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SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

FOR ANNUAL AND TRANSITION REPORTS PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

(Mark one)

For the fiscal year ended December 31, 2003

For the transition period from                      to                     .

Commission File No. 0-25034

GREATER BAY BANCORP

(Exact name of registrant as specified in its charter)

2860 West Bayshore Road, Palo Alto, California 94303

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (650) 813-8200

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

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

Common Stock, no par value

Guarantee of Greater Bay Bancorp with respect to the

9.00% Cumulative Trust Preferred Securities of GBB Capital V

Preferred Share Purchase Rights

(Title of classes)

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

Indicate by check mark 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 the registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ¨

Indicate by check mark whether the registrant is an accelerated filer (as defined in Exchange Act Rule 12b-2). Yes  x  No  ¨

The aggregate market value of the Common Stock held by non-affiliates, based upon the closing sale price of the Common Stock on June 30, 2003, as reported on the Nasdaq National Market System, was approximately $916,562,000. Shares of Common Stock held by each officer, director and holder of 5% or more of the outstanding Common Stock have been excluded in that such persons may be deemed to be affiliates. Such determination of affiliate status is not necessarily a conclusive determination for other purposes. Registrant has no non-voting common stock.

As of February 13, 2004, 52,884,771 shares of the Registrant’s Common Stock were outstanding.

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GREATER BAY BANCORP

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ANNUAL REPORT ON FORM 10-K

PART I

Discussions of certain matters contained in this Annual Report on Form 10-K may constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”), and as such, may involve risks and uncertainties. These forward-looking statements relate to, among other things, expectations of the business environment in which Greater Bay Bancorp and its subsidiaries operates, projections of future performance, perceived opportunities in the market and statements regarding our mission and vision. Our actual results, performance and achievements may differ materially from the results, performance and achievements expressed or implied in such forward-looking statements. For a discussion of some of the factors that might cause such a difference, see “ITEM 1. BUSINESS—Factors That May Affect Future Results of Operations.”

Greater Bay Bancorp

Greater Bay Bancorp (“Greater Bay”, on a parent-only basis, and “we” or “our”, on a consolidated basis) is a financial holding company with one bank subsidiary, Greater Bay Bank, National Association (the “Bank”), and one commercial insurance brokerage subsidiary, ABD Insurance and Financial Services (“ABD”). The Bank conducts business through the following operating divisions: Bank of Petaluma, Bank of Santa Clara, Bay Area Bank, Bay Bank of Commerce, Coast Commercial Bank, Cupertino National Bank, Golden Gate Bank, Mid-Peninsula Bank, Mt. Diablo National Bank, Peninsula Bank of Commerce, San Jose National Bank, CAPCO, Greater Bay Bank Contra Costa Region, Greater Bay Bank Fremont Region, Greater Bay Bank Carmel, Greater Bay Bank Marin, Greater Bay Bank SBA Lending Group, Greater Bay Capital, Greater Bay Corporate Finance Group (“Corporate Finance”), Greater Bay International Banking Division, Greater Bay Trust Company, The Matsco Companies (“Matsco”), Pacific Business Funding and the Venture Banking Group.

On February 1, 2004, we completed the merger of ten bank subsidiaries into the Bank, formerly Mid-Peninsula Bank. Our individual business units will retain their names in the communities they serve. We also merged MPB Investment Trust (“MPBIT”) and SJNB Investment Trust (“SJNBIT”) into CNB Investment Trust I (“CNBIT I”) which is a subsidiary of the Bank. This entity, along with its subsidiary CNB Investment Trust II (“CNBIT II”), (collectively, the “REITs”) was formed in order to provide flexibility in raising capital.

We provide a wide range of commercial banking and financial services to small and medium-sized businesses, property managers, business executives, real estate developers, professionals and other individuals. We operate community banking offices throughout the San Francisco Bay Area including the Silicon Valley, San Francisco and the San Francisco Peninsula, the East Bay, Santa Cruz, Marin, Monterey and Sonoma Counties. ABD provides commercial insurance brokerage, employee benefits consulting and risk management solutions to business clients throughout the United States. We also own a broker-dealer, which executes mutual fund transactions on behalf of our clients’ employee benefit plans. CAPCO’s office is located in Bellevue, Washington and it operates in the Pacific Northwest. Greater Bay Capital finances equipment leases and is located in Chicago, Illinois. Matsco markets its dental and veterinarian financing services nationally.

At December 31, 2003, we had total assets of $7.6 billion, total loans, net, of $4.4 billion and total deposits of $5.3 billion.

History

Greater Bay Bancorp was formed as the result of the November 1996 merger of Cupertino National Bancorp and Mid-Peninsula Bancorp. On consummation of the November 1996 merger between Cupertino National Bancorp and Mid-Peninsula Bancorp, Mid-Peninsula Bancorp changed its name to Greater Bay Bancorp and Cupertino National Bank and Mid-Peninsula Bank became wholly owned subsidiaries.

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Greater Bay has continued to expand its presence within its market areas by affiliating with other quality banking organizations and select niche financial services companies. In addition, we have been successful in opening key regional bank locations to respond to market and client demands, while also selectively opening key new businesses that expand our product offerings.

The following provides a chronological listing of significant mergers and acquisitions that we have completed since November 27, 1996:

The acquisitions of The Matsco Companies, Inc., CAPCO, ABD and Sullivan & Curtis Insurance Brokers of Washington, LLC (“S&C”) were accounted for using the purchase accounting method. All of the other acquisitions were accounted for as a pooling-of-interests and, accordingly, all of our financial information for the periods prior to the acquisitions has been restated as if these acquisitions had occurred at the beginning of the earliest reporting period presented.

Our Goals

We strive toward six primary goals. These goals are:

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Regional Community Banking Philosophy

In order to meet the demands of the increasingly competitive banking and financial services industries, we operate under a “Regional Community Banking Philosophy.” Our Regional Community Banking Philosophy is based on our belief that banking clients value doing business with locally managed banking offices that can provide a full service commercial banking relationship through an understanding of the clients’ financial needs and the flexibility to deliver customized solutions through our menu of products and services. We also believe that banks which becomes part of Greater Bay Bancorp and implement our Regional Community Banking Philosophy are better able to build successful client relationships from having local autonomy and flexibility in serving client needs, while receiving cost effective centralized administrative support services.

Our community banking offices, through our relationship managers, have established strong reputations and client followings in their market areas through attention to client service and an understanding of client needs. The primary focus for our relationship managers is to cultivate and nurture their client relationships. Relationship managers are assigned to each borrowing client to provide continuity in the relationship. This emphasis on personalized relationships requires that all of the relationship managers maintain close ties to the communities in which they serve, so they are able to capitalize on their efforts through expanded business opportunities.

While client service decisions and day-to-day operations are managed locally, the banking offices benefit from a centralized source of specialized client services, such as business cash management, international trade finance services and business insurance products. In addition, the banking offices benefit from centralized administrative functions, including support in credit policy formulation and review, investment management, data processing, accounting, loan servicing and other specialized support functions. All of these centralized services are designed to enhance the ability of the relationship managers to expand their client relationship base.

Corporate Growth Strategy

Our primary objective is to become preeminent independent financial services company by focusing on increasing our market share within the communities we serve through continued internal growth and strategic acquisitions.

