9% of the outstanding shares of either the Bank or the Company;



b.

the sale of shares by the Bank or the Company in a public or private offering that increases the number of shares outstanding of either the Bank or the Company by more than 9%.

        No assurances can be given that we will manage the covered assets in such a way as to always maintain loss share coverage on all such assets.

ITEM 1B.    UNRESOLVED STAFF COMMENTS

        None.

ITEM 2.    PROPERTIES

        As of March 1, 2011, we had a total of 95 properties consisting of 77 operating branch offices, 1 annex office, 3 operations centers, 8 loan offices, and 6 other properties of which 2 are subleased. We own 8 locations and the remaining properties are leased. Almost all properties are located in Southern California. Pacific Western's principal office is located at 10250 Constellation Blvd., Suite 1640, Los Angeles, CA 90067.

        For additional information regarding properties of the Company and Pacific Western, see Note 9 of Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data."

ITEM 3.    LEGAL PROCEEDINGS

        In the ordinary course of our business, we are party to various legal actions, which we believe are incidental to the operation of our business. The outcome of such legal actions and the timing of ultimate resolution are inherently difficult to predict. Because of these factors, the Company cannot provide a meaningful estimate of the range of reasonably possible outcomes of claims in the aggregate or by individual claim. In the opinion of management, based upon information currently available to us, any resulting liability is not likely to have a material adverse effect on the Company's consolidated financial position, results of operations or cash flows.

ITEM 4.    RESERVED

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PART II

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

Marketplace Designation, Sales Price Information and Holders

        Our common stock is listed on The Nasdaq Global Select Market and is traded under the symbol "PACW." The following table summarizes the high and low sale prices for each quarterly period ended since January 1, 2009 for our common stock, as quoted and reported by The Nasdaq Stock Market, or Nasdaq:

        As of March 2, 2011, the closing price of our common stock on Nasdaq was $20.20 per share. As of that date, based on the records of our transfer agent, there were approximately 2,001 record holders of our common stock.

Dividends

        Our ability to pay dividends to our stockholders is subject to the restrictions set forth in the Delaware General Corporation Law, or the DGCL. The DGCL provides that a corporation, unless otherwise restricted by its certificate of incorporation, may declare and pay dividends out of its surplus or, if there is no surplus, out of net profits for the fiscal year in which the dividend is declared and/or for the preceding fiscal year, as long as the amount of capital of the corporation is not less than the aggregate amount of the capital represented by the issued and outstanding stock of all classes having a preference upon the distribution of assets. Surplus is defined as the excess of a corporation's net assets (i.e., its total assets minus its total liabilities) over the capital associated with issuances of its common stock. Moreover, DGCL permits a board of directors to reduce its capital and transfer such amount to its surplus. In determining the amount of surplus of a Delaware corporation, the assets of the corporation, including stock of subsidiaries owned by the corporation, must be valued at their fair market value as determined by the board of directors, regardless of their historical book value. Our ability to pay dividends is also subject to certain other limitations. See "Item 1. Business—Supervision and Regulation" in Part I of this Annual Report on Form 10-K and Note 19 of the Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data."

        Set forth in the table above are the dividends declared and paid by the Company during the two most recent fiscal years. Our ability to pay cash dividends to our stockholders is also limited by certain covenants contained in the indentures governing trust preferred securities issued by us or entities that we have acquired, and the debentures underlying the trust preferred securities. Generally the

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indentures provide that if an Event of Default (as defined in the indentures) has occurred and is continuing, or if we are in default with respect to any obligations under our guarantee agreement which covers payments of the obligations on the trust preferred securities, or if we give notice of any intention to defer payments of interest on the debentures underlying the trust preferred securities, then we may not, among other restrictions, declare or pay any dividends (other than a dividend payable by the Bank to the holding company) with respect to our common stock. Notification to the FRB is also required prior to our declaring and paying a cash dividend to our stockholders during any period in which our quarterly net earnings are insufficient to fund the dividend amount. Under such circumstances, we may not pay a dividend should the FRB object until such time as we receive approval from the FRB or no longer need to provide notice under applicable regulations.

        Holders of Company common stock are entitled to receive dividends declared by the Board of Directors out of funds legally available under state law governing the Company and certain federal laws and regulations governing the banking and financial services business. During 2010, 2009, and 2008, the Company paid $1.4 million, $11.1 million, and $35.4 million, respectively, in cash dividends on common stock.

        We can provide no assurance that we will continue to declare dividends on a quarterly basis or otherwise. The declaration of dividends by the Company is subject to the discretion of our Board of Directors. Our Board of Directors will take into account such matters as general business conditions, our financial results, projected cash flows, capital requirements, contractual, legal and regulatory restrictions on the payment of dividends by us to our stockholders or by our subsidiary to the holding company, and such other factors as our Board of Directors may deem relevant.

        PacWest's primary source of income is the receipt of cash dividends from the Bank. The availability of cash dividends from the Bank is limited by various statutes and regulations. It is possible, depending upon the financial condition of the bank in question, and other factors, that the FRB, the FDIC or the DFI could assert that payment of dividends or other payments is an unsafe or unsound practice. Pacific Western is subject to restrictions under certain federal and state laws and regulations governing banks which limit its ability to transfer funds to the holding company through intercompany loans, advances or cash dividends.