Greater Bay Bancorp’s Family of Companies

We are organized along business segments, namely: community banking, specialty finance, trust services and insurance brokerage services. We have aggregated 18 operating divisions into the community banking business segment. We have aggregated five operating divisions into the specialty finance business segment. Our trust services business segment consists of a single operating division, Greater Bay Trust Company. Our insurance brokerage services business segment consists of a single operating division, ABD, our insurance brokerage subsidiary. The services that our business segments provide are described further below.

Community Banking

We provide a wide range of commercial banking and financial services to small and medium-sized businesses, real estate developers and property managers, business executives, professionals and other individuals.

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The Bank engages in the full complement of lending activities, including commercial, real estate and consumer loans. The Bank provides commercial loans for working capital and business expansion to small and medium-sized businesses with annual revenues generally in the range of $1.0 million to $100.0 million. We also offer international letters of credit and trade financing.

The Bank offers a wide range of deposit products, including personal and business checking and savings accounts, time deposits and individual retirement accounts. The Bank also offers a wide range of specialized services designed to attract and service the needs of clients and include cash management and international trade finance services for business clients, traveler’s checks, safe deposit and MasterCard and Visa merchant deposit services.

Specialty Finance

We provide an array of specialty finance products including loans to smaller businesses on which the Small Business Administration (“SBA”) generally provides guarantees, asset-based lending and accounts receivable factoring, loans and lease products tailored to the dental and veterinary health professions and capital lease equipment financing.

Trust Services

Through the Greater Bay Trust Company, a division of the Bank, we provide trust services to support the trust needs of the Bank’s business and private banking clients. These services include, but are not limited to, custodial, investment management, estate planning resources and employee benefit plan services.

Insurance Brokerage Services

ABD is a commercial insurance brokerage and employee benefits consulting firm with offices located in California, Washington and Nevada, and clients throughout the United States. ABD is engaged in selling commercial, personal property, casualty, employee benefits, life and retirement insurance products and providing consulting services to consumers of those products, enabling their clients to strengthen their risk management programs. At December 31, 2003, ABD had over $1.7 billion of insurance premiums serviced and $117.5 million in gross revenues for the year ended December 31, 2003.

Market Area

The Bank concentrates on marketing its services to small and medium-sized businesses, professionals and individuals in Alameda, Contra Costa, Marin, Monterey, Santa Clara, San Francisco, San Mateo, Santa Cruz, and Sonoma Counties. The following provides certain economic and demographic data for our market area.

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The commercial base of Alameda, Contra Costa, Marin, Monterey, Santa Clara, Santa Cruz, San Francisco, San Mateo and Sonoma Counties is diverse and includes computer and semiconductor manufacturing, professional services, biotechnology, printing and publishing, aerospace, defense and real estate construction, as well as wholesale and retail trade. As a result of our geographic concentration, our results depend largely upon economic conditions in these areas, which exhibited continuing weakness in 2003. No assurance can be given that significant improvement in the economy will occur in 2004. A prolonged economic downturn could have a material adverse impact on the quality of our loan portfolio and the demand for our products and services and, accordingly, on our results of operations. See “Item 1. Business—Factors That May Affect Future Results of Operations.”

We market our dental and veterinarian financing services nationally through our Matsco division. At December 31, 2003, approximately $567.7 million of Matsco’s outstanding loans and leases were with borrowers located outside of California. Those loans and leases are distributed throughout the United States, with the largest volume originating in Florida, where Matsco has outstanding loans and leases totaling approximately $48.9 million. Our asset based lending services are marketed through our offices in California and Bellevue, Washington, which covers the Pacific Northwest.

ABD provides commercial insurance brokerage, employee benefits consulting and risk management solutions to business clients throughout the United States.

Lending Activities

Underwriting and Credit Administration

The Bank’s lending activities are guided by Board approved lending policies which are recommended by our Credit Policy Committee. Each loan must meet minimum underwriting criteria established in the Bank’s lending policy. Loan requests are approved on a pooled-authority basis up to a maximum limit. Loan requests exceeding these limits are submitted to our Officers’ Loan Committee. Loan requests which exceed the limits of our Officers’ Loan Committee are submitted to the Directors’ Loan Committee. Each of these committees meets on a regular basis in order to provide timely responses to our clients.

Greater Bay employs an outside firm to perform a loan review of the Bank two to three times per year. In addition, our Directors’ Loan Committee, Credit Risk Management Committee, Chief Financial Officer and Executive Vice President, Finance and Accounting review information at least once a month related to delinquencies, nonperforming assets, classified assets and other pertinent information to evaluate credit risk within the Bank’s loan portfolio and to review our allowance for loan and lease losses. Additionally, our Credit Policy Committee and Audit Committee reviews nonperforming assets and our allowance for loan and lease losses quarterly.

Loan Portfolio

The composition of our gross loan portfolio at December 31, 2003 was as follows:

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The interest rates the Bank charges vary with the degree of risk, size and maturity of the loans. In addition, competition from other financial services companies and analyses of the client’s deposit relationship with the Bank and the Bank’s cost of funds impact the interest rate charged on loans.

Commercial Loans.    The Bank provides personalized financial services to the diverse commercial and professional businesses in its market areas. Commercial loans consist primarily of short-term loans (normally with a maturity of up to one year) to support business operations. The Bank focuses on businesses with annual revenues generally between $1.0 million and $100.0 million with borrowing needs generally between $2.0 million and $10.0 million. The Bank’s commercial clients are drawn from a wide variety of manufacturing, technology, real estate, wholesale and service businesses.

Commercial loans typically include revolving lines of credit collateralized by accounts receivable, inventory and equipment. In underwriting commercial loans, we emphasize the borrower’s earnings history, cash flow, capitalization, leverage and sources of repayment. In some instances, we require third party guarantees or highly liquid collateral (such as time deposits and investment securities). Commercial loan pricing is generally at a rate tied to the prime rate, as quoted in the Wall Street Journal, or the Bank’s reference rates.

The Venture Banking Group provides innovative lending products and other financial services, tailored to the needs of start-up and development-stage companies. The Venture Banking Group’s typical clients include venture capital and technology companies, ranging from multimedia, software and telecommunications providers to biotechnology and medical device firms. Borrowings are generally secured by minimum cash balances, accounts receivable, intellectual property rights, inventory and equipment of the companies. The financial strength of these companies also tends to be bolstered by the presence of venture capital investors among their shareholders. Because many of these technology companies are in the start-up or development phase, they may not generate any revenues for several years. We often receive warrants from these companies as part of the compensation for our services.

We participate as a preferred lender in many SBA programs through the Greater Bay Bank SBA Lending Group. As a preferred lender, we have authority to authorize, on behalf of the SBA, the SBA guaranty on loans under the 7A program. This can represent a substantial savings to the customer as this status results in more rapid turnaround of loan applications submitted to the SBA for approval. The SBA Lending Group utilizes both the 504 program, which is focused toward longer-term financing of buildings and other long-term assets, and the 7A program, which is primarily used for financing of the equipment, inventory and working capital needs of eligible businesses generally over a three-to-seven-year term. The collateral position in the SBA loans is enhanced by the SBA guaranty in the case of 7A loans, and by lower loan-to-value ratios under the 504 program. We have the ability to sell the guaranteed portion of these loans to investors and retain the unguaranteed portion and servicing rights in our own portfolio. Funding for the SBA programs depend on annual appropriations by the U.S. Congress.

We offer a complete range of financial products and services through our Matsco division to meet the needs of dentists and veterinarians throughout their professional careers. Matsco’s principal financial products include practice start-up financing, practice expansion financing, practice acquisition financing, working capital and financing for retirement planning. These products are structured as either equipment leases or loans. We also offer capital equipment lease financing through our Greater Bay Capital division.

We offer asset-based lending and accounts receivable factoring products through our Pacific Business Funding and CAPCO divisions that provide alternative funding and support programs designed to enhance our small business banking services.

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Commercial Real Estate Term Loans.    The Bank provides medium-term commercial real estate loans secured by commercial or industrial buildings where the owner either uses the property for business purposes or derives income from tenants. Our loan policies require the principal balance of the loan, generally between $400,000 and $15.0 million, to be no more than 70% of the lower of actual or stabilized appraised value of the underlying real estate collateral at the inception of the loan. The loans, which are typically secured by first deeds of trust only, generally have terms of no more than seven to ten years and are amortized over 20-25 years. Most of these loans have rates tied to the prime rate, with many adjusting whenever the prime rate changes; the remaining loans adjust every two or three years depending on the term of the loan.

Real Estate Construction and Land Loans.    The Bank’s real estate construction loan activity primarily focuses on providing short-term (generally less than one year maturity) loans to individuals and developers with whom the Bank has established relationships for the construction of residential property in the Bank’s market areas. Real estate construction loans for single family residences typically range between approximately $500,000 and $1.0 million, and for multi-unit projects typically ranging between approximately $1.5 million and $5.0 million.

Residential real estate construction loans are typically secured by first deeds of trust and require guarantees of the borrower. The economic viability of the project and the borrower’s creditworthiness are primary considerations in the loan underwriting decision. Generally, these loans provide an attractive yield, but may carry a higher than normal risk of loss or delinquency, particularly if general real estate values decline. The Bank utilizes approved independent local appraisers. Loan-to-value ratios generally do not exceed 65% to 75% of the appraised value of the property. The Bank monitors projects during the construction phase through regular construction inspections and a disbursement program tied to the percentage of completion of each project.

The Bank also occasionally makes land loans to borrowers who intend to construct a single family residence on the lot generally within 12 months. In addition, the Bank makes commercial real estate construction loans to high net worth clients with adequate liquidity. Such loans are typically secured by first deeds of trust and require guarantees of the borrower.

Other Real Estate Loans.    Other real estate loans include equity lines of credit secured primarily by second deeds of trust on single-family residences. Most of these loans bear interest rates based on the prime rate and have terms of no more than 10 years. The other significant component included in other real estate is comprised of SBA loans participated under the 7A program. Such loans may be revolving and have maturities up to one year, or they may be amortizing over terms up to 25 years. In most cases, 7A loans are secured by both business assets and deeds of trust.

Consumer and Other Loans.    The Bank’s consumer and other loan portfolio is divided between installment loans secured by automobiles and aircraft, home improvement loans and lines of credit which are often secured by residential real estate. Installment loans tend to be fixed rate and longer-term (one-to-five year maturity), while the equity lines of credit and home improvement loans are generally at a floating rate and are reviewed for renewal on an annual basis. The Bank also has a minimal portfolio of credit card loans, issued as an additional service to our clients.

We also provide a wide range of financial services to support the international banking needs of the Bank’s clients, including identifying certain risks of conducting business abroad and providing international letters of credit, documentary collections and other trade finance services. In 2001, the Export-Import Bank of the United States increased our International Banking Division’s delegated authority status from the “Medium” level to the “High” level to provide foreign receivable financing to local exporters. The Export-Import Bank allows “High” level delegated authority lenders to approve working capital loans up to $5.0 million per exporter, and to approve an aggregate total of up to $75.0 million in loans.

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Deposits

The Bank obtains deposits primarily from small and medium-sized businesses, business executives, professionals and other individuals. The Bank offers the usual and customary range of depository products that commercial banks provide to customers. The Bank’s deposits are not received from a single depositor or group of affiliated depositors, the loss of any one of which would have a material adverse effect on our business. Rates paid on deposits vary among the categories of deposits due to different terms, the size of the individual deposit, and rates paid by competitors on similar deposits.

Competition

The banking and financial services industry in California generally, and in the Bank’s market areas specifically, is highly competitive. The increasingly competitive environment is a result primarily of changes in regulation, changes in technology and product delivery systems, and the accelerating pace of consolidation among financial services providers. The Bank competes for loans, deposits, and customers with other commercial banks, savings and loan associations, securities and brokerage companies, mortgage companies, insurance companies, finance companies, money market funds, credit unions, and other nonbank financial service providers. Many of these competitors are much larger in total assets and capitalization, have greater access to capital markets and offer a broader range of financial services than the Bank.

In order to compete with other financial services providers, the Bank principally relies upon local promotional activities, personal relationships established by officers, directors, and employees, and specialized services tailored to meet the needs of the communities served. In those instances where the Bank is unable to accommodate a customer’s needs, the Bank may arrange for those services to be provided by its correspondents. The Bank has 45 offices located in Alameda, Contra Costa, Marin, Monterey, San Francisco, San Mateo, Santa Clara, Santa Cruz and Sonoma counties in California.

As of June 30, 2003, the latest date for which the FDIC branch data is available, the Bank’s deposits represented 2.69% of the deposits for all financial service companies in the San Francisco Bay Area, which includes Napa and Solano Counties in addition to the nine counties shown below. At that same date, the Bank’s deposits represented:

Economic Conditions, Government Policies, Legislation, and Regulation

Our profitability, like most financial institutions, is primarily dependent on interest rate differentials. In general, the difference between the interest rates paid by us on interest-bearing liabilities, such as deposits and borrowings, and the interest rates received by us on our interest-earning assets, such as loans extended to our clients and securities held in our securities portfolio, comprises the major portion of our earnings. These rates are highly sensitive to many factors that are beyond our control, such as inflation, recession and unemployment, and the impact which future changes in domestic and foreign economic conditions might have on us cannot be predicted.

Our business is also influenced by the monetary and fiscal policies of the federal government and the policies of regulatory agencies, particularly the Board of Governors of the Federal Reserve System (the “Federal

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Reserve”). The Federal Reserve implements national monetary policies (with objectives such as curbing inflation and combating recession) through its open-market operations in U.S. Government securities by adjusting the required level of reserves for depository institutions subject to its reserve requirements, and by varying the target federal funds and discount rates applicable to borrowings by depository institutions. The actions of the Federal Reserve in these areas influence the growth of bank loans, investments, and deposits and also affect interest rates earned on interest-earning assets and paid on interest-bearing liabilities. The nature and impact on us of any future changes in monetary and fiscal policies cannot be fully predicted.

From time to time, legislation, as well as regulations, are enacted which have the effect of increasing the cost of doing business, limiting or expanding permissible activities, or affecting the competitive balance between banks and other financial services providers. Proposals to change the laws and regulations governing the operations and taxation of banks, bank holding companies, and other financial institutions and financial services providers are frequently made in the U.S. Congress, in the state legislatures, and before various regulatory agencies. This legislation may 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 of this potential legislation will be enacted, and if enacted, the effect that it, or any implementing regulations, would have on our financial condition or results of operations.