        Dividends paid by state banks, such as Pacific Western, are regulated by the DFI under its general supervisory authority as it relates to a bank's capital requirements. A state bank may declare a dividend without the approval of the DFI as long as the total dividends declared in a calendar year do not exceed either the retained earnings or the total of net earnings for three previous fiscal years less any dividend paid during such period. During 2010, no dividends were paid to PacWest from the Bank. As of this date and for the foreseeable future, any further cash dividends from the Bank to the Company will require DFI approval. See "Item 1. Business—Supervision and Regulation," in Part I of this Annual Report on Form 10-K for further discussion of potential regulatory limitations on the holding company's receipt of funds from the Bank, as well as "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations—Liquidity" and Note 19 of the Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data" for a discussion of other factors affecting the availability of dividends and limitations on the ability to declare dividends.

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Securities Authorized for Issuance Under Equity Compensation Plans

        The following table provides information as of December 31, 2010, regarding securities issued and to be issued under our equity compensation plans that were in effect during fiscal 2010:

Recent Sales of Unregistered Securities and Use of Proceeds

        None.

Repurchases of Common Stock

        In January 2009, all participants in the Company's Directors Deferred Compensation Plan, or the DDCP, received distributions of amounts previously deferred and the DDCP was terminated. Upon termination of the DDCP 184,395 common shares were distributed to the participants.

        Prior to 2009, participants in the DDCP were able to invest deferred amounts in the Company's common stock. The Company had the discretion whether to track purchases of common stock as if made, or to fully fund the DDCP via purchases of stock with deferred amounts. Purchases of Company common stock by the rabbi trust of the DDCP were considered repurchases of common stock by the Company since the rabbi trust was an asset of the Company. Actual purchases of Company common stock via the DDCP were made through open market purchases pursuant to the terms of the DDCP, which include a predetermined formula and schedule for the purchase of such stock in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934. Pursuant to the terms of the DDCP, generally purchases were actually made or deemed to be made in the open market on the 15th of the month (or the next trading day) following the day on which deferred amounts were contributed to the DDCP, beginning March 15 of each year.

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        The following table presents stock purchases made during the fourth quarter of 2010:

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Five-Year Stock Performance Graph

        The following chart compares the yearly percentage change in the cumulative shareholder return on our common stock based on the closing price during the five years ended December 31, 2010, with (1) the Total Return Index for U.S. companies traded on The Nasdaq Stock Market (the "NASDAQ Composite"), (2) the Total Return Index for NASDAQ Bank Stocks (the "NASDAQ Bank Index") and (3) the Total Return Index for the KBW Regional Bank Stocks (the "KBW Regional Banking Index"). This comparison assumes $100 was invested on December 31, 2005, in our common stock and the comparison groups and assumes the reinvestment of all cash dividends prior to any tax effect and retention of all stock dividends. PacWest's total cumulative loss was 55.6% over the five year period ending December 31, 2010 compared to a gain of 25.9% and losses of 24.7% and 44.0% for the NASDAQ Composite, NASDAQ Bank Index, and KBW Regional Banking Index, respectively.

COMPARISON OF 5 YEAR CUMULATIVE TOTAL RETURN*
Among PacWest Bancorp, the NASDAQ Composite Index,
the NASDAQ Bank Index and the KBW Regional Banking Index

*

$100 invested on December 31, 2005 in stock or index, including reinvestment of dividends.

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ITEM 6.    SELECTED FINANCIAL DATA

        The following table sets forth certain of our financial and statistical information for each of the years in the five-year period ended December 31, 2010. This data should be read in conjunction with our audited consolidated financial statements as of December 31, 2010 and 2009, and for each of the years in the three-year period ended December 31, 2010 and related Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data."

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^(a)

Operating results of acquired companies are included from the respective acquisition dates. See Note 3 of the Notes to Consolidated Financial Statements contained in "Item 8. Financial Statements and Supplementary Data."

^(b)

Includes 1,230,582 shares, 1,095,417 shares, 1,309,586 shares, 861,269 shares, and 750,014 shares of unvested restricted stock outstanding at December 31, 2010, 2009, 2008, 2007, and 2006, respectively.

^(c)

During 2010, the Bank executed two sales of non-covered adversely classified loans totaling $398.5 million that included a total of $128.1 million in nonaccrual loans. For further information about the 2010 loan sales and non-covered loan portfolio concentrations as of December 31, 2010, see "—Overview—Non-Covered Classified Loan Sales" included in "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations."

^(d)

The 2009 efficiency ratio includes the gain from the Affinity acquisition. Excluding this gain, the efficiency ratio would be 70.29%. The 2008 efficiency ratio excludes the goodwill write-off. Including the goodwill write-off, the efficiency ratio would be 371.65%.

^(e)

Not meaningful.

(1)

Includes two loans to one borrower with a balance of $13.9 million