In addition, a number of state attorneys general and state bank commissioners have joined in a lawsuit seeking to limit the ability of federal regulators to preempt state law on behalf of federally chartered banks and thrifts such as the Bank. In the event the suit is successful, the Bank could be subject to additional regulation and compliance costs.

Supervision and Regulation

General

Bank holding companies and banks are extensively regulated under both federal and state law. This regulation is intended primarily for the protection of depositors and the deposit insurance fund and not for the benefit of our shareholders. Set forth below is a summary description of the material laws and regulations which relate to our operations. The description is qualified in its entirety by reference to the applicable laws and regulations.

Greater Bay

Greater Bay is a registered financial holding company, and subject to regulation and examination by the Federal Reserve under the Bank Holding Company Act of 1956, as amended (the “BHCA”). Greater Bay is required to file with the Federal Reserve periodic reports and such additional information as the Federal Reserve may require.

The Federal Reserve may require Greater Bay to terminate an activity or terminate control of or liquidate or divest certain subsidiaries, affiliates or investments when the Federal Reserve believes the activity or the control of the subsidiary or affiliate constitutes a significant risk to the financial safety, soundness or stability of any of its banking subsidiaries. The Federal Reserve also has the authority to regulate provisions of certain bank holding company debt, including the authority to impose interest ceilings and reserve requirements on such debt. Under certain circumstances, Greater Bay must file written notice and obtain Federal Reserve approval prior to purchasing or redeeming its equity securities.

Further, Greater Bay is required by the Federal Reserve to maintain certain levels of capital. See “—Capital Standards.”

Greater Bay is required to obtain prior Federal Reserve approval for the acquisition of more than 5% of the outstanding shares of any class of voting securities or substantially all of the assets of any bank or bank holding company. Prior Federal Reserve approval is also required for the merger or consolidation with another bank holding company.

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Greater Bay is prohibited by the BHCA, except in certain statutorily prescribed instances, from acquiring direct or indirect ownership or control of more than 5% of the outstanding voting shares of any company that is not a bank or bank holding company and from engaging directly or indirectly in activities other than those of banking, managing or controlling banks, or furnishing services to its subsidiaries. However, subject to prior Federal Reserve approval, Greater Bay may engage in any, or acquire shares of companies engaged in, activities that the Federal Reserve deems to be so closely related to banking or managing or controlling banks as to be a proper incident thereto.

Under Federal Reserve regulations, Greater Bay is required to serve as a source of financial and managerial strength to the Bank and may not conduct operations in an unsafe or unsound manner. In addition, it is the Federal Reserve’s policy that a bank holding company should stand ready to use available resources to provide adequate capital funds to its subsidiary banks during periods of financial stress or adversity and should maintain the financial flexibility and capital-raising capacity to obtain additional resources for assisting its subsidiary banks. A bank holding company’s failure to meet its obligations to serve as a source of strength to its subsidiary banks will generally be considered by the Federal Reserve to be an unsafe and unsound banking practice or a violation of Federal Reserve regulations or both.

Our common stock is registered with the Securities and Exchange Commission (“SEC”) under the Exchange Act. As such, we are subject to the information, proxy solicitation, insider trading, corporate governance, and other requirements and restrictions of the Exchange Act.

Financial Holding Companies

As a financial holding company, Greater Bay may affiliate with securities firms and insurance companies and engage in other activities that are financial in nature or are incidental or complementary to activities that are financial in nature. “Financial in nature” activities include:

In order to become or remain a financial holding company, the Bank must be well capitalized, well managed, and, except in limited circumstances, in satisfactory compliance with the Community Reinvestment Act. Failure to sustain compliance with such requirements or correct any non-compliance within a fixed time period could lead to divestiture of subsidiary banks or require us to conform all of our activities to those permissible for a bank holding company. A bank holding company that is not also a financial holding company can only engage in banking and such other activities determined by the Federal Reserve to be so closely related to banking or managing or controlling banks as to be a proper incident thereto.

Cure Agreement

During regulatory examinations of Greater Bay and its subsidiaries in 2002, the bank regulatory agencies identified weaknesses in our enterprise-wide risk management programs and following completion of these examinations, Greater Bay received on January 3, 2003 a notice from the Federal Reserve Board advising us that as a result of these weaknesses, we did not meet the continuing financial holding company requirements. In

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response to the notice, Greater Bay delivered to the Federal Reserve Board a corrective action plan designed to enhance our enterprise-wide risk management program. Prior to receipt of the notice from the Federal Reserve Board, Greater Bay had already dedicated significant time and resources to addressing these items, and commenced many of the action items contained within the corrective action plan, including the appointment in December 2002 of a Chief Risk Officer to oversee our enterprise-wide Risk Management Group.

On February 17, 2003, Greater Bay entered into a cure agreement with the Federal Reserve Board which incorporated the terms of Greater Bay’s corrective action plan. On June 27, 2003, the Federal Reserve Board notified Greater Bay that we had fully satisfied all of the terms and conditions of the cure agreement. Accordingly, the Federal Reserve Board terminated the cure agreement.

The Bank

As a national banking association, the Bank is subject to primary supervision, examination, and regulation by the Office of the Comptroller of the Currency (the “OCC”). The Bank is also subject to regulations of the Federal Deposit Insurance Corporation (“FDIC”) as administrator of the Bank Insurance Fund (“BIF”) and the Federal Reserve. If, as a result of an examination of our bank, the OCC should determine that the financial condition, capital resources, asset quality, earnings prospects, management, liquidity or other aspects of our operations are unsatisfactory or that the Bank is violating or has violated any law or regulation, various remedies are available to the OCC. Such remedies include the power to enjoin “unsafe or unsound practices,” to require affirmative action to correct any conditions resulting from any violation or practice, to issue an administrative order that can be judicially enforced, to direct an increase in capital, to restrict our growth, to assess civil monetary penalties, and to remove officers and directors. The FDIC has similar enforcement authority, in addition to its authority to terminate our deposit insurance in the absence of action by the OCC and upon a finding that the Bank is operating in an unsafe or unsound condition, is engaging in unsafe or unsound activities, or that our conduct poses a risk to the deposit insurance fund or may prejudice the interest of its depositors.

A national bank may have a financial subsidiary engaged in any activity authorized for national banks directly or certain permissible activities. Generally, a financial subsidiary is permitted to engage in activities that are “financial in nature” or incidental thereto, even though they are not permissible for the national bank itself. The definition of “financial in nature” includes, among other items, underwriting, dealing in or making a market in securities, including, for example, distributing shares of mutual funds. The subsidiary may not, however, engage as principal in underwriting insurance, issue annuities or engage in real estate development or investment or merchant banking.

A national bank seeking to have a financial subsidiary, and each of its depository institution affiliates, must be “well-capitalized,” “well-managed” and in satisfactory compliance with the Community Reinvestment Act. The total assets of all financial subsidiaries may not exceed the lesser of 45% of a bank’s total assets, or $50 billion. A national bank must exclude from its assets and equity all equity investments, including retained earnings, in a financial subsidiary. The assets of the subsidiary may not be consolidated with the bank’s assets. The bank must also have policies and procedures to assess financial subsidiary risk and protect the bank from such risks and potential liabilities. The Bank presently does not have any financial subsidiaries.

The Sarbanes-Oxley Act of 2002

On July 30, 2002, President Bush signed into law the Sarbanes-Oxley Act of 2002. This new legislation addresses accounting oversight and corporate governance matters, including:

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USA Patriot Act of 2001

The USA Patriot Act of 2001 and its implementing regulations significantly expanded the anti-money laundering and financial transparency laws, including:

Merchant Banking Restrictions

While the BHCA generally prohibits bank holding companies from owning more than 5% of the voting stock of non-financial companies, with limited exceptions, financial holding companies are permitted to engage in merchant banking activities. Permissible merchant banking investments are defined as investments that meet two important requirements:

In addition, there are limits on bank funding of portfolio companies controlled by the bank’s parent financial holding company, transactions between the bank and portfolio companies and on cross-marketing activities between banks and portfolio companies owned by the same financial holding company. However, current rules do not prevent a depository institution from marketing the shares of private equity funds controlled by an affiliated financial holding company, and do not apply to situations in which the financial holding company owns less than 5% of the voting shares of the portfolio company.

Furthermore, capital requirements for merchant banking activities and certain other equity investments employ a sliding scale based on each banking organization’s aggregate equity investments in non-financial entities and Tier 1 capital, requiring banks or holding companies to hold regulatory capital equal to:

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The first 15% of investments that banking companies make through small-business investment companies is exempt; however, the sliding scale applies for any such investments over 15%.

Privacy

Federal banking rules limit the ability of banks and other financial institutions to disclose non-public information about consumers to nonaffiliated third parties. Pursuant to these rules, financial institutions must provide:

These privacy provisions affect how consumer information is transmitted through diversified financial companies and conveyed to outside vendors. We have implemented our privacy policies in accordance with the law.

In recent years, a number of states have implemented their own versions of privacy laws. For example, in 2003, California adopted standards that are more restrictive than federal law, allowing bank customers the opportunity to bar financial companies from sharing information with their affiliates.

Interagency Guidance on Response Programs to Protect Against Identity Theft

On August 12, 2003, the Federal bank and thrift regulatory agencies requested public comment on proposed guidance that would require financial institutions to develop programs to respond to incidents of unauthorized access to customer information, including procedures for notifying customers under certain circumstances. The proposed guidance:

Dividends and Other Transfers of Funds

Dividends from the Bank constitute the principal source of income to Greater Bay. Greater Bay is a legal entity separate and distinct from the Bank. The Bank is subject to various statutory and regulatory restrictions on its ability to pay dividends to Greater Bay. Under such restrictions, the amount available for payment of dividends to Greater Bay (assuming the consolidation of all of Greater Bay’s subsidiary banks had taken place immediately prior to such date) totaled $108.1 million at December 31, 2003. In addition, the Bank’s regulators have the authority to prohibit the Bank from paying dividends, depending upon the Bank’s financial condition, if such payment is deemed to constitute an unsafe or unsound practice.

Transactions with Affiliates

The Bank is subject to certain restrictions imposed by federal law on any extensions of credit to, or the issuance of a guarantee or letter of credit on behalf of, any affiliates, the purchase of, or investments in, stock or other securities thereof, the taking of such securities as collateral for loans, and the purchase of assets of any affiliates. Such restrictions prevent any affiliates from borrowing from us unless the loans are secured by

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marketable obligations of designated amounts. Further, such secured loans and investments by us to or in any affiliate are limited, individually, to 10% of our capital and surplus (as defined by federal regulations), and such secured loans and investments are limited, in the aggregate, to 20% of our capital and surplus. Some of the entities included in the definition of an affiliate are parent companies, sister banks, sponsored and advised companies, investment companies whereby the bank or its affiliate serves as investment advisor, and financial subsidiaries of the bank. Additional restrictions on transactions with affiliates may be imposed on us under the prompt corrective action provisions of federal law. See “ITEM 1. BUSINESS—Supervision and Regulation—Prompt Corrective Action and Other Enforcement Mechanisms.”

Loans-to-One Borrower Limitations

With certain limited exceptions, the maximum amount that a national bank may lend to any borrower (including certain related entities of the borrower) at one time may not exceed 15% of the unimpaired capital and surplus of the institution, plus an additional 10% of unimpaired capital and surplus for loans fully secured by readily marketable collateral. At December 31, 2003, the Bank’s loans-to-one-borrower limit (on a pro forma basis as if the mergers of our bank subsidiaries occurred on that date) was $126.6 million based upon the 15% of unimpaired capital and surplus measurement.

Capital Standards

The federal banking agencies have adopted risk-based minimum capital guidelines intended to provide a measure of capital that reflects the degree of risk associated with a banking organization’s operations for both transactions reported on the balance sheet as assets and transactions which are recorded as off-balance sheet items. Under these guidelines, nominal dollar amounts of assets and credit equivalent amounts of off-balance sheet items are multiplied by one of several risk adjustment percentages, which range from 0% for assets with low credit risk to 100% for assets with relatively high credit risk.

The risk-based capital ratio is determined by classifying assets and certain off-balance sheet financial instruments into weighted categories, with higher levels of capital being required for those categories perceived as representing greater risk. Under the capital guidelines, a banking organization’s total capital is divided into tiers. “Core capital” consists of common equity and qualifying noncumulative perpetual preferred stock. “Tier I capital” consists of (1) common equity, (2) qualifying noncumulative perpetual preferred stock, (3) a limited amount of qualifying cumulative perpetual preferred stock and (4) minority interests in the equity accounts of consolidated subsidiaries (including trust preferred securities), less goodwill and certain other intangible assets. The amount of qualifying Tier I capital that may consist of trust preferred securities is limited to 33% or core capital. “Tier II capital” consists of hybrid capital instruments, perpetual debt, mandatory convertible debt securities, a limited amount of subordinated debt, preferred stock that does not qualify as Tier I capital, a limited amount of the allowance for loan and lease losses and a limited amount of unrealized holding gains on equity securities. “Tier III capital” consists of qualifying unsecured subordinated debt. The sum of Tier II and Tier III capital may not exceed the amount of Tier I capital.

The guidelines require a minimum ratio of qualifying total capital to risk-adjusted assets of 8% and a minimum ratio of Tier I capital to risk-adjusted assets of 4%. In addition to the risk-based guidelines, federal banking regulators require banking organizations to maintain a minimum amount of Tier 1 capital to total assets, referred to as the leverage ratio. For a banking organization rated in the highest of the five categories used by regulators to rate banking organizations, the minimum leverage ratio of Tier I capital to total assets must be 3%. In addition to these uniform risk-based capital guidelines and leverage ratios that apply across the industry, the regulators have the discretion to set individual minimum capital requirements for specific institutions at rates significantly above the minimum guidelines and ratios.

Under applicable regulatory guidelines, the Company Obligated Mandatorily Redeemable Preferred Securities of Subsidiary Trusts Holding Solely Junior Subordinated Debentures (“Trust Preferred Securities”)

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issued by our subsidiary capital trusts qualify as Tier I capital up to a maximum of 33% of core capital. Any additional portion of Trust Preferred Securities would qualify as Tier II capital. As of December 31, 2003, those subsidiary trusts have $204.0 million in Trust Preferred Securities outstanding, all of which qualifies as Tier I Capital. (See Note 11 of the NOTES TO CONSOLIDATED FINANCIAL STATEMENTS for further information regarding these securities including potential changes to their capital treatment).

Prompt Corrective Action and Other Enforcement Mechanisms

Federal banking agencies possess broad powers to take corrective and other supervisory action to resolve the problems of insured depository institutions, including but not limited to, those institutions that fall below one or more prescribed minimum capital ratios. Each federal banking agency has promulgated regulations defining the following five categories in which an insured depository institution will be placed, based on its capital ratios: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized, and critically undercapitalized. At December 31, 2003, Greater Bay and all of its subsidiary banks exceeded the required ratios for classification as “well capitalized.”

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. The federal banking agencies, however, may not treat a significantly undercapitalized institution as critically undercapitalized unless its capital ratio actually warrants such treatment.

In addition to measures taken under the prompt corrective action provisions, commercial banking organizations may be subject to potential enforcement actions by the federal regulators for unsafe or unsound practices in conducting their businesses or for violations of any law, rule, regulation, or any condition imposed in writing by the agency or any written agreement with the agency. Finally, pursuant to an interagency agreement, the FDIC can examine any institution that has a substandard regulatory examination score or is considered undercapitalized—without the express permission of the institution’s primary regulator.

Safety and Soundness Standards

The federal banking agencies have adopted guidelines designed to assist the federal banking agencies in identifying and addressing potential safety and soundness concerns before capital becomes impaired. The guidelines set forth operational and managerial standards relating to: (i) internal controls, information systems and internal audit systems, (ii) loan documentation, (iii) credit underwriting, (iv) asset growth, (v) earnings, and (vi) compensation, fees and benefits. In addition, the federal banking agencies have also adopted safety and soundness guidelines with respect to asset quality and earnings standards. These guidelines provide six standards for establishing and maintaining a system to identify problem assets and prevent those assets from deteriorating. Under these standards, an insured depository institution should: (i) conduct periodic asset quality reviews to identify problem assets, (ii) estimate the inherent losses in problem assets and establish reserves that are sufficient to absorb estimated losses, (iii) compare problem asset totals to capital, (iv) take appropriate corrective action to resolve problem assets, (v) consider the size and potential risks of material asset concentrations, and (vi) provide periodic asset quality reports with adequate information for management and the board of directors to assess the level of asset risk. These guidelines also set forth standards for evaluating and monitoring earnings and for ensuring that earnings are sufficient for the maintenance of adequate capital and reserves.

Premiums for Deposit Insurance

Through the BIF, the FDIC insures our customer deposits up to prescribed limits for each depositor. The amount of FDIC assessments paid by each BIF member institution is based on its relative risk of default as

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measured by regulatory capital ratios and other factors. Specifically, the assessment rate is based on the institution’s capitalization risk category and supervisory subgroup category. An institution’s capitalization risk category is based on the FDIC’s determination of whether the institution is well capitalized, adequately capitalized or less than adequately capitalized. An institution’s supervisory subgroup category is based on the FDIC’s assessment of the financial condition of the institution and the probability that FDIC intervention or other corrective action will be required.

FDIC-insured depository institutions pay an assessment rate equal to the rate assessed on deposits insured by the Savings Association Insurance Fund.

The assessment rate currently ranges from zero to 27 cents per $100 of domestic deposits. The FDIC may increase or decrease the assessment rate schedule on a semi-annual basis. Due to continued growth in deposits and some recent bank failures, the BIF is nearing its minimum ratio of 1.25% of insured deposits as mandated by law. If the ratio drops below 1.25%, it is likely the FDIC will be required to assess premiums on all banks. Any increase in assessments or the assessment rate could have a material adverse effect on our earnings, depending on the amount of the increase. Furthermore, the FDIC is authorized to raise insurance premiums under certain circumstances.

The FDIC is authorized to terminate a depository institution’s deposit insurance upon a finding by the FDIC that the institution’s financial condition is unsafe or unsound or that the institution has engaged in unsafe or unsound practices or has violated any applicable rule, regulation, order or condition enacted or imposed by the institution’s regulatory agency. The termination of deposit insurance for the Bank could have a material adverse effect on our earnings.

All FDIC-insured depository institutions must pay an annual assessment to provide funds for the payment of interest on bonds issued by the Financing Corporation, a federal corporation chartered under the authority of the Federal Housing Finance Board. The bonds, commonly referred to as FICO bonds, were issued to capitalize the Federal Savings and Loan Insurance Corporation. The FDIC established the FICO assessment rates effective for the first half of 2004 at approximately 1.54 cents for each $100 of assessable deposits. The FICO assessments are adjusted quarterly to reflect changes in the assessment bases of the FDIC’s insurance funds and do not vary depending on a depository institution’s capitalization or supervisory evaluations.

Interstate Banking and Branching

Banks have the ability, subject to certain State restrictions, to acquire by acquisition or merger branches outside its home state. The establishment of new interstate branches is also possible in those states with laws that expressly permit it. Interstate branches are subject to certain laws of the states in which they are located. Competition may increase further as banks branch across state lines and enter new markets.

Community Reinvestment Act and Fair Lending Developments

The Bank is subject to certain fair lending requirements and reporting obligations involving home mortgage lending operations and Community Reinvestment Act (“CRA”) activities. The CRA generally requires the federal banking agencies to evaluate the record of a financial institution in meeting the credit needs of its local communities, including low- and moderate-income neighborhoods. A bank may be subject to substantial penalties and corrective measures for a violation of certain fair lending laws. The federal banking agencies may take compliance with such laws and CRA obligations into account when regulating and supervising other activities. Furthermore, financial institutions are subject to annual reporting and public disclosure requirements for certain written agreements that are entered into between insured depository institutions or their affiliates and non-governmental entities or persons that are made pursuant to, or in connection with, the fulfillment of the CRA.

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A bank’s compliance with its CRA obligations is based on a performance-based evaluation system which bases CRA ratings on an institution’s lending service and investment performance. When a bank applies for approval to acquire another bank, the banking regulators will review the assessment of each subsidiary bank of the applicant bank holding company, and such records may be the basis for denying the application. Prior to the consolidation of Greater Bay’s subsidiary banks, the results of the most recent exam for each of the banks were as follows:

Federal Home Loan Bank System

The Bank is a member of the Federal Home Loan Bank (“FHLB”) of San Francisco. Among other benefits, each FHLB serves as a reserve or central bank for its members within its assigned region. Each FHLB is financed primarily from the sale of consolidated obligations of the FHLB system. Each FHLB makes available loans or advances to its members in compliance with the policies and procedures established by the Board of Directors of the individual FHLB. As an FHLB member, the Bank would be required to own capital stock in an FHLB in an amount equal to the greater of:

A new capital plan of the FHLB of San Francisco was approved by the Federal Housing Finance Board and will be implemented on April 1, 2004. The new capital plan incorporates a single class of stock with a par value of $100 per share, and may be issued, exchanged, redeemed, and repurchased only at par value. Each member must own stock in an amount equal to the greater of:

The new capital stock is redeemable with five years’ written notice, subject to certain conditions.

We do not believe that the initial implementation of the FHLB of San Francisco’s new capital plan as approved will have a material impact upon our financial condition, cash flows, or results of operations. However, the Bank could be required to purchase as much as 50% additional capital stock or sell as much as 50% of its proposed capital stock requirement at the discretion of the FHLB of San Francisco.

Federal Reserve System

The Federal Reserve requires all depository institutions to maintain non-interest bearing reserves at specified levels against their transaction accounts (primarily checking, NOW, and Super NOW checking accounts) and non-personal time deposits. At December 31, 2003, the Bank was in compliance with these requirements.

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Nonbank Subsidiaries

Greater Bay’s nonbank subsidiaries also are subject to regulation by the Federal Reserve and other applicable federal and state agencies. ABD, our insurance brokerage subsidiary is subject to regulation by applicable state insurance regulatory agencies. ABD’s securities brokerage subsidiary is regulated by the SEC, the National Association of Securities Dealers, Inc. and applicable state securities regulators. Other nonbank subsidiaries are subject to the laws and regulations of both the federal government and the various states in which they conduct business.

Employees

At December 31, 2003, we had 1,710 full-time employees. None of the employees are covered by a collective bargaining agreement. We consider our employee relations to be satisfactory.

Website

Our website address is www.gbbk.com. We make available free of charge on our website our annual report on Form 10-K, our quarterly reports on Form 10-Q and our current reports on Form 8-K as soon as reasonably practicable after we file such reports with the SEC. None of the information on or hyperlinked from our website is incorporated into this Annual Report on Form 10-K.

Factors That May Affect Future Results of Operations

In addition to the other information contained in this report, the following risks may affect us. If any of these risks occurs, our business, financial condition or operating results could be adversely affected.

Changes in market interest rates may adversely affect our performance.

Our earnings are impacted by changing interest rates. Changes in interest rates impact the demand for new loans, the credit profile of existing loans, the rates received on loans and securities and rates paid on deposits and borrowings. The relationship between the rates received on loans and securities and the rates paid on deposits and borrowings is known as interest rate spread. Given our current volume and mix of interest-bearing liabilities and interest-earning assets, our interest rate spread could be expected to increase during times of rising interest rates and, conversely, to decline during times of falling interest rates. Significant fluctuations in interest rates may have an adverse effect on our business, financial condition and results of operations.

We are subject to government regulation that could limit or restrict our activities, which in turn could adversely impact our operations.

The financial services industry is regulated extensively. Federal and state regulation is designed primarily to protect the deposit insurance funds and consumers, and not primarily for the benefit our shareholders. These regulations can sometimes impose significant limitations on our operations. In addition, these regulations are constantly evolving and may change significantly over time. Significant new laws or changes in existing laws or repeal of existing laws may cause our results to differ materially. Further, federal monetary policy, particularly as implemented through the Federal Reserve System, significantly affects credit conditions for us.

Our Bay Area business focus and economic conditions in the Bay Area could adversely affect our operations.

Our Bay Area business focus could adversely affect our operations if economic conditions in the Bay Area deteriorated. Our operations are located in Northern California and concentrated primarily in Alameda, Contra Costa, Marin, Monterey, San Francisco, San Mateo, Santa Cruz, Santa Clara and Sonoma Counties, which includes the area known as the “Silicon Valley.” As a result of this geographic concentration, our results depend largely upon economic and business conditions in these areas. The economy in our market areas has exhibited weakness.

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Many publicly and privately held technology firms have experienced a decline in their stock prices and valuations. At the same time, firms in the technology industry have experienced greater difficulty than in the past in obtaining capital and funding. The inability of such firms to obtain necessary capital and funding has adversely affected existing business and resulted in a slowdown in the growth of the technology industry. A prolonged or further decline in economic and business conditions in our market areas, particularly in the technology and real estate industries on which the Bay Area depends, could have a material impact on the quality of our loan portfolio or the demand for our products and services, which in turn may have a material adverse effect on our results of operations. A continued weakening in the national economy might further exacerbate local economic conditions. The extent of the future impact of these events on economic and business conditions cannot be predicted.

Competition may adversely affect our performance.

The financial services business in our market areas is highly competitive. It is becoming increasingly competitive due to changes in regulation, technological advances, and the accelerating pace of consolidation among financial services providers. We face competition both in attracting deposits and in making loans. We compete for loans principally through the interest rates and loan fees we charge and the efficiency and quality of services we provide. Increasing levels of competition in the banking and financial services businesses may reduce our market share or cause the prices we charge for our services to fall. Our results may differ in future periods depending upon the nature or level of competition.

If a significant number of borrowers, guarantors and related parties fail to perform as required by the terms of their loans, we will sustain losses.

A significant source of risk arises from the possibility that losses will be sustained if a significant number of our borrowers, guarantors and related parties fail to perform in accordance with the terms of their loans. We have adopted underwriting and credit monitoring procedures and credit policies, including the establishment and review of the allowance for credit losses, that management believes are appropriate to minimize this risk by assessing the likelihood of nonperformance, tracking loan performance and diversifying our credit portfolio. These policies and procedures, however, may not prevent unexpected losses that could materially adversely affect our results of operations.

Failure to successfully execute our charter integration plan and our growth strategy could adversely affect our performance.

On February 1, 2004, we completed the merger of our 11 bank subsidiaries into a single national bank that will be regulated by the OCC. Our financial performance and profitability will depend on our ability to successfully integrate the systems of these eleven banking subsidiaries into a single system over an estimated 18 month period. Although the existing banking subsidiaries currently operate on substantially identical systems and share many common back-office operations, there can be no assurance that unforeseen issues relating to the assimilation of these subsidiaries will not adversely affect us.

In addition, any future acquisitions and our continued growth may present operating and other problems that could have an adverse effect on our business, financial condition and results of operations. Our financial performance will also depend on our ability to maintain profitable operations through implementation of our Regional Community Banking Philosophy, which is described earlier. Accordingly, there can be no assurance that we will be able to execute our growth strategy or maintain the level of profitability that we have recently experienced.

Recent accounting changes may give rise to a future regulatory capital event that would entitle the trusts created to facilitate the trust preferred offerings to redeem the Trust Preferred Securities and may also reduce our consolidated capital ratios.

In accordance with the provisions of Financial Accounting Standard Board (“FASB”) Interpretation No. (“FIN”) 46, “Consolidation of Variable Interest Entities” (“FIN 46”), we have deconsolidated the six subsidiary

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trusts which have issued Trust Preferred Securities for Greater Bay, and their financial position and results of operations are not included in our consolidated financial position and results of operations. Accordingly, the Trust Preferred Securities which had previously been reported as a liability have been replaced by the subordinated debt issued by Greater Bay to the trusts.

Under applicable regulatory guidelines, a portion of the Trust Preferred Securities will qualify as Tier I capital, and the remaining portion will qualify as Tier II capital. Under applicable regulatory guidelines, all $204.0 million of the outstanding Trust Preferred Securities qualify as Tier I Capital at December 31, 2003. On July 2, 2003, the Federal Reserve Board issued Supervisory Letter (SR 03-13) which preserves the historical capital treatment of TPS as Tier I capital despite the deconsolidation of these securities. That Supervisory Letter remained in effect at December 31, 2003, and we continue to include these securities in our Tier I capital. There remains the potential that this determination by the Federal Reserve Board may change at a later date.

If Tier I capital treatment for our Trust Preferred Securities were disallowed, there would be a reduction in our consolidated capital ratios. The following table shows as of December 31, 2003 (1). Greater Bay’s current capital position, (2). our pro forma capital position if the Federal Reserve Board granted Tier II status to our Trust Preferred Securities, (3). our pro forma capital position if the Federal Reserve Board excludes entirely our Trust Preferred Securities from capital and (4). the minimum regulatory capital requirements for well-capitalized status.

As the table shows, we would remain “well-capitalized” under Federal Reserve guidelines in the event that the Federal Reserve elected to change its position with regards to the capital treatment of Trust Preferred Securities. If Tier 1 capital treatment were disallowed, then we could redeem the Trust Preferred Securities pursuant to the terms of the Trust Preferred Securities, and have the ability to identify and obtain alternative sources of capital.

ITEM 2.    PROPERTIES.

We occupy our administrative offices under a lease which, including options to renew, expires in 2007. We own ten of our offices and lease 71 additional offices which are primarily located in the San Francisco Bay Area. Those leases expire under various dates, including options to renew, through December 2017.

We believe our present facilities are adequate for our current needs but anticipate the need for additional facilities as we continue to grow. We believe that, if necessary, we could secure suitable alternative facilities on similar terms without adversely affecting operations.

ITEM 3.    LEGAL PROCEEDINGS.

From time to time, we are involved in certain legal proceedings arising in the normal course of our business. Management believes that the outcome of these matters will not have a material adverse effect on us.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

There was no submission of matters to a vote of securities holders during the fourth quarter of the year ended December 31, 2003.

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PART II

Our common stock is traded on the Nasdaq National Market (“Nasdaq”) under the symbol “GBBK”. The quotations shown reflect for the periods indicated the high and low closing sales prices for our common stock as reported by Nasdaq.

There were 3,536 common shareholders of record and 107 convertible preferred shareholders of record at December 31, 2003.

For information on the ability of the Bank to pay dividends and make loans to Greater Bay, see “MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS—Financial Condition—Liquidity and Cash Flow” and Note 22 of the NOTES TO CONSOLIDATED FINANCIAL STATEMENTS.

Information regarding Selected Consolidated Financial Data appears on page A-1 under the caption “Selected Financial Information” and is incorporated herein by reference.

Information regarding MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS appears on pages A-2 through A-27 under the caption “MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS” and is incorporated herein by reference.

Information regarding Quantitative and Qualitative Disclosures About Market Risk appears on pages A-28 through A-31 under the caption “QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK” and is incorporated herein by reference.

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Information regarding Financial Statements and Supplementary Data appears on A-32 through A-85 under the caption “CONSOLIDATED BALANCE SHEETS,” “CONSOLIDATED STATEMENTS OF OPERATIONS,” “CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME,” “CONSOLIDATED STATEMENTS OF SHAREHOLDERS’ EQUITY,” “CONSOLIDATED STATEMENTS OF CASH FLOWS” and “NOTES TO CONSOLIDATED FINANCIAL STATEMENTS” and is incorporated herein by reference.

None.

In accordance with Rule 13a-15(b) of the Exchange Act, as of the end of the year ended December 31, 2003, we carried out an evaluation under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of our disclosure controls and procedures as defined in Rule 13a-15(e) and 15d-15(e) under the Exchange Act. Based on that evaluation, our Chief Executive Officer and Chief Financial Officer have concluded that our disclosure controls and procedures are effective.

During the quarter ended December 31, 2003, there have been no changes in our internal controls over financial reporting that has materially affected, or are reasonably likely to materially affect, these controls.

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PART III

We intend to file a definitive proxy statement for the 2004 Annual Meeting of Shareholders (the “Proxy Statement”) with the SEC within 120 days of December 31, 2003. Information regarding directors of Greater Bay (including information about Greater Bay’s “Audit Committee Financial Expert”) will appear under the caption “DISCUSSION OF THE PROPOSALS RECOMMENDED BY THE BOARD—Proposal 1: “Election of Directors” in the Proxy Statement and is incorporated herein by reference. Information regarding compliance with Section 16(a) of the Securities Exchange Act of 1934, as amended, and executive officers will appear under the captions “INFORMATION ABOUT DIRECTORS AND EXECUTIVE OFFICERS—Section 16(a) Beneficial Ownership Reporting Compliance by Directors and Executive Officers” and “—Executive Officers” in the Proxy Statement and is incorporated herein by reference.

Greater Bay Bancorp has adopted a code of ethics applicable to all of our directors and employees, including the principal executive officer, principal financial officer and principal accounting officer. A copy of the code of ethics is filed as Exhibit 14.1 to this Annual Report on Form 10-K.

Information regarding executive compensation will appear under the captions “INFORMATION ABOUT DIRECTORS AND EXECUTIVE OFFICERS—How We Compensate Executive Officers,” “—How We Compensate Directors,” “—Employment Contracts, Termination of Employment and Change of Control Arrangements,” “—Executive Committee’s Report on Executive Compensation,” “—Compensation Committee Interlocks and Insider Participation” and “—Performance Graph” in the Proxy Statement and is incorporated herein by reference.

The following table summarizes information as of December 31, 2003 relating to equity compensation plans of Greater Bay pursuant to which grants of options, restricted stock, or other rights to acquire shares may be granted from time to time.

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Information regarding security ownership of certain beneficial owners and management and related shareholder matters will appear under the caption “INFORMATION ABOUT GREATER BAY STOCK OWNERSHIP” in the Proxy Statement and is incorporated herein by reference.

Information regarding certain relationships and related transactions will appear under the caption “INFORMATION ABOUT DIRECTORS AND EXECUTIVE OFFICERS—Certain Relationships and Related Transactions” in the Proxy Statement and is incorporated herein by reference.

Information regarding fees paid to PricewaterhouseCoopers LLP, our independent accountants, will appear under the caption “Principal Accountants Fees and Services” in the Proxy Statement and is incorporated herein by reference.

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PART IV

(a)    1.    Financial Statements

The following documents are filed as part of this report:

2.    Financial Statement Schedules

Not applicable.

3.    Exhibits

See Item 15(c) below.

(b)    Reports on Form 8-K

During the fourth quarter of 2003, the Company filed the following Current Reports on Form 8-K: (1) December 2, 2003 (reported under Item 5, 7 and 9) announcing the promotion of the Company’s Chief Operating Officer to Chief Executive Officer; (2) October 29, 2003 (reporting under Item 5, 7, and 9) announcing the charter consolidation; (3) October 27, 2003 (reporting under Item 5, 7, and 9) Greater Bay Bancorp’s slide presentation; (4) October 22, 2003, (reporting under Item 12) release of 2003 third quarter financial results; (5) October 7, 2003 (reporting under Item 5, 7, and 9) announcing the promotion of the Company’s Chief Operating Officer to President and the retirement of the Company’s Chief Financial Officer; release of 2003 third quarter guidance.

(c)    Exhibits Required by Item 601 of Regulation S-K

Reference is made to the Exhibit Index on pages 28 through 31 for exhibits filed as part of this report.

(d)    Additional Financial Statements

Not applicable.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized, on the 27^th day of February 2004.

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

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ANNUAL REPORT ON FORM 10-K (CONTINUED)

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EXHIBIT INDEX

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EXHIBIT INDEX (Continued)

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EXHIBIT INDEX (Continued)

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EXHIBIT INDEX (Continued)

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SELECTED FINANCIAL INFORMATION

The following table represents the selected financial information at and for the five years ended December 31, 2003: