BMRC US Equity☆

bmrc-20211231

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2021

OR

☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from __________________ to __________________

Commission File Number 001-33572

Bank of Marin Bancorp

(Exact name of Registrant as specified in its charter)

(Address of principal executive office) (Zip Code)

Registrant’s telephone number, including area code: (415) 763-4520

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

None

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

Title of each class Trading symbol Name of each exchange on which registered

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.

Yes ☐No☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.

Yes ☐No☒

Note - checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Exchange Act from their obligations under these sections.

Indicate by check mark whether the registrant (1) has filed all reports 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☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted 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☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smaller reporting company,” and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer ☐ Accelerated filer ☒

Non-accelerated filer ☐ Smaller reporting company ☐

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

Indicate by check mark if the registrant is a shell company, as defined in Rule 12b-2 of the Exchange Act.

Yes ☐ No ☒

As of June 30, 2021, the last business day of the registrant's most recently completed second fiscal quarter, the aggregate market value of the voting common equity held by non-affiliates, based upon the closing price per share of the registrant's common stock as reported by the Nasdaq, was approximately $390 million. For the purpose of this response, directors and certain officers of the Registrant are considered affiliates at that date.

As of February 28, 2022, there were 15,939,659 shares of common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the registrant's Proxy Statement for the Annual Meeting of Shareholders to be held on May 10, 2022 are incorporated by reference into Part III.

TABLE OF CONTENTS

PART I Page-4

Forward-Looking Statements Page-4

ITEM 1. BUSINESS Page-4

ITEM 1A. RISK FACTORS Page-12

ITEM 1B. UNRESOLVED STAFF COMMENTS Page-20

ITEM 2. PROPERTIES Page-20

ITEM 3. LEGAL PROCEEDINGS Page-20

ITEM 4. MINE SAFETY DISCLOSURES Page-20

PART II Page-21

ITEM 6. [RESERVED] Page-23

Forward-Looking Statements Page-23

Critical Accounting Estimates Page-23

RESULTS OF OPERATIONS

Financial Highlights Page-26

Executive Summary Page-27

Net Interest Income Page-29

Provision for Credit Losses Page-31

Non-Interest Income Page-31

Non-Interest Expense Page-32

Provision for Income Taxes Page-33

FINANCIAL CONDITION Page-33

Investment Securities Page-33

Loans Page-36

Allowance for Credit Losses Page-39

Other Assets Page-42

Deposits Page-42

Borrowings Page-43

Deferred Compensation Obligations Page-43

Capital Adequacy Page-44

Liquidity and Capital Resources Page-44

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK Page-45

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA Page-46

Report of Independent Registered Public Accounting Firm Page-47

Management's Report on Internal Control over Financial Reporting Page-50

Consolidated Statements of Condition Page-51

Consolidated Statements of Comprehensive Income Page-52

Consolidated Statements of Changes in Stockholders' Equity Page-53

Consolidated Statements of Cash Flows Page-54

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS Page-55

Note 1: Summary of Significant Accounting Policies Page-55

Note 2: Investment Securities Page-67

Note 3: Loans and Allowance for Credit Losses Page-72

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Note 4: Bank Premises and Equipment Page-79

Note 5: Bank Owned Life Insurance Page-80

Note 6: Deposits Page-80

Note 7: Borrowings Page-81

Note 8: Stockholders' Equity and Stock Plans Page-81

Note 9: Fair Value of Assets and Liabilities Page-86

Note 10: Benefit Plans Page-88

Note 11: Income Taxes Page-89

Note 12: Commitments and Contingencies Page-91

Note 13: Concentrations of Credit Risk Page-92

Note 14: Derivative Financial Instruments and Hedging Activities Page-93

Note 15: Regulatory Matters Page-94

Note 16: Financial Instruments with Off-Balance Sheet Risk Page-95

Note 18: Merger Page-98

ITEM 9A. CONTROLS AND PROCEDURES Page-102

ITEM 9B. OTHER INFORMATION Page-103

PART III Page-103

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE Page-103

ITEM 11. EXECUTIVE COMPENSATION Page-103

ITEM 14. PRINCIPAL ACCOUNTANT FEES AND SERVICES Page-103

PART IV Page-104

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES Page-104

SIGNATURES Page-106

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PART I

Forward-Looking Statements

This Annual Report on Form 10-K includes forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, (the "1933 Act") and Section 21E of the Securities Exchange Act of 1934, as amended, (the "1934 Act"). Those sections of the 1933 Act and 1934 Act provide a "safe harbor" for forward-looking statements to encourage companies to provide prospective information about their financial performance so long as they provide meaningful, cautionary statements identifying important factors that could cause actual results to differ significantly from projected results.

Our forward-looking statements include descriptions of plans or objectives of management for future operations, products or services, and forecasts of revenues, earnings or other measures of economic performance. Forward-looking statements can be identified by the fact that they do not relate strictly to historical or current facts. They often include the words "believe," "expect," "intend," "estimate" or words of similar meaning, or future or conditional verbs preceded by "will," "would," "should," "could" or "may."

Forward-looking statements are based on management's current expectations regarding economic, legislative, and regulatory issues that may affect our earnings in future periods. A number of factors, many of which are beyond management’s control, could cause future results to vary materially from current management expectations. Such factors include, but are not limited to, general economic conditions and the economic uncertainty in the United States and abroad, including changes in interest rates, California's unemployment rate, deposit flows, real estate values, and expected future cash flows on loans and securities; costs or effects of acquisitions; competition; changes in accounting principles, policies or guidelines; changes in legislation or regulation (including the Coronavirus Aid, Relief and Economic Security Act of 2020, as amended, and the Economic Aid to Hard-Hit Small Businesses, Nonprofits and Venues Act of 2020); our borrowers’ actual payment performance as loan deferrals related to the COVID-19 pandemic expire, including the potential adverse impact of loan modifications and payment deferrals implemented consistent with recent regulatory guidance; natural disasters (such as wildfires and earthquakes in our area); adverse weather conditions; interruptions of utility service in our markets for sustained periods; and other economic, competitive, governmental, regulatory and technological factors (including external fraud and cybersecurity threats) affecting our operations, pricing, products and services; and successful integration of acquisitions.

Important factors that could cause results or performance to materially differ from those expressed in our prior forward-looking statements are detailed in ITEM 1A, Risk Factors section of this report. Forward-looking statements speak only as of the date they are made. We do not undertake to update forward-looking statements to reflect circumstances or events that occur after the date the forward-looking statements are made or to reflect the occurrence of unanticipated events.

ITEM 1. BUSINESS

Bank of Marin (the “Bank”) was incorporated in August 1989, received its charter from the California Superintendent of Banks (now the Department of Financial Protection and Innovation or "DFPI") and commenced operations in January 1990. The Bank is an insured bank by the Federal Deposit Insurance Corporation (“FDIC”). Bank of Marin Bancorp ("Bancorp") was formed in 2007 and the Bank became its sole subsidiary when each share of Bank common stock was exchanged for one share of Bancorp common stock. Bancorp is listed on the Nasdaq Stock Market under the symbol BMRC. Upon formation of the holding company, Bancorp became subject to regulation under the Bank Holding Company Act of 1956, as amended, and reporting and examination requirements by the Board of Governors of the Federal Reserve System ("Federal Reserve"). Bancorp files periodic reports and proxy statements with the Securities and Exchange Commission pursuant to the Securities Exchange Act of 1934, as amended.

References in this report to “Bancorp” mean Bank of Marin Bancorp, parent holding company for the Bank. References to “we,” “our,” “us” mean the holding company and the Bank that are consolidated for financial reporting purposes.

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Virtually all of our business is conducted through Bancorp's subsidiary, Bank of Marin, which is headquartered in Novato, California. In addition to our headquarters, we operate 31 retail branches and 8 commercial banking offices across 10 counties - Alameda, Amador, Contra Costa, Marin, Napa, Placer, Sacramento, San Francisco, San Mateo and Sonoma counties, with a strong emphasis on supporting the local communities. Our customer base is made up of business, not-for-profit and personal banking relationships from the communities within our Northern California footprint. Our business banking focus is on small to medium-sized businesses, professionals and not-for-profit organizations.

We offer a broad range of commercial and retail deposit and lending programs designed to meet the needs of our target markets. Our lending categories include commercial real estate loans, commercial and industrial loans (including small business loans), construction financing, consumer loans, and home equity lines of credit. Through third-party vendors, we offer merchant and payroll services, a commercial equipment leasing program and consumer credit cards. Other products and services include Apple Pay®, Samsung Pay®, Google Pay®, Zelle®, Positive Pay (fraud detection tool), and solutions for clients with cash management needs such as Cash Vault and SafePoint®.

We offer a variety of personal and business checking and savings accounts, and a number of time deposit alternatives, including time certificates of deposit, Individual Retirement Accounts (“IRAs”), Health Savings Accounts ("HSA"), Certificate of Deposit Account Registry Service® ("CDARS"), Insured Cash Sweep® ("ICS"), and Demand Deposit MarketplaceSM ("DDM Sweep") accounts. CDARS, ICS and DDM Sweep accounts are networks through which we offer full FDIC insurance coverage in excess of the regulatory maximum by placing deposits in multiple banks participating in the networks. We also offer deposit options including mobile deposit, remote deposit capture, Automated Clearing House (“ACH”) services, wire transfers, and image lockbox services.

Automated teller machines (“ATM's”) are available at most branch locations. Our ATM network is linked to the PLUS, CIRRUS and NYCE networks, as well as to a network of nation-wide surcharge-free ATM's called MoneyPass. We also offer our depositors 24-hour access to their accounts by telephone and through digital banking services available to personal and business account holders.

We offer Wealth Management and Trust Services (“WMTS”), which include customized investment portfolio management, financial planning, trust administration, estate settlement and custody services. We also offer 401(k) plan services to small and medium-sized businesses through a third-party vendor.

We make international banking services available to our customers indirectly through other financial institutions with whom we have correspondent banking relationships.

We hold no patents, licenses (other than licenses required by the appropriate banking regulatory agencies), franchises or concessions. The Bank has registered the service marks "The Spirit of Marin," the words “Bank of Marin,” the Bank of Marin logo, and the Bank of Marin tagline, “Committed to your business and our community” with the United States Patent & Trademark Office. In addition, Bancorp has registered the service marks for the words “Bank of Marin Bancorp” and for the Bank of Marin Bancorp logo with the United States Patent & Trademark Office. All service marks registered by Bancorp or the Bank are registered on the United States Patent & Trademark Office Principal Register.

Market Area

Our primary market area consists of Alameda, Amador, Contra Costa, Marin, Napa, Placer, Sacramento, San Francisco, San Mateo and Sonoma counties. Our customer base is primarily made up of business, not-for-profit and personal banking relationships within these market areas. As of December 31, 2021, the majority of our deposits were in Marin, Sacramento and southern Sonoma counties, and approximately 60% of our deposits were from businesses and 40% from individuals.

As discussed in Note 18 to the Consolidated Financial Statements in ITEM 8 of this report, in August 2021, we expanded our presence in Amador, Placer, Sacramento and Sonoma counties through the acquisition of American River Bankshares and its subsidiary American River Bank. This resulted in the addition of $898.4 million of assets and the assumption of $816.6 million of liabilities as of the August 6, 2021 merger date, as well as the addition of 10 branch offices.

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Competition

The banking business in California generally, and in our market area specifically, is highly competitive with respect to attracting both loan and deposit relationships. The increasingly competitive environment is affected by changes in regulation, interest rates, technology and product delivery systems, and consolidation among financial service providers. The banking industry is seeing strong competition for quality loans, with larger banks expanding their activities to attract businesses that are traditionally community bank customers. In all of our ten counties, we have significant competition from nationwide banks with much larger branch networks and greater financial resources, as well as credit unions and other local and regional banks. Nationwide banks have the competitive advantages of developing data analytics and artificial intelligence tools and other technological platforms. Large commercial banks also have substantially greater lending limits and the ability to offer certain services which are not offered directly by us. Other competitors for depositors' funds are money market mutual funds and non-bank financial institutions such as brokerage firms and insurance companies.

We differentiate ourselves from the numerous, and often larger, financial institutions in our primary market area with a business model built on relationship banking, disciplined fundamentals and commitment to the communities we serve. The Bank's experienced professionals deliver innovative and custom financing, with a deep local market knowledge and a personal understanding of each customer's unique needs.

In Marin County, we have the fourth largest market share of total depositsat 10.5%, based upon FDIC deposit market share data as of June 30, 20211 (most recent data available). A significant driver of our franchise value is the growth and stability of our deposits, a low-cost funding source for our loan portfolio.

Human Capital Resources

At December 31, 2021, we employed 328 full-time equivalent staff. The actual number of employees, including part-time employees, at year-end 2021 included seven executive officers, 144 other corporate officers and 190 staff. None of our employees are presently represented by a union or covered by a collective bargaining agreement.

We offer a competitive total compensation package including a comprehensive benefits program to our employees designed to attract, retain and motivate employees, as well as to align with our performance, including employee ownership through our Employee Stock Ownership Plan. We regularly compare compensation and benefits with peer companies and market data, making adjustments as needed to ensure compensation stays competitive. We are continually investing in our workforce through employee development, education and training.

We strive to attract, develop, retain and plan for succession of key talent and executives to achieve our strategic objectives. We pride ourselves on creating an open, diverse, and transparent culture that celebrates collaboration and recognizes employees at all levels. We believe that the wide array of perspectives that result from such diversity promotes Legendary Service and business success. We continue to learn and grow, and our current initiatives reflect our ongoing efforts around a more diverse, inclusive and equitable workplace.

In order to develop a workforce that aligns with our corporate values, we regularly sponsor local community events so that our employees can better integrate themselves in and support our communities. We believe that our employees’ well-being and personal and professional development is fostered by our outreach to the communities we serve. Our employees’ desire for active community involvement enables us to sponsor a number of local community events and initiatives, including funding and volunteering for youth mentorship and financial literacy programs to enhance educational opportunities and sponsoring local chambers of commerce and economic development corporations to foster economic vitality.

We recognize that employees who are engaged and committed to their work and workplace contribute meaningfully to our success. On a regular basis, we solicit employee feedback through a confidential, company-wide survey on culture, management, career opportunities, compensation, and benefits. The results of this survey are reviewed and used to update employee programs, initiatives, and communications. We believe that our employee relations are good. We have been recognized as one of the “Best Places to Work” by the North Bay Business Journal.

1Source: S&P Global Market Intelligence of New York, New York

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COVID-19 Pandemic-Related Response

Since the onset of the pandemic and national emergency, we have taken actions to ensure the health and safety of employees and customers. To protect the health of everyone, we have implemented COVID-19 safety protocols and continue to actively monitor federal, state and local guidelines and information related to COVID-19 to ensure the safety of our employees and customers. No employees have been laid off and no employees have had their pay reduced.

SUPERVISION AND REGULATION

Bank holding companies and banks are extensively regulated under both federal and state law. The following discussion summarizes certain significant laws, rules and regulations affecting Bancorp and the Bank.

Bank Holding Company Regulation

Upon formation of the bank holding company on July 1, 2007, we became subject to regulation under the Bank Holding Company Act of 1956, as amended (“BHCA”) which subjects Bancorp to Federal Reserve reporting and examination requirements. Under the Federal Reserve law and regulations, a bank holding company is required to serve as a source of financial and managerial strength to its subsidiary banks. Under this requirement, Bancorp is expected to commit resources to support the Bank, including at times when Bancorp may not be in a financial position to provide such resources, and it may not be in Bancorp's, or Bancorp's shareholders’ or creditors’, best interests to do so. In addition, any capital loans Bancorp makes to the Bank are subordinate in right of payment to depositors and to certain other indebtedness of the Bank. The BHCA regulates the activities of holding companies including acquisitions, mergers and consolidations and, together with the Gramm-Leach Bliley Act of 1999, the scope of allowable banking activities. Bancorp is also a bank holding company within the meaning of the California Financial Code. As such, Bancorp and its subsidiaries are subject to examination by, and may be required to file reports with, the DFPI.

Bank Regulation

Banking regulations are primarily intended to protect consumers, depositors' funds, federal deposit insurance funds and the banking system as a whole. These regulations affect our lending practices, consumer protections, capital structure, investment practices and dividend policy.

As a state chartered bank, we are subject to regulation, supervision and examination by the DFPI. We are also subject to regulation, supervision and periodic examination by the FDIC. If, as a result of an examination of the Bank, the FDIC or the DFPI should determine that the financial condition, capital resources, asset quality, earnings prospects, management, liquidity, or other aspects of our operations are unsatisfactory, or that we have violated any law or regulation, various remedies are available to those regulators including issuing a “cease and desist” order, monetary penalties, restitution, restricting our growth or removing officers and directors.

The Bank addresses the many state and federal regulations it is subject to through a comprehensive compliance program.

Safety and Soundness Standards (Risk Management)

The federal banking agencies have adopted guidelines that establish operational and managerial standards to promote the safety and soundness of federally insured depository institutions. The guidelines set forth standards for internal controls, information systems, internal audit systems, loan documentation, credit underwriting, interest rate exposure, asset growth, compensation, fees and benefits, asset quality and earnings.

During the past decade, the bank regulatory agencies have increasingly emphasized the importance of sound risk management processes and strong internal controls when evaluating the activities of the financial institutions they supervise. Properly managing risks has been identified as critical to the conduct of safe and sound banking activities and has become even more important as new technologies, product innovation, and the size and speed of financial transactions have changed the nature of banking markets. The agencies have identified a spectrum of risks facing a banking institution including, but not limited to, credit, market, liquidity, operational, legal, and reputational. In particular, recent regulatory pronouncements have focused on operational risk, which arises from

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the potential that inadequate information systems, operational problems, breaches in internal controls, fraud, or unforeseen catastrophes will result in unexpected losses. New products and services, third-party risk management and cybersecurity are critical sources of operational risk that financial institutions are expected to address in the current environment. The Board of Directors and various sub-committees oversee Bancorp's consolidated enterprise risk management program that ensures the adequacy of policies, procedures, tolerance levels, risk measurement systems, monitoring processes, management information systems and internal controls.

Dividends and Stock Repurchases

Bancorp's ability to pay dividends to its shareholders may be affected by both general corporate law considerations and the policies of the Federal Reserve applicable to bank holding companies. As a California corporation, Bancorp is subject to the limitations of California law, which allows a corporation to distribute cash or property to shareholders, including a dividend or repurchase or redemption of shares, if the corporation meets certain tests based on its performance and financial condition. Bancorp's primary source of cash is dividends received from the Bank. Prior to any distribution from the Bank to Bancorp, we ensure that the dividend computations comply with the provisions of the California Financial Code and regulations set forth by the DFPI and the FDIC. Refer to Note 8 to the Consolidated Financial Statements, under the heading “Dividends” in ITEM 8 of this report for more information.

FDIC Insurance Assessments

The FDIC insures our customers' deposits to the maximum amount permitted by law, which is currently $250,000 per depositor, based on the 2010 Dodd-Frank Wall Street Reform and Consumer Protection Act (the “Dodd-Frank Act”).

FDIC insurance coverage is funded by the FDIC's assessment on insured depository institutions like us and FDIC's annual base assessment rates are currently between 1.5 and 40 basis points on the depository institution's quarterly average consolidated total assets minus average tangible equity. Base assessment rates for banks vary depending on whether a depository institution is small or large and highly complex per FDIC's definition. In deriving the base assessment rate, the FDIC applies financial ratios, scorecards, and other financial measures to determine a bank's ability to withstand financial stress.

Community Reinvestment Act

Congress enacted the Community Reinvestment Act (“CRA”) in 1977 to encourage financial institutions to meet the credit needs of the communities in which they are located. All banks and thrifts have a continuing and affirmative obligation, consistent with safe and sound operations, to help meet the credit needs of their entire communities, including low and moderate income neighborhoods. Regulatory agencies rate each bank's performance in assessing and meeting these credit needs. The Bank is committed to serving the credit needs of the communities in which we do business, and it is our policy to respond to all creditworthy segments of our market. As part of its CRA commitment, the Bank maintains strong philanthropic ties to the community. We invest in affordable housing projects that help economically disadvantaged individuals and residents of low- and moderate-income census tracts, in each case consistent with our long-established prudent underwriting practices. We also donate to, invest in and volunteer with organizations that serve the communities in which we do business, especially low- and moderate-income individuals. These organizations offer educational and health programs to economically disadvantaged students and families, community development services and affordable housing programs. We offer CRA reportable small business, small farm and community development loans within our assessment areas. The CRA requires a depository institution's primary federal regulator, in connection with its examination of the institution, to assess the institution's record in meeting CRA requirements. The regulatory agency's assessment of the institution's record is made available to the public. This record is taken into consideration when the institution establishes a new branch that accepts deposits, relocates an office, applies to merge or consolidate, or expands into other activities. The FDIC assigned a “Satisfactory” rating to Bank of Marin's CRA performance examination based on their most recent examination completed in January 2021, which was performed under the large bank requirements.

In December 2019, the FDIC and the OCC announced a proposal to modernize the agencies’ regulations under the CRA that have not been substantively updated for nearly 25 years. In order to increase transparency for CRA exams, the proposal clarifies what qualifies for credit under the CRA, enabling banks and their partners to better

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implement lending and deposit activities that can benefit communities. The proposal also updates the definition of a small business loan and creates an additional definition of “assessment area” tied to where deposits are located, in part to address changes that have occurred due to the rise in digital banking, ensuring that banks continue to provide loans and other services to low- and moderate-income individuals and businesses in their communities. Although the proposed rule was never finalized by the FDIC, it is expected that there will be interagency efforts to update and finalize a rule soon.

Anti-Money-Laundering Regulations

A series of banking laws and regulations beginning with the Bank Secrecy Act in 1970 requires banks to prevent, detect, and report illicit or illegal financial activities to the federal government to prevent money laundering, international drug trafficking, and terrorism. Under the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001, financial institutions are subject to prohibitions against specified financial transactions and account relationships, requirements regarding the Customer Identification Program, as well as enhanced due diligence and “know your customer” standards in their dealings with high risk customers, foreign financial institutions, and foreign individuals and entities. In 2016, Customer Due Diligence Rules under the Bank Secrecy Act clarified and strengthened customer due diligence requirements. These rules contained explicit customer due diligence requirements, which included a new requirement to identify and verify the identity of beneficial owners of legal entity customers. In 2020, the Anti-Money Laundering Act ("AMLA 2020") became law. Among its many provisions, AMLA 2020 provides for: 1) expanded whistleblower rewards and protections; 2) the establishment of a beneficial ownership registration database that will be implemented by the Financial Crimes Enforcement Network ("FinCEN"); and 3) new Bank Secrecy Act violations and enhanced penalties for repeat and egregious violators.

Privacy and Data Security

The Gramm-Leach Bliley Act (“GLBA”) of 1999 imposes requirements on financial institutions with respect to consumer privacy and the disclosure of non-public personal information about individuals who apply for or obtain a financial product to be used for personal, family or household purposes. The GLBA generally prohibits disclosure of consumer information to most nonaffiliated third parties unless the consumer has been given the opportunity to object and has not objected to such disclosure. Financial institutions are further required to disclose their privacy policies to consumers and the conditions under which an institution may disclose non-public information about a consumer to a nonaffiliated third party. The GLBA also directs federal regulators, including the FDIC, to prescribe standards for the security of consumer information. We are subject to such standards, as well as standards for notifying consumers in the event of a security breach. We must disclose our privacy policy to consumers and permit consumers to "opt out" of having non-public customer information disclosed to third parties. We are required to have an information security program to safeguard the confidentiality and security of customer information and to ensure proper disposal of information that is no longer needed. We notify our customers when unauthorized disclosure involves sensitive customer information that may be misused. Effective January 2020, the California Consumer Privacy Act (“CCPA”) added required notice about personal information we collect, use, share, and disclose for business purposes. The CCPA provides California residents rights regarding their personal information specifically related to exercising access, data portability and deletion rights. There are also California breach notification and disclosure requirements.

On November 23, 2021, the federal banking agencies issued a final rule requiring banking organizations that experience a computer-security incident to notify their primary Federal regulator of the occurrence of an event that rises to the level of a “notification incident.” Generally, a notification incident occurs when a banking organization has suffered a computer-security incident that has a reasonable likelihood of materially disrupting or degrading the banking organization or its operations. The rule requires an affected banking organization to notify its primary Federal regulator as soon as possible and no later than 36 hours after the banking organization has determined that a notification incident has occurred. The rule also requires bank service providers to notify each affected banking organization if that bank service provider experiences a computer-security incident that has caused, or is reasonably likely to cause, a material service disruption or degradation for four or more hours. The rule becomes effective on April 1, 2022, with a compliance date of May 1, 2022.

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Consumer Protection Regulations

Our lending activities are subject to a variety of statutes and regulations designed to protect consumers, including the CRA, Home Mortgage Disclosure Act, Fair Credit Reporting Act, Fair Lending, Fair Debt Collection Practices Act, Flood Disaster Protection Act, eSign Act, Equal Credit Opportunity Act, the Fair Housing Act, Truth-in-Lending Act ("TILA"), the Real Estate Settlement Procedures Act ("RESPA"), Protecting Tenants at Foreclosure, and the Secure and Fair Enforcement for Mortgage Licensing Act ("SAFE"). Our deposit operations are also subject to laws and regulations that protect consumer rights including Expedited Funds Availability, Truth in Savings Act ("TISA"), and Electronic Funds Transfers. Other regulatory requirements include the Unfair, Deceptive or Abusive Acts and Practices ("UDAAP"), Dodd-Frank Act, Right to Financial Privacy, Telephone Consumer Protection Act and Privacy of Consumer Financial Information. Additional rules govern check writing ability on certain interest earning accounts and prescribe procedures for complying with administrative subpoenas of financial records.

Restriction on Transactions between Bank's Affiliates

Transactions between Bancorp and the Bank are quantitatively and qualitatively restricted under Sections 23A and 23B of the Federal Reserve Act and Federal Reserve Regulation W. Section 23A places restrictions on the Bank's “covered transactions” with Bancorp, including loans and other extensions of credit, investments in the securities of, and purchases of assets from Bancorp. Section 23B requires that certain transactions, including all covered transactions, be on market terms and conditions. Federal Reserve Regulation W combines statutory restrictions on transactions between the Bank and Bancorp with Federal Reserve interpretations in an effort to simplify compliance with Sections 23A and 23B.

Capital Requirements

The Federal Deposit Insurance Act, as amended (“FDIA”), requires federal banking agencies to take prompt corrective action (“PCA”) with respect to depository institutions that do not meet minimum capital requirements. The FDIA includes the following five capital tiers: “well capitalized,” “adequately capitalized,” “undercapitalized,” “significantly undercapitalized,” and “critically undercapitalized.” A depository institution’s capital tier will depend upon how its capital levels compare with various relevant capital measures and certain other factors, as established by regulation. Bancorp's ratios exceed the required minimum ratios for capital adequacy purposes and the Bank meets the definition for "well capitalized." Undercapitalized depository institutions may be subject to significant restrictions. Banks that are categorized as "critically undercapitalized" are subject to dividend and other restrictions.

Effective January 1, 2020, the federal banking agencies' jointly-issued final rule on the community bank leverage ratio ("CBLR") provides for an optional, simplified measure of capital adequacy for qualifying community banking organizations, consistent with Section 201 of the Economic Growth, Regulatory Relief, and Consumer Protection Act (the "Economic Growth Act"). Qualifying community banking organizations are defined as having less than $10 billion in total consolidated assets that meet risk-based qualifying criteria, a CBLR of greater than 9 percent, off-balance sheet exposure of 25 percent or less of total consolidated assets, trading assets and liabilities of 5 percent or less of total consolidated assets, and cannot be an advanced approaches institution. Such a community banking organization would not be subject to other risk-based and leverage capital requirements (including the Basel III and Basel IV requirements) and would be considered to have met the "well capitalized" ratio requirements. The CBLR is determined by dividing a financial institution’s tangible equity capital by its average total consolidated assets. The rule further describes what is included in tangible equity capital and average total consolidated assets. Qualifying banks may opt in and out of the CBLR framework at any time. While we are a qualifying community banking organization, we have not opted into the CBLR framework at this time. See below, for further discussion of the Economic Growth Act.

The Dodd-Frank Wall Street Reform and Consumer Protection Act and the Economic Growth, Regulatory Relief, and Consumer Protection Act

The Dodd-Frank Act, a landmark financial reform bill comprised of voluminous new rules and restrictions on bank operations, included provisions aimed at preventing a repeat of the 2008 financial crisis and a new process for winding down failing, systemically important institutions in a manner as close to a controlled bankruptcy as possible. Among other things, the Dodd-Frank Act established new government oversight responsibilities, enhanced capital

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adequacy requirements for certain institutions, established consumer protection laws and regulations, and placed limitations on certain banking activities.

In an attempt to reduce the regulatory burden on U.S. companies, including financial institutions, in May 2018, the Presidential Administration signed the Economic Growth Act, which repealed or modified certain provisions of the Dodd-Frank Act and eased regulations on all but the largest banks. The Economic Growth Act’s highlights included improving consumer access to mortgage credit, added certain protections for consumers, included veterans and active duty military personnel, expanded credit freezes and created an identity theft protection database.

Notice and Approval Requirements Related to Control

Banking laws impose notice, approval and ongoing regulatory requirements on any shareholder or other party that seeks to acquire direct or indirect "control" of an FDIC-insured depository institution. These laws include the BHCA and the Change in Bank Control Act. Among other things, these laws require regulatory filings by a shareholder or other party that seeks to acquire direct or indirect "control" of an FDIC-insured depository institution or bank holding company. The determination whether an investor "controls" a depository institution is based on all of the facts and circumstances surrounding the investment. As a general matter, a party is deemed to control a depository institution or other company if the party owns or controls 25% or more of any class of voting stock. Subject to rebuttal, a party may be presumed to control a depository institution or other company if the investor owns or controls 10% or more of any class of voting stock. Ownership by family members, affiliated parties, or parties acting in concert, is typically aggregated for these purposes. If a party's ownership of the Company were to exceed certain thresholds, the investor could be deemed to "control" the Company for regulatory purposes. This could subject the investor to regulatory filings or other regulatory consequences.

In addition, except under limited circumstances, bank holding companies are prohibited from acquiring, without prior approval: 1) control of any other bank or bank holding company or all or substantially all the assets thereof; or 2) more than 5% of the voting shares of a bank or bank holding company that is not already a subsidiary.

Incentive Compensation

The Dodd-Frank Act required federal bank regulators and the Securities and Exchange Commission ("SEC") to establish joint regulations or guidelines prohibiting incentive-based payment arrangements that encourage inappropriate risks by providing an executive officer, employee, director or principal stockholder with excessive compensation, fees, or benefits or that could lead to material financial loss to the entity. These regulations apply to institutions having at least $1 billion in total assets. In addition, regulators must establish regulations or guidelines requiring enhanced disclosure to regulators of incentive-based compensation arrangements. The agencies have not finalized regulations proposed in April 2016. If adopted, the proposed regulations could place limits on the manner in which we structure our executive compensation.

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

Available Information

On our Internet web site, www.bankofmarin.com, we post the following filings as soon as reasonably practical after they are filed with or furnished to the Securities and Exchange Commission: Annual Report to Shareholders, Form 10-K, Proxy Statement for the Annual Meeting of Shareholders, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities and Exchange Act of 1934. All such materials on our website are available free of charge. This website address is for information only and is not intended to be an active link, or to incorporate any website information into this document. In addition, copies of our filings are available by requesting them in writing or by phone from:

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Corporate Secretary

Bank of Marin Bancorp

504 Redwood Boulevard, Suite 100

Novato, CA 94947

415-763-4523

These materials are also available at the SEC’s internet website (https://www.sec.gov).

ITEM 1A. RISK FACTORS

We assume and manage a certain degree of risk in order to conduct our business. The material risks and uncertainties that management believes may affect our business are listed below and in ITEM 7A, Quantitative and Qualitative Disclosure about Market Risk. The list is not exhaustive; additional risks and uncertainties that management is not aware of, or focused on, or currently deems immaterial may also impair business operations. If any of the following risks, or risks that have not been identified, actually occur, our financial condition, results of operations, and stock trading price could be materially and adversely affected. We manage these risks by promoting sound corporate governance practices, which include but are not limited to, establishing policies and internal controls, and implementing internal review processes. Before making an investment decision, investors should carefully consider the risks, together with all of the other information included or incorporated by reference in this Annual Report on Form 10-K and our other filings with the SEC. This report is qualified in its entirety by these risk factors.

Strategic, Financial, and Reputational Risks

Our Business, Results of Operations, and Financial Condition Have Been Adversely Affected by the Ongoing COVID-19 Pandemic

The COVID-19 pandemic has caused significant economic and business disruptions. The extent to which the pandemic impacts our business, results of operations and financial condition depends on future developments, which are uncertain and are difficult to predict and measure, including, but not limited to, the duration and spread of new variants, actions to contain the virus including the timely deployment of effective vaccination and other government-initiated actions or mandates, and how quickly and to what extent normal economic and operating conditions resume, particularly in California. As a result, we are subject to the following risks, which could have a material effect on our business, financial condition, results of operations, capital position and liquidity:

•The COVID-19 pandemic has negatively impacted the global economy, disrupted global supply chains, created significant volatility and disrupted financial markets and equity market valuations. These factors could lead to increases in loan delinquencies, problem assets and foreclosures, and closures of businesses, which may increase loan losses.

•Commercial real estate ("CRE") loan demand and credit risk could be adversely affected longer-term by the pandemic due to structural changes relating to remote work trends, continued migration of the workforce outside of metropolitan areas, and business closures. These trends could increase vacancy rates and reduce commercial real estate values.

•Demand for our products and services, including deposits, may decline making it increasingly difficult to grow assets and income.

•The low interest rate environment in 2020 and 2021 has resulted in decreases in yields on our interest-earning assets that exceed the decline in our cost of interest-bearing liabilities and has compressed our net interest margin.

•Our business operations may be disrupted if significant portions of our workforce are unable to work effectively because of illness, quarantines, government actions, and other restrictions in connection with the pandemic.

•Our borrowers' payment performance may be worse than anticipated, as pandemic-related payment deferrals expire. While approximately 94% of our payment relief loans have resumed normal payments, we have no assurance that these borrowers will not require additional payment relief in the future due to the continued impact of the pandemic.

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Growth Strategy or Potential Mergers and Acquisitions May Produce Unfavorable Outcomes

We seek to expand our franchise safely and consistently. A successful growth strategy requires us to manage multiple aspects of the business simultaneously, such as following adequate loan underwriting standards, balancing loan and deposit growth without compressing our net interest margin, managing interest rate risk, maintaining sufficient capital, and recruiting, training and retaining qualified professionals. Our strategic plan also includes merger and acquisition opportunities, such as the 2021 merger with American River Bankshares, that either enhance our market presence or have potential for improved profitability through financial management, economies of scale or expanded services. We may incur significant acquisition related expenses either during the due diligence phase of acquisition targets or during integration of the acquirees. These expenses have and may continue to negatively impact our earnings prior to realizing the benefits of acquisitions. We may also be exposed to difficulties in combining the operations of acquired institutions into our own operations, which may prevent us from achieving the expected benefits from our acquisition activities. Our earnings, financial condition and prospects after the merger may affect our stock price and will depend in part on our ability to integrate the operations and management of the acquired institution while continuing to implement other aspects of our business plan. Inherent uncertainties exist in integrating the operations of an acquired institution and there is no assurance that we will be able to do so successfully. Among the issues that we could face are:

•unexpected problems with operations, personnel, technology or credit;

•loss of customers and employees of the acquiree;

•difficulty in working with the acquiree's employees and customers;

•the assimilation and integration of the acquiree's operations, culture and personnel;

•instituting and maintaining uniform standards, controls, procedures and policies; and

•litigation risk or obligations not discovered during due diligence.

Undiscovered factors as a result of an acquisition could bring liabilities against us, our management and the management of the institutions we acquire. These factors could contribute to our not achieving the expected benefits from our acquisitions within desired time frames, if at all. Further, although we generally anticipate cost savings from acquisitions, we may not be able to fully realize those savings. Any cost savings may be offset by losses in revenues or other charges to earnings.

Competition with Other Financial Institutions to Attract and Retain Banking Customers

We are facing significant competition for customers from other banks and financial institutions located in the markets that we serve. We compete with commercial banks, savings institutions, credit unions, non-bank financial services companies, including financial technology firms, and other financial institutions operating within or near our service areas. Some of our non-bank competitors and peer-to-peer lenders may not be subject to the same extensive regulations as we are, giving them greater flexibility in competing for business. We anticipate intense competition will continue for the coming year due to the consolidation of many financial institutions and more changes in legislation, regulation and technology. National and regional banks much larger than our size have entered our market through acquisitions and they may be able to benefit from economies of scale through their wider branch networks, more prominent national advertising campaigns, lower cost of borrowing, capital market access and sophisticated technology infrastructures. Further, intense competition for creditworthy borrowers could lead to pressure for loan rate concessions and affect our ability to generate profitable loans.

Going forward, we may see continued competition in the industry as competitors seek to expand market share in our core markets. Further, our customers may withdraw deposits to pursue alternative investment opportunities in the equity market. Technology and other changes have made it more convenient for bank customers to transfer funds into alternative investments or other deposit platforms such as online virtual banks and non-bank service providers. Efforts and initiatives we may undertake to retain and increase deposits, including deposit pricing, can increase our costs. Based on our current strong liquidity position, our adjustment to deposit pricing has lagged the market in a rising interest rate environment. If our customers move money into higher yielding deposits or alternative investments, we may lose a relatively inexpensive source of funds, thus increasing our funding costs through more expensive wholesale funding sources, such as federal funds or FHLB borrowings.

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We May Not Be Able to Attract and Retain Key Employees

Our success depends in large part on our ability to attract qualified personnel and to retain key employees, as well as the prompt replacement of retiring executives. The loss of key personnel and/or our inability to secure qualified candidates to replace retiring executives could have an unfavorable effect on our business due to the required skills and knowledge of our market and years of industry experience.

Bancorp Relies on Dividends from the Bank to Pay Cash Dividends to its Shareholders as Well as to Meet Other Financial Obligations

Bancorp is a separate legal entity from its subsidiary, the Bank. Bancorp receives substantially all of its cash stream from the Bank in the form of dividends, which is Bancorp's principal source of funds to pay cash dividends to Bancorp's common shareholders, repurchase shares, and cover operational expenses of the holding company. Various federal and state laws and regulations limit the amount of dividends that the Bank may pay to Bancorp. In the event that the Bank is unable to pay dividends to Bancorp, Bancorp may not be able to pay dividends to its shareholders. As a result, it could have an adverse effect on Bancorp's stock price and investment value.

Federal law would prohibit capital distributions from the Bank, with limited exceptions, if the Bank were categorized as "undercapitalized" under applicable Federal Reserve or FDIC regulations. In addition, as a California bank, Bank of Marin is subject to state law restrictions on the payment of dividends. For further information on the distribution limit from the Bank to Bancorp, see the section captioned “Bank Regulation” in ITEM 1 above and “Dividends” in Note 8 to the Consolidated Financial Statements in ITEM 8 of this report.

The Value of Goodwill and Other Intangible Assets May Decline in the Future

As of December 31, 2021, we had goodwill totaling $72.8 million and a core deposit intangible asset totaling $6.6 million from business acquisitions. A significant decline in expected future cash flows, a significant adverse change in the business climate, or a significant and sustained decline in the price of our common stock could necessitate taking charges in the future related to the impairment of goodwill or other intangible assets. If we were to conclude that a future write-down of goodwill or other intangible assets is necessary, we would record the appropriate charge, which could have a material adverse effect on our business, financial condition and results of operations.

We May Take Tax Filing Positions or Follow Tax Strategies That May Be Subject to Challenge

We provide for current and deferred tax provision in our consolidated financial statements based on our results of operations, business activities and business combinations, legal structure and federal and state legislation and regulations. We may take filing positions or follow tax strategies that are subject to interpretation of tax statutes. Our net income may be reduced if a federal, state or local authority were to assess charges for taxes that have not been provided for in our consolidated financial statements. Taxing authorities could change applicable tax laws and interpretations, challenge filing positions or assess new taxes and interest charges. If taxing authorities take any of these actions, our business, results of operations or financial condition could be significantly affected.

Credit Risks

We are Subject to Significant Credit Risk and Loan Losses May Exceed Our Allowance for Credit Losses in the Future

The operation of our business requires us to manage credit risk. As a lender, we are exposed to the risk that our borrowers will be unable to repay their loans according to their terms, and that the collateral securing repayment of their loans, if any, may not be sufficient to ensure repayment. In addition, there are risks inherent in making any loan, including risks with respect to the period of time over which the loan may be repaid, risks relating to proper loan underwriting, risks resulting from changes in economic and industry conditions and risks inherent in dealing with individual borrowers. In order to successfully manage credit risk, we must, among other things, maintain disciplined and prudent underwriting standards and ensure that our bankers follow those standards. The weakening of these standards for any reason, such as an attempt to attract higher yielding loans, a lack of discipline or diligence by our employees in underwriting and monitoring loans, the inability of our employees to adequately adapt policies and procedures to changes in economic or any other conditions affecting borrowers and the quality of our

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loan portfolio, may result in loan defaults, foreclosures and additional charge-offs and may necessitate that we significantly increase our allowance for credit losses on loans, each of which could adversely affect our net income. As a result, any inability to successfully manage credit risk could have a material adverse effect on our business, financial condition or results of operations.

We maintain allowances for credit losses on loans and unfunded loan commitments that represent management's best estimate of expected credit losses over the contractual lives of our loans under the current expected credit loss method. The level of the allowance reflects management's continuous evaluation of specific credit risks, loan loss experience, current loan portfolio quality and present and forecasted economic, political and regulatory conditions. The determination of the appropriate level of the allowances inherently involves a high degree of subjectivity and requires us to make significant estimates of current credit risks and trends and future economic forecasts, all of which may undergo material changes. Inaccurate assumptions in appraisals or an inappropriate choice of the valuation techniques may lead to an inadequate level of specific reserve or charge-offs.

The Small to Medium-sized Businesses that we Lend to may have Fewer Resources to Weather Adverse Economic and Other Developments, which may Impair a Borrower's Ability to Repay a Loan

We focus our business development and marketing strategy primarily on small to medium-sized businesses. Small to medium-sized businesses frequently have smaller market shares than their competition, may be more vulnerable to economic downturns, often need substantial additional capital to expand or compete and may experience substantial volatility in operating results, any of which may impair a borrower's ability to repay a loan. In addition, the success of a small and medium-sized business often depends on the management talents and efforts of one or two people or a small group of people, and the death, disability or resignation of one or more of these people could adversely affect the business and its ability to repay its loan. If general economic conditions negatively affect the California markets in which we operate and small to medium-sized businesses are adversely affected or our borrowers are otherwise affected by adverse business developments, our business, financial condition and results of operations may be negatively affected.

Negative Conditions Affecting Real Estate May Harm Our Business and Our Commercial Real Estate Concentration May Heighten Such Risk

Concentration of our lending activities in the California real estate sector could negatively affect our results of operations if adverse changes in our lending area occur. We do not offer traditional first mortgages, nor have sub-prime or Alt-A residential loans or significant amounts of securities backed by such loans in the portfolios. As of December 31, 2021, approximately 86% of our loans were secured by real estate, with CRE comprising 75% and residential real estate the remaining 25%. Real estate valuations are influenced by demand, and demand is driven by economic factors such as employment rates and interest rates.

Loans secured by CRE include those secured by office buildings, owner-user office/warehouses, mixed-use commercial and retail properties. There can be no assurance that properties securing our loans will generate sufficient cash flows to allow borrowers to make full and timely loan payments to us. During the COVID-19 pandemic, many small businesses closed and may not reopen. Some pandemic-driven activity, such as shifts from in-person to online shopping and from office-based to remote work, may prove to be permanent. These shifts could impact the demand for CRE and also put persistent downward pressure on CRE valuations.

Rising CRE lending concentrations may expose institutions to unanticipated earnings and capital volatility in the event of adverse changes in the CRE market. Concentration risk exists when financial institutions deploy too many assets to any one industry or segment. Concentration stemming from commercial real estate is one area of regulatory concern. The CRE Concentration Guidance provides supervisory criteria, including the following numerical indicators, to assist bank examiners in identifying banks with potentially significant commercial real estate loan concentrations that may warrant greater supervisory scrutiny: (i) commercial real estate loans exceeding 300% of capital and increasing 50% or more in the preceding three years; or (ii) construction and land development loans exceeding 100% of capital. The CRE Concentration Guidance does not limit banks’ levels of commercial real estate lending activities, but rather guides institutions in developing risk management practices and levels of capital that are commensurate with the level and nature of their commercial real estate concentrations. As of December 31, 2021 and 2020, using regulatory definitions in the CRE Concentration Guidance, our CRE loans represented 332% and 314%, respectively, of our total risk-based capital. We are actively working to manage our CRE concentration and we have discussed the CRE Concentration Guidance with the regulatory agencies and believe that our

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underwriting policies, management information systems, independent credit administration process, and monitoring of real estate loan concentrations are currently sufficient to address the CRE Concentration Guidance.

Accounting Estimates and Risk Management Processes Rely on Analytical and Forecasting Models

The processes we use to estimate expected credit losses on loans and investment securities, and to measure the fair value of financial instruments, as well as the processes used to estimate the effects of changing interest rates and other market measures on our financial condition and results of operations, depends upon the use of analytical and forecasting models. These models reflect assumptions that may not be accurate, particularly in times of market volatility or other unforeseen circumstances. Even if these assumptions are adequate, the models may prove to be inadequate or inaccurate because of other flaws in their design or their implementation. If the models we use for interest rate risk and asset-liability management are inadequate, we may incur increased or unexpected losses upon changes in market interest rates or other market factors. If the models we use for determining our expected credit losses on loans and investment securities are inadequate, the allowance for credit losses may not be sufficient to support future charge-offs. If the models we use to measure the fair value of financial instruments are inadequate, the fair value of such financial instruments may fluctuate unexpectedly or may not accurately reflect what we could realize upon sale or settlement of such financial instruments. Any such failure in our analytical or forecasting models could have a material adverse effect on our business, financial condition and results of operations.

Investment Securities May Lose Value due to Credit Quality of the Issuers

We invest in significant portions of debt securities issued by government-sponsored enterprises ("GSE"), such as Federal Home Loan Bank ("FHLB"), Federal National Mortgage Association (“FNMA”), and Federal Home Loan Mortgage Corporation ("FHLMC"). We also hold mortgage-backed securities (“MBS”) issued by FNMA and FHLMC, both of which have been under U.S. government conservatorship since 2008. While we consider FNMA and FHLMC securities to have low credit risk as they carry the explicit backing of the U.S. government due to the conservatorship, they are not direct obligations of the U.S. government. The fair value of our securities issued or guaranteed by these two GSE entities may be negatively impacted if the U.S. government ceases to provide support to the conservatorship or phases out its current practice of purchasing treasury and agency mortgage-backed securities. GSE debt is sponsored but not guaranteed by the federal government and carries implicit backing, whereas government agencies such as Government National Mortgage Association ("GNMA") are divisions of the government whose securities are backed by the full faith and credit of the U.S. government.

Although Congress has taken steps to improve regulation and consumer protection related to the housing finance system (e.g., Dodd-Frank Act), FNMA and FHLMC have entered their 14th year of U.S. government conservatorship via the Federal Housing Finance Agency (the "FHFA"). While proposals to end the conservatorship have considered solutions such as an initial public offering, at the date of this report, its future and ultimate impact on the financial markets and our investments in GSEs are uncertain.

While we generally seek to minimize our exposure by strategically diversifying our credit exposure to obligations of issuers in various geographic locations throughout California and the U.S., investing in investment grade securities and actively monitoring the credit worthiness of the issuers and/or credit guarantee providers, there is no guarantee that the issuers will remain financially sound or continue their payments on these debentures.

Market, Interest Rate, and Liquidity Risks

Earnings are Significantly Influenced by General Business and Economic Conditions

Our success depends, to a certain extent, on local, national and global economic and political conditions. Unlike larger national or other regional banks that are more geographically diversified, we provide banking and financial services to customers primarily in Northern California with particular focus on the local markets in the San Francisco Bay and Greater Sacramento regions. The local economic conditions in these areas have a significant impact on the demand for our products and services as well as the ability of our customers to repay loans, the value of the collateral securing loans and the stability of our deposits as our primary funding source. Economic pressure on consumers and uncertainty regarding the economy and local business climate may result in changes in consumer and business spending, borrowing and saving habits, which may affect the demand for loans and other products

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and services we offer. Further, loan defaults that adversely affect our earnings correlate highly with deteriorating economic conditions (such as the California unemployment rate and California gross domestic product), which impact our borrowers' creditworthiness. In addition, health epidemics or pandemics (or expectations about them) such as the novel coronavirus (aka "COVID-19"), international trade disputes, inflation risks, oil price volatility, the level of U.S. debt and global economic conditions could destabilize financial markets in which we operate. Lastly, actions of the Federal Open Market Committee ("FOMC") of the Federal Reserve could cause financial market volatility, which will affect the pricing of our loan and deposit products.

Interest Rate Risk is Inherent in Our Business

Our earnings are largely dependent upon our net interest income, which is the difference between interest income earned on interest-earning assets, such as loans and securities, and interest expense paid on interest-bearing liabilities, such as deposits and borrowed funds. Interest rates are sensitive to many factors outside of our control, including general economic conditions and the policies of various governmental and regulatory agencies and, in particular, the FOMC, which regulates the supply of money and credit in the United States. Changes in monetary policy, including changes in interest rates, can influence not only the interest we receive on loans and securities and interest we pay on deposits and borrowings, but can also affect (i) our ability to originate loans and obtain deposits, (ii) the fair value of our financial assets and liabilities, and (iii) the duration of our securities and loan portfolios. Our portfolio of loans and securities will generally decline in value if market interest rates increase, and increase in value if market interest rates decline. In addition, our loans and callable mortgage-backed securities are also subject to prepayment risk when interest rates fall, and the borrowers' credit risk may increase in rising rate or recessionary environments. Factors such as inflation, productivity, oil prices, unemployment rates, and global demand play a role in the FOMC's consideration of future rate adjustments. In March 2020, in response to the evolving risks to economic activity posed by the COVID-19 pandemic, the FOMC made two emergency cuts to the federal funds rate totaling 150 basis points to a current target range of 0.0% to 0.25%. This has put downward pressure on our asset yields and net interest margin. Our net interest income is vulnerable to low interest rates and will benefit if prevailing market rates increase. See the Net Interest Income section of Management's Discussion and Analysis of Financial Condition and Results of Operations in ITEM 7 and Quantitative and Qualitative Disclosures about Market Risk in ITEM 7A of this report for further discussion related to management of interest rate risk.

A Lack of Liquidity could Adversely Affect our Operations and Jeopardize our Business, Financial Condition and Results of Operations

Liquidity is essential to our business. We rely on our ability to generate deposits and effectively manage the repayment and maturity schedules of our loans and investment securities, respectively, to ensure that we have adequate liquidity to fund our operations. An inability to raise funds through deposits, borrowings, securities sales, Federal Home Loan Bank advances, the sale of loans and other sources could have a substantial negative effect on our liquidity. Our most important source of funding consists of deposits. Deposit balances can decrease when customers perceive alternative investments provide a better risk/return trade-off. If customers move money out of bank deposits and into other investments, then we would lose a relatively low-cost source of funds, increasing our funding costs and reducing our net interest income and net income.

Other primary sources of funds consist of cash flows from operations, investment maturities and sales, loan repayments, and proceeds from the issuance and sale of any equity and debt securities to investors. Additional liquidity is provided by the ability to borrow from the Federal Reserve Bank of San Francisco and the Federal Home Loan Bank and our ability to raise brokered deposits. We also may borrow funds from third-party lenders, such as other financial institutions. Our access to funding sources in amounts adequate to finance or capitalize our activities, or on terms that are acceptable to us, could be impaired by factors that affect us directly or the bank or non-bank financial services industries or the economy in general, such as disruptions in the financial markets or negative views and expectations about the prospects for the bank or non-bank financial services industries.

Based on experience, we believe that our deposit accounts are relatively stable sources of funds. If we increase interest rates paid to retain deposits, our earnings may be adversely affected, which could have an adverse effect on our business, financial condition and results of operations.

Any decline in available funding could adversely affect our ability to originate loans, invest in securities, meet our expenses, and pay dividends to our shareholders or fulfill obligations such as repaying our borrowings or meeting

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deposit withdrawal demands, any of which could have a material adverse impact on our liquidity, business, financial condition and results of operations.

Activities of Our Large Borrowers and Depositors May Cause Unexpected Volatilities in Our Loan and Deposit Balances, as well as Net Interest Margin

Loans originated at higher interest rates may be paid off and replaced by new loans with lower interest rates, causing downward pressure on our net interest margin. In addition, our top ten depositor relationships accounted for approximately 11% and 10% of our total deposit balances at December 31, 2021 and 2020, respectively. Since the start of the pandemic in 2020, the banking industry in general has experienced abundant liquidity driven by pandemic-related government programs such as PPP and consumer stimulus checks as well as elevated savings by depositors. This trend may reverse as the economy recovers. In addition, the business models and cash cycles of some of our large commercial depositors may also cause short-term volatility in their deposit balances held with us. As our customers' businesses grow, the dollar value of their daily activities may also grow leading to larger fluctuations in daily balances. Any long-term decline in deposit funding would adversely affect our liquidity. For additional information on our management of deposit volatility, refer to the Liquidity section of ITEM 7, Management's Discussion and Analysis, of this report.

Unexpected Early Termination of Interest Rate Swap Agreements May Affect Earnings

We have entered into interest-rate swap agreements, primarily as an asset/liability risk management tool, in order to mitigate the interest rate risk that causes fluctuations in the fair value of specified long-term fixed-rate loans or firm commitments to originate long-term fixed rate loans. In the event of default by the borrowers on our hedged loans, we may have to terminate these designated interest-rate swap agreements early, resulting in market value losses that could negatively affect our earnings.

The Trading Volume of Bancorp's Common Stock May Be Less than That of Other, Larger Financial Services Companies

Our common stock is listed on the Nasdaq Capital Market exchange. Our trading volume is less than that of nationwide or larger regional financial institutions. A public trading market having the desired characteristics of depth, liquidity and orderliness depends on the presence of willing buyers and sellers of common stock at any given time. This presence depends on the individual decisions of investors and general economic and market conditions over which we have no control. Given the low trading volume of our common stock, significant trades of our stock in a given time, or the expectations of these trades, could cause volatility in the stock price.

We are Subject to Uncertainty from the Transition of London Interbank Offered Rate ('LIBOR") as a Reference Rate

LIBOR has been one of the most widely used global interest rate benchmark deeply embedded in global financial products. The long-term viability of LIBOR has been undermined due to cases of rate manipulation, low volumes for underlying interbank transactions and the reluctance of panel banks to submit quotes used to calculate LIBOR. As a result, the Financial Conduct Authority of the United Kingdom (the “FCA”) announced that the most commonly used U.S. dollar ("USD") LIBOR rates will either cease to be published or no longer be deemed representative after June 30, 2023. 1-week and 2-month USD LIBOR ceased to be published as of December 31, 2021. The Alternative Reference Rates Committee (“ARRC”), a steering committee comprised of U.S. financial market participants selected by the Federal Reserve Bank of New York, published recommended fall-back language for LIBOR-linked financial instruments and recommended alternatives for certain LIBOR rates (e.g., Secured Overnight Financing Rate (“SOFR”), a broad measure of the cost of overnight borrowings collateralized by Treasury securities, for USD LIBOR). The federal banking agencies have issued guidance requesting banking organizations cease using LIBOR as a reference rate in new contracts by December 31, 2021.

As of December 31, 2021, we had twenty-five investment securities with book values totaling $43.2 million, seven loans totaling $11.5 million, and four interest rate swap contracts with notional values of $13.0 million indexed to LIBOR. Almost all of our LIBOR-indexed investment securities were issued by GSEs who are members of ARRC and have transition strategies and timelines for their legacy LIBOR-indexed investment products, including fall-back rates tied to 30-day average SOFR or Term SOFR. We discontinued originating LIBOR-based loans effective

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December 31, 2021. Loans currently indexed to LIBOR either have contractual fall-back rates or will be negotiated using replacement indices such as SOFR or Bloomberg Short-Term Bank Yield Index ("BSBY"), a benchmark developed by Bloomberg Professional Services. In addition, our interest rate swap agreements can either be subject to the fall-back index rate stipulated by the ISDA protocol or modified to other reference rates such as Prime or SOFR as mutually agreed by us and our counterparty.

While management has identified financial instruments indexed to LIBOR and evaluated contracts and index alternatives, we cannot predict any favorable or unfavorable effects the chosen alternative index may have on financial instruments that are currently indexed to LIBOR after its termination date.

Operational Risks

Risks Associated with Cybersecurity Could Negatively Affect Our Earnings and Reputation

Our business requires the secure management of sensitive client and bank information. We work diligently to implement security measures that intend to make our communications and information systems safe to conduct business. Cyber threats such as social engineering, ransomware, and phishing emails are more prevalent now than ever before. These incidents include intentional and unintentional events that may present threats designed to disrupt operations, corrupt data, release sensitive information or cause denial-of-service attacks. A cybersecurity breach of systems operated by the Bank, merchants, vendors, customers, or externally publicized breaches of other financial institutions may significantly harm our reputation, result in a loss of customer business, subject us to regulatory scrutiny, or expose us to civil litigation and financial liability. While we have systems and procedures designed to prevent security breaches, we cannot be certain that advances in criminal capabilities, physical system or network break-ins or inappropriate access will not compromise or breach the technology protecting our networks or proprietary client information. If a material security breach were to occur, the Bank has policies and procedures in place to ensure timely disclosure.

The Financial Services Industry is Undergoing Rapid Technological Changes and, As a Result, We Have a Continuing Need to Stay Current with Those Changes to Compete Effectively and Increase Our Efficiencies. We May Not Have the Resources to Implement New Technology to Stay Current with These Changes

The financial services industry is undergoing technological changes with frequent introductions of new technology-driven products and services. In addition to providing better client service, the effective use of technology increases efficiency and reduces operational costs. Our future success will depend in part upon our ability to use technology to provide products and services that will satisfy client demands securely and cost-effectively. In connection with implementing new technology enhancements and/or products, we may experience operational challenges (e.g. human error, system error, incompatibility) which could result in us not fully realizing the anticipated benefits from such new technology or require us to incur significant costs to remedy any such challenges in a timely manner.

Severe Weather, Natural Disasters or Other Climate Change Related Matters Could Significantly Affect Our Business

Our primary market is located in both earthquake and wildfire-prone zones in Northern California, which is also subject to other weather or disasters, such as severe rainstorms, drought or flood. These events have interrupted our business operations unexpectedly (e.g., PG&E power shutoff's in the North Bay and Sacramento Region) at times. Climate-related physical changes and hazards could also pose credit risks for us. For example, our borrowers may have collateral properties or operations located in areas at risk of wildfires, or coastal areas at risk to rising sea levels and erosion, or subject to the risk of drought in California. The properties pledged as collateral on our loan portfolio could also be damaged by tsunamis, landslides, floods, earthquakes or wildfires and thereby the recoverability of loans could be impaired. A number of factors can affect credit losses, including the extent of damage to the collateral, the extent of damage not covered by insurance, the extent to which unemployment and other economic conditions caused by the natural disaster adversely affect the ability of borrowers to repay their loans, and the cost of collection and foreclosure to us. Additionally, there could be increased insurance premiums and deductibles, or a decrease in the availability of coverage, due to severe weather-related losses. The ultimate outcome on our business of a natural disaster, whether or not caused by climate change, is difficult to predict.

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We Rely on Third-Party Vendors for Important Aspects of Our Operation

We depend on the accuracy and completeness of information and systems provided by certain key vendors, including but not limited to data processing, payroll processing, technology support, investment safekeeping and accounting. For example, we outsource core processing to Fidelity Information Services ("FIS") and wire processing to Finastra, which are leading financial services solution providers that allow us access to competitive technology offerings without having to invest in their development. Our ability to operate, as well as our financial condition and results of operations, could be negatively affected in the event of an interruption of an information system, an undetected error, a cyber-breach, or in the event of a natural disaster whereby certain vendors are unable to maintain business continuity.

Regulatory and Compliance Risks

Banks and Bank Holding Companies are Subject to Extensive Government Regulation and Supervision

Bancorp and the Bank are subject to extensive federal and state governmental supervision, regulation and control. Holding company regulations affect the range of activities in which Bancorp is engaged. Banking regulations affect the Bank's lending practices, capital structure, investment practices, dividend policy, and compliance costs among other things. Compliance risk is the current and prospective risk to earnings or capital arising from violations of, or non-conformance with, laws, rules, regulations, prescribed practices, internal policies and procedures, or ethical standards set forth by regulators. Compliance risk also arises in situations where the laws or rules governing certain bank products or activities of our clients may be ambiguous or untested. This risk exposes Bancorp and the Bank to potential fines, civil money penalties, payment of damages and the voiding of contracts. Compliance risk can lead to diminished reputation, reduced franchise value, limited business opportunities, reduced expansion potential and an inability to enforce contracts. The Bank manages these risks through its extensive compliance plan, policies and procedures. For further information on supervision and regulation, see the section captioned “SUPERVISION AND REGULATION” in ITEM 1 of this report.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None

ITEM 2. PROPERTIES

We lease our corporate headquarters building in Novato, California, which houses loan production, operations, Wealth Management & Trust and administration. We lease branch and office facilities within our primary market areas in the cities of Corte Madera, San Rafael, Novato, Sausalito, Mill Valley, Tiburon, Greenbrae, Petaluma, Santa Rosa, Healdsburg, Sonoma, Napa, San Francisco, Alameda, Oakland, Walnut Creek, San Mateo, Gold River, Jackson, Pioneer, Roseville, and Sacramento. For additional information on properties, Refer to Note 4, Bank Premises and Equipment, and Note 12, Commitment and Contingencies, in ITEM 8 of this report.

ITEM 3. LEGAL PROCEEDINGS

For information on litigation matters, see Note 12, Commitment and Contingencies, in ITEM 8 of this report.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

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PART II

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

Market Information and Holders

Bancorp's common stock trades on the Nasdaq Capital Market under the symbol BMRC. At February 28, 2022, 15,939,659 shares of Bancorp's common stock, no par value, were outstanding and held by approximately 2,900 holders of record and beneficial owners.

Five-Year Stock Price Performance Graph

The following graph, compiled by S&P Global Market Intelligence of New York, New York, shows a comparison of cumulative total shareholder return on our common stock during the five fiscal years ended December 31, 2021 compared to the Russell 2000 Stock index and the S&P Regional Banks Select Industry Index. The comparison assumes the investment of $100 in our common stock on December 31, 2016 and the reinvestment of all dividends. The graph represents past performance and does not indicate future performance. In addition, total return performance results vary depending on the length of the performance period.

Source: S&P Global Market Intelligence

1 The index comprises stocks in the S&P Total Market Index that are classified in the Global Industry Classification Standard regional banks sub-industry.

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Shareholder Rights Agreement

On July 6, 2017, Bancorp executed a shareholder rights agreement (“Rights Agreement”), which is designed to discourage takeovers that involve abusive tactics or do not provide fair value to shareholders. For further information, see Note 8 to the Consolidated Financial Statements, under the heading “Preferred Stock and Shareholder Rights Plan” in ITEM 8 of this report.

Securities Authorized for Issuance under Equity Compensation Plans

The following table summarizes information as of December 31, 2021, with respect to equity compensation plans.

1 Represents shares of common stock issuable upon exercise of outstanding options under the Bank of Marin Bancorp 2017 Equity Plan and 2007 Equity Plan.

2 Represents remaining shares of common stock available for future grants under the 2017 Equity Plan and the 2020 Director Stock Plan, excluding 315,744 shares to be issued upon exercise of outstanding options and 377,475 shares available to be issued under the Employee Stock Purchase Plan.

Purchases of Equity Securities by the Issuer and Affiliated Purchasers

On April 23, 2018, Bancorp announced that its Board of Directors approved a Share Repurchase Program under which Bancorp may repurchase up to $25.0 million of its outstanding common stock through May 1, 2019. Bancorp's Board of Directors subsequently extended the Share Repurchase Program through February 28, 2020. A new Share Repurchase Program was approved by the Board of Directors on January 24, 2020, which began on March 1, 2020 and allowed Bancorp to repurchase up to $25.0 million of its outstanding common stock and ended May 2021. On July 16, 2021, Bancorp Board of Directors approved a share repurchase program under which Bancorp could repurchase up to $25.0 million of its outstanding common stock through July 31, 2023. On October 22, 2021, Bancorp's Board of Directors approved an amendment to the current share repurchase program, which increased the total authorization from $25.0 million to $57.0 million and left the expiration date unchanged.

Shares repurchased pursuant to our common stock share repurchase programs during 2021, 2020 and 2019, were as follows.

The following table reflects purchases under the Share Repurchase Program for the months presented in 2021.

Period

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ITEM 6. [RESERVED]

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion of financial condition as of December 31, 2021 and 2020 and results of operations for each of the years in the three-year period ended December 31, 2021 should be read in conjunction with our consolidated financial statements and related notes thereto, included in Part II ITEM 8 of this report.

Forward-Looking Statements

The disclosures set forth in this item are qualified by important factors detailed in Part I captioned Forward-Looking Statements and ITEM 1A captioned Risk Factors of this report and other cautionary statements set forth elsewhere in the report.

Critical Accounting Estimates

Critical accounting estimates are those estimates made in accordance with generally accepted accounting principles that involve a significant level of estimation and uncertainty and have had or are reasonably likely to have a material impact on our financial condition and results of operations. We consider accounting estimates to be critical to our financial results if (i) the accounting estimate requires management to make assumptions about matters that are highly uncertain, (ii) management could have applied different assumptions during the reported period, and (iii) changes in the accounting estimate are reasonably likely to occur in the future and could have a material impact on our financial statements. Management has determined the following accounting estimates and related policies to be critical:

Allowance for Credit Losses on Loans and Unfunded Commitments

The allowance for credit losses on loans is a valuation account that is deducted from the amortized cost basis at the balance sheet date to present the net amount of loans expected to be collected. The allowance for losses on unfunded loan commitments is based on estimates of probability that these commitments will be drawn upon according to historical utilization experience, expected loss severity and loss rates as determined for pooled funded loans. The allowance for credit losses on unfunded commitments is a liability account included in interest payable and other liabilities. Management estimates these allowances quarterly using relevant available information, from internal and external sources, relating to past events, current conditions, and reasonable and supportable forecasts. Credit loss experience among the Bank and peer groups provides the basis for the estimation of expected credit losses.

The allowance for credit losses ("ACL") model utilizes a discounted cash flow ("DCF") method to measure the expected credit losses on loans collectively evaluated that are sub-segmented by loan pools with similar credit risk characteristics, which generally correspond to federal regulatory reporting codes. In addition, the DCF method incorporates assumptions for probability of default ("PD"), loss given default ("LGD"), and prepayments and curtailments over the contractual terms of the loans. Under the DCF method, the ACL reflects the difference between the amortized cost basis and the present value of the expected cash flows using the loan's effective rate.

Management considers whether adjustments to the quantitative portion of the ACL are needed for differences in segment-specific risk characteristics or to reflect the extent to which it expects current conditions and reasonable and supportable forecasts of economic conditions to differ from the conditions that existed during the historical period included in the development of PD and LGD.

Our allowance model is particularly sensitive to forecasted and seasonally-adjusted actual California unemployment rates, which decreased to 6.5% at December 31, 2021 from 9.3% at December 31, 2020. The ACL model incorporates a one-year forecast. For periods beyond the forecast horizon the economic factors revert to historical averages on a straight-line basis over a one-year period. We performed a sensitivity analysis as of December 31, 2021 and determined that a 1% change (e.g., 5.5% to 6.5%) in the forecasted quarterly unemployment rates over the next four quarters resulted in an 8% change to our allowance for credit losses on loans. This impact does not consider other assumption changes to either the quantitative factors, such as probability of default, loss given

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default, loan mix or cash flows, prepayment/curtailment rates, and individually analyzed loans, or qualitative factors as discussed in Note 1 - Summary of Significant Accounting Policies. Additionally, because current economic conditions and forecasts can change, as future events are inherently difficult to predict, the estimated credit losses on loans and unfunded commitments could change significantly.

While we believe we use the best information available to determine the allowance for credit losses, our results of operations could be significantly affected if circumstances differ substantially from the assumptions used in determining the allowance. For information regarding critical estimates related to our allowance for credit losses methodology, the provision for credit losses, and risks to asset quality and lending activity, see ITEM 1A - Risk Factors, the Allowance for Credit Losses section in ITEM 7 - Management's Discussion and Analysis of Financial Condition and Results of Operations,

Income Taxes

We are subject to the income tax laws of the U.S., its states, and the municipalities in which we operate. These tax laws are complex and subject to different interpretations by us and the government taxing authorities. We review our provision for income tax expense monthly and calculate the carrying value of deferred tax assets and liabilities quarterly. In establishing a provision for income tax expense, we make judgments and interpretations about the application of these inherently complex tax laws. In addition, our estimates include making judgements about when future items will affect taxable income. Although management believes that the judgments and estimates used are reasonable, actual results could differ and we may be exposed to losses or gains that could be material. For further information on our tax assets and liabilities, and related provision for income taxes, see Note 1 - Summary of Significant Accounting Policies and Note 11 - Income Taxes in ITEM 8 - Financial Statements and Supplementary Data of this Form 10-K.

Fair Value Measurements

We use fair value measurements to record certain financial instruments and to determine fair value disclosures. Available-for-sale securities and interest rate swap agreements are financial instruments recorded at fair value on a recurring basis. Additionally, we record at fair value other financial assets on a nonrecurring basis such as collateral dependent loans and other real estate owned. These nonrecurring fair value adjustments typically involve write-downs of, or specific reserves against, individual assets. We group our assets and liabilities that are measured at fair value into three levels within the fair value hierarchy, based on the markets in which the assets and liabilities are traded and the reliability of the assumptions used to determine fair value. The classification of assets and liabilities within the hierarchy is based on whether the inputs to the valuation methodology used in the measurement are observable or unobservable. Observable inputs reflect market-driven or market-based information obtained from independent sources, while unobservable inputs reflect our estimates about market data. The degree of management judgment involved in determining the fair value of a financial instrument is dependent upon the availability of quoted market prices or observable market data. For financial instruments that trade actively and have quoted market prices or observable market data, there is minimal subjectivity involved in measuring fair value. When observable market prices and data are not fully available, management judgment is necessary to estimate fair value. In addition, changes in the market conditions may reduce the availability of quoted prices or observable data. Therefore, when market data is not available, we use valuation techniques that require more management judgment to estimate the appropriate fair value measurement. Fair value is discussed further in Note 1 - Summary of Significant Accounting Policies and Note 9 - Fair Value of Assets and Liabilities in ITEM 8 - Financial Statements and Supplementary Data of this Form 10-K.

Business Combinations

Business combinations are accounted for using the acquisition method of accounting where the assets and liabilities of the acquired entities have been recorded at their estimated fair values at the date of acquisition. Goodwill represents the excess of the purchase price over the fair value of net assets acquired. The purchase price allocation process requires significant judgment in the estimation of the fair values of the assets acquired and the liabilities assumed. Management may obtain third-party valuations such as appraisals or discounted cash flow analyses, or we may derive fair values internally using techniques as discussed in Fair Value Measurements above. Management assesses qualifications of third-party valuation specialists, reviews assumptions applied and takes responsibility for the results of fair value estimates. Merger-related expenses include costs directly related to

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merger activity such as legal and professional fees, system consolidation and conversion costs, and compensation costs associated with employee severance and retention incentives. We account for merger-related costs as expenses in the periods in which the costs are incurred and the services received. Accounting policies and estimates are discussed further in Note 1 - Summary of Significant Accounting Policies and Note 18 - Merger in ITEM 8 - Financial Statements and Supplementary Data of this Form 10-K.

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RESULTS OF OPERATIONS

Financial Highlights

The following are highlights of our financial condition and results of operations. The data was derived from the audited consolidated financial statements of Bank of Marin Bancorp.

At December 31,

(dollars in thousands, except per share data) 2021 2020

Selected financial condition data:

Borrowings and other obligations $ 419 $ 58

Subordinated debenture $ — $ 2,777

Asset quality ratios:

Allowance for credit losses to total loans 1.02 % 1.10 %

Allowance for credit losses to non-accrual loans 3 2.75x 2.48x

Non-accrual loans to total loans 3 0.37 % 0.44 %

Capital ratios:

Tangible common equity to tangible assets 4 8.76 % 11.27 %

Total capital (to risk-weighted assets) 14.58 % 16.03 %

Tier 1 capital (to risk-weighted assets) 13.70 % 14.82 %

Tier 1 capital (to average assets) 8.85 % 10.80 %

Common equity Tier 1 capital (to risk-weighted assets) 13.70 % 14.69 %

Other data:

Number of branches 31 22

Full time equivalent employees 328 289

For the Years Ended December 31,

Selected operating data:

Net income per common share:

Performance and other financial ratios:

Tax-equivalent net interest margin 6 3.17 % 3.55 % 3.98 %

Cash dividend payout ratio on common stock 7 40.52 % 41.07 % 31.87 %

Cash dividends per common share $ 0.94 $ 0.92 $ 0.80

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Executive Summary

Annual earnings were $33.2 million in 2021 compared to $30.2 million in 2020. Diluted earnings were $2.30 per share in 2021, compared to $2.22 per share in 2020.

The following are highlights of operating and financial performance for the year ended December 31, 2021:

•Merger-related one-time and conversion costs reduced net income by $4.9 million, net of taxes, or 34 cents per share for the year ended December 31, 2021. Return on average assets ("ROA") and return on average equity ("ROE") were also significantly impacted by provisions for credit losses on acquired loans and shares issued in conjunction with the merger. As shown in the reconciliation of GAAP to non-GAAP financial measures on page 28, year-to-date ROA of 0.94% and ROE 8.43% would have been 1.08% and 9.67%, respectively, compared to 1.04% and 8.60% in the prior year.

•Loans increased $167.1 million in 2021, or 8%, to $2.256 billion at December 31, 2021, from $2.089 billion at December 31, 2020. Year-over-year growth was largely attributable to $419.4 million in loans from the American River Bank ("ARB") acquisition on August 6, 2021. Non-PPP loan originations of $181.7 million for the year were concentrated in commercial and real estate loans and compared to $165.5 million in 2020. Payoffs included $218.1 million non-PPP loans compared to $169.2 million in 2020. In 2021, PPP loan originations were $136.2 million and PPP loans forgiven and paid off were $328.5 million.

•Credit quality remains strong with non-accrual loans representing 0.37% of the Bank's loan portfolio as of December 31, 2021, compare to 0.44% at December 31, 2020. During 2021, we reversed $1.4 million in credit losses on loans and $992 thousand in credit losses on unfunded commitments. These reversals compared to provisions for credit losses on loans of $4.6 million and provisions for credit losses on unfunded commitments of $1.6 million in the prior year. 2021 activity included the effects of the business combination with ARB, partially offset by ongoing improvements in the underlying economic forecasts. 2020 credit loss provisions included significant qualitative adjustments for uncertainties associated with the COVID-19 pandemic as well as the adoption of the current expected credit loss methodology.

•Deposits grew $1.304 billion, or 52%, to $3.809 billionat December 31, 2021, compared to $2.504 billion at December 31, 2020. Growth was comprised of $790.0 million related to the August 6, 2021 ARB acquisition, new accounts and growth in the existing customer base. Non-interest bearing deposits grew by $555.6 million, or 41%, in 2021 and made up 50% of total deposits at year end. Cost of deposits remained low at 0.07% for the full year of 2021, down from 0.11% in 2020. Additionally, as part of our liquidity management, the Bank maintained $173.1 million and $173.4 million in off-balance sheet deposits with deposit networks at December 31, 2021 and 2020, respectively.

•Net interest income totaled $105.0 million and $96.7 million in 2021 and 2020, respectively. The $8.3 million increase in 2021 was primarily due to higher average loan and investment securities balances and higher SBA PPP loan fee accretion income. These increases were partially offset by $1.3 million in accelerated discount accretion on the early redemption of a subordinated debenture in the first quarter of 2021, and lower yields on investment securities. The tax-equivalent net interest margin decreased by 38 basis points to 3.17% in 2021, compared to 3.55% in 2020 for the reasons already mentioned.

•The efficiency ratio was 63.12% in 2021, up from 55.56% in 2020. As shown in the reconciliation of GAAP to non-GAAP financial measures on page 28, the 2021 efficiency ratio excluding merger-related one-time and conversion costs would have been 57.51%.

•All capital ratios were above regulatory requirements for a well-capitalized institution. The total risk-based capital ratio for Bancorp was 14.6% at December 31, 2021 and 16.0% at December 31, 2020. Tangible common equity to tangible assets declined to 8.8% at December 31, 2021 from 11.3% at December 31, 2020 primarily due to share repurchases and growth in excess liquidity from an increase in legacy Bank of Marin deposits (refer to footnote 4 on page 26 for definition of this non-GAAP financial measure). The total risk-based capital ratio for the Bank was 14.4% at December 31, 2021 and 15.8% at December 31, 2020.

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•The Board of Directors declared a cash dividend of $0.24 per share on January 21, 2022. This is the 67th consecutive quarterly dividend paid by Bank of Marin Bancorp. The cash dividend is payable on February 11, 2022 to shareholders of record at the close of business on February 4, 2022.

Statement Regarding Use of Non-GAAP Financial Measures

In this Form 10-K, Bancorp's financial results are presented in accordance with GAAP and refer to certain non-GAAP financial measures. Management believes that presentation of operating results using non-GAAP financial measures provides useful supplemental information to investors and facilitates the analysis of Bancorp's operating results and comparison of operating results across reporting periods. Management also uses non-GAAP financial measures to establish budgets and manage Bancorp's business. A reconciliation of the GAAP financial measures to comparable non-GAAP financial measures is presented below.

Reconciliation of GAAP and Non-GAAP Financial Measures

Year ended December 31,

Net income

Merger-related one-time and conversion costs:

Personnel and severance 3,005 — —

Professional services 1,976 — —

Data processing 1,127 — —

Total merger costs before tax benefits 6,458 — —

Income tax benefit of merger-related expenses (1,547) — —

Diluted earnings per share

Diluted earnings per share (GAAP) $ 2.30 $ 2.22 $ 2.48

Merger-related one-time and conversion costs, net of tax benefits 0.34 — —

Comparable diluted earnings per share (non-GAAP) $ 2.64 $ 2.22 $ 2.48

Return on average assets

Return on average assets (GAAP) 0.94 % 1.04 % 1.34 %

Comparable return on average assets (non-GAAP) 1.08 % 1.04 % 1.34 %

Return on average equity

Return on average equity (GAAP) 8.43 % 8.60 % 10.49 %

Comparable return on average equity (non-GAAP) 9.67 % 8.60 % 10.49 %

Efficiency ratio

Merger-related expenses (6,458) — —

Comparable efficiency ratio (non-GAAP) 57.51 % 55.56 % 55.21 %

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Net Interest Income

Net interest income is the interest earned on loans, investment securities and other interest-earning assets minus the interest expense incurred on deposits and other interest-bearing liabilities. Net interest income is affected by changes in general market interest rates and by changes in the amounts and composition of interest-earning assets and interest-bearing liabilities. Interest rate changes can create fluctuations in net interest income and/or margin due to an imbalance in the timing of repricing or maturity of assets or liabilities. We manage interest rate risk exposure with the goal of optimizing the effect of interest rate volatility on net interest income.

Net interest margin is expressed as net interest income divided by average interest-earning assets. Net interest rate spread is the difference between the average rate earned on total interest-earning assets and the average rate incurred on total interest-bearing liabilities. Both of these measures are reported on a taxable-equivalent basis. Net interest margin is the higher of the two because it reflects interest income earned on assets funded with non-interest-bearing sources of funds, which include demand deposits and stockholders’ equity.

The following table compares interest income, average interest-earning assets, interest expense, and average interest-bearing liabilities for the periods presented. The table also presents net interest income, net interest margin and net interest rate spread for the years indicated.

Average Statements of Condition and Analysis of Net Interest Income

Year ended Year ended Year ended

Interest Interest Interest

Average Income/ Yield/ Average Income/ Yield/ Average Income/ Yield/

Assets

Liabilities and Stockholders' Equity

Tax-equivalent net interest rate spread 3.04 % 3.41 % 3.74 %

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Analysis of Changes in Net Interest Income

The following table presents the effects of changes in average balances (volume) or changes in average rates on tax-equivalent net interest income for the years indicated. Volume variances are equal to the increase or decrease in average balances multiplied by prior period rates. Rate variances are equal to the increase or decrease in rates multiplied by prior period average balances. Mix variances are attributable to the change in yields or rates multiplied by the change in average balances.

2021 Compared to 2020

Net interest income totaled $105.0 million and $96.7 million in 2021 and 2020, respectively. The $8.3 million increase in 2021 was primarily due to higher average loan and investment securities balances and higher SBA PPP loan income. These increases were partially offset by $1.3 million in accelerated discount accretion on the early redemption of a subordinated debenture in the first quarter of 2021, and lower yields on investment securities.

We recognized $8.3 million in SBA PPP fees, net of cost in 2021, compared to $3.8 million in 2020. As of December 31, 2021, $2.5 million SBA PPP fees, net of deferred costs remained outstanding and will be recognized into income in future periods.

On March 15, 2021, we redeemed the $2.8 million subordinated debenture. The redemption consisted of $4.1 million principal balance, quarterly interest due, and $1.3 million in accelerated accretion of purchase discount. The subordinated debenture carried an average interest rate of 5.68% in 2020.

The tax-equivalent net interest margin decreased 38 basis points to 3.17% in 2021, from 3.55% in 2020 for the reasons already mentioned and as shown in the above table. The SBA PPP loans improved the 2021 net interest margin by 10 basis points, and the early redemption of the subordinated debenture reduced it by 4 basis points.

2020 Compared to 2019

Net interest income totaled $96.7 million and $95.7 million in 2020 and 2019, respectively. The $1.0 million increase in 2020 was primarily due to SBA PPP loans and lower rates on interest-bearing deposits, largely offset by lower yields on earning-assets, except for investment securities where we collected prepayment penalties on called securities in 2020. Notable balance increases occurred in interest-earning deposits with other banks, commercial real estate loans and deposits. The tax-equivalent net interest margin decreased 43 basis points to 3.55% in 2020, from 3.98% in 2019 for the reasons already mentioned and as shown in the above table. Additionally, the SBA PPP loans lowered the 2020 net interest margin by 6 basis points.

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Market Interest Rates

Market interest rates are, in part, based on the target federal funds interest rate (the interest rate banks charge each other for short-term borrowings) implemented by the Federal Reserve Open Market Committee ("FOMC").

In response to the evolving risks to economic activity posed by the COVID-19 pandemic, the FOMC made two emergency cuts totaling 150 basis points to the federal funds rate in March 2020. The federal funds target rate range resided between 0.0% to 0.25% in 2021 and 2020, putting downward pressure on our asset yields and net interest margin. In its January 26, 2022 meeting the FOMC kept the federal funds target rate range between 0.0% to 0.25%, but signaled that it will raise interest rates in 2022 to combat inflation. Our net interest margin should benefit from a rising interest rate environment. See ITEM 7A. Quantitative and Qualitative Disclosure about Market Risk for further information.

Provision for Credit Losses on Loans

We recorded a $1.4 million reversal of the provision for credit losses on loans in 2021, compared to a $4.6 million provision for credit losses in 2020 and $900 thousand provision for credit losses in 2019. The net provision reversal in 2021 was primarily due to continued improvements in Moody's Analytics' Baseline Forecast of California unemployment rates and adjustments to qualitative risk factors due to a decline in the volume of loans downgraded to substandard classification, fewer delinquencies, and the elimination of an allowance related to a commercial real estate loan that had been individually analyzed for potential credit losses in the previous periods and paid off in 2021. These reversals were partially offset by an increase in the allowance for credit losses related to qualitative risk factor adjustments for recent changes in executive leadership and senior lending positions, and integration of ARB.

The provision for credit losses in 2020 calculated under the incurred loss method (prior to the adoption of the excepted credit loss method on December 31, 2020) was largely due to the uncertainty about the impact of the COVID-19 pandemic on the local and regional economies and our customers at that time. In addition, under the CECL method, we increased our allowance for credit losses by approximately $925 thousand for previously acquired loans (i.e., non-purchased credit deteriorated or "non-PCD" loans); whereas, under previous GAAP (incurred loss method) we did not record an allowance on our unimpaired previously acquired non-PCD loans. The pandemic also negatively affected the financial condition of many of our borrowers, which was partially alleviated by our payment relief program under the 2020 CARES Act and the SBA PPP. The provision for credit losses in 2019 accounted for under the incurred loss methodology was consistent with loan growth.

For additional information about the allowance for credit losses and transition from the incurred loss method to the CECL method in 2020, see the Critical Accounting Estimates section above and Notes 1 and 3 to the Consolidated Financial Statements in ITEM 8 of this report.

Non-interest Income

The table below details the components of non-interest income.

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2021 Compared to 2020

Non-interest income totaled $10.1 million and $8.6 million in 2021 and 2020, respectively. The $1.5 million increase was primarily due to the collection of $1.1 million in benefits on bank-owned life insurance policies and an increase in service charges and interchange fees related to the expanded deposit base. In March 2020, we implemented temporary waivers for all ATM fees, overdraft fees and early withdrawal penalties for time deposits to help ease the financial burden customers began experiencing due to the pandemic. We reinstituted the fees in May 2021. Additionally, Wealth Management and Trust income increased due to the addition of new accounts and favorable market performance in 2021. Increases were partially offset by the $931 thousand reduction in gains on sales of investment securities.

2020 Compared to 2019

Non-interest income totaled $8.6 million and $9.1 million in 2020 and 2019, respectively. The $534 thousand decline was primarily due to $551 thousand lower service charges on deposit accounts and ATM fees, as these fees were waived during the pandemic, lower income from bank-owned life insurance ("BOLI") policies due to a $562 thousand benefit collected on BOLI policies in the third quarter of 2019 (partially offset by $283 thousand underwriting expenses for two new BOLI policies in the first quarter of 2019), $182 thousand lower fee income from one-way deposit sales to third-party deposit networks and $145 thousand lower dividends on FHLB stock, partially offset by $860 thousand net gains on the sale of investment securities.

Non-interest Expense

The table below details the components of non-interest expense.

Other non-interest expense:

2021 Compared to 2020

Non-interest expense increased $14.1 million to $72.6 million in 2021 from $58.5 million in 2020. The largest increase of $6.5 million came from acquisition related one-time and conversion costs. In addition to $3.0 million in one-time merger cost, salaries and related benefits rose another $4.5 million due to increased numbers of employees, regularly scheduled annual merit and related increases, and lower deferred loan origination costs. Professional services included $817 thousand more in consulting expenses for PPP loan forgiveness application processing, investment advisory services, and legal costs. Data processing increased by an additional $828 thousand primarily due to increases core processing and mobile banking systems charges, and other categories increased due to the larger size of the bank. FDIC insurance increased by $415 thousand due to an increase in our deposit base. Charitable contributions decreased due to supplemental contributions in 2020 related to the pandemic.

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2020 Compared to 2019

In 2020, non-interest expense increased by $617 thousand to $58.5 million from $57.8 million. The largest increases came from the occupancy expenses (primarily due to lease renewals for our existing headquarters offices and new lease for a loan production office in San Mateo, common area maintenance and janitorial expenses), and charitable contributions due to our outreach to nonprofit organizations in our community during the pandemic. The decrease in data processing costs was due to our digital platform conversion in 2019. While salaries and related benefits were relatively unchanged year-over-year, annual merit and related increases were mostly offset by $915 thousand in SBA PPP-related deferred loan origination costs.

Provision for Income Taxes

Income tax provisions reflect accruals for taxes at the applicable rates for federal income tax and California franchise tax based upon reported pre-tax income. Provisions also reflect permanent differences between income for tax and financial reporting purposes (such as earnings on tax exempt loans and municipal securities, BOLI, low-income housing tax credits, and stock-based compensation from the exercise of stock options, disqualifying dispositions of incentive stock options and vesting of restricted stock awards).

The provision for income taxes totaled $11.7 million at an effective tax rate of 26.0% in 2021, compared to $10.3 million at an effective tax rate of 25.5% in 2020 and $11.7 million at an effective tax rate of 25.4% in 2019. The increase in the provision in 2021 compared to 2020 reflected higher pre-tax income. The 50 basis point increase in the effective tax rate in 2021 as compared to 2020 was primarily due to non-deductible merger expenses and executive compensation, partially offset by higher BOLI income and tax exempt loan and investment securities interest income. The slight increase in the effective tax rate in 2020 compared to 2019 was due to a favorable deferred tax liability true-up recognized in 2019 and a lower tax benefit from BOLI income in 2020.

We file a consolidated return in the U.S. Federal tax jurisdiction and a combined return in the State of California tax jurisdiction. There were no ongoing federal or state income tax examinations at the issuance of this report. At December 31, 2021 and 2020, neither the Bank nor Bancorp had accruals for interest or penalties related to unrecognized tax benefits.

FINANCIAL CONDITION

Our assets increased $1.4 billion from December 31, 2020 to December 31, 2021. Increases reflected both the acquisition of ARB and organic growth.

Investment Securities

We maintain an investment securities portfolio to provide liquidity and to generate earnings on funds that have not been loaned to customers. Management determines the maturities and types of securities to be purchased based on liquidity and interest rate risk position, and the desire to attain a reasonable investment yield balanced with risk exposure. The table below shows the composition of the debt securities portfolio by expected maturity at December 31, 2021 and 2020. Expected maturities differ from contractual maturities because the issuers of the securities may have the right to call or prepay obligations with or without call or prepayment penalties. We estimate and update expected maturity dates regularly based on current and historical prepayment speeds. The weighted average life of the investment portfolio at December 31, 2021 and 2020 was approximately six and five years, respectively.

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December 31, 2021 Within 1 Year 1-5 Years 5-10 Years After 10 Years Total

Held-to-maturity:

Available-for-sale:

December 31, 2020 Within 1 Year 1-5 Years 5-10 Years After 10 Years Total

Held-to-maturity:

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December 31, 2020 Within 1 Year 1-5 Years 5-10 Years After 10 Years Total

Available-for-sale:

1 Book value reflects cost, adjusted for accumulated amortization and accretion.

2 Weighted average calculation is based on amortized cost of securities.

3 Yields on tax-exempt municipal bonds are presented on a taxable equivalent basis, using federal tax rate of 21%.

The amortized cost of our investment securities portfolio increased $1.03 billion or 214% during 2021. We purchased $620.2 million in securities in 2021 designated as available-for-sale to provide flexibility for liquidity and interest rate risk management. We also purchased $305.3 million in securities in 2021 designated as held-to-maturity. These purchases were offset by $181.7 million of paydowns, calls and maturities, and $6.6 million of sales during 2021. We also acquired $297.8 million in securities from ARB. The weighted average yield on the purchases of securities was 1.68% for the 2021 year and 1.60% for the fourth quarter of 2021.

During 2021, we purchased $287.6 million in agency mortgage-backed securities ("MBSs"), $271.7 million in debentures of government sponsored agencies, $268.6 million in agency collateralized mortgage obligations ("CMOs"), $60.7 million in obligations of state and political subdivisions and $37.0 million in corporate bonds. We consider agency debentures and CMOs issued by U.S. government sponsored entities to have low credit risk as they carry the credit support of the U.S. federal government. The debentures, CMOs and MBS issued by U.S. government sponsored agencies, SBA-backed securities and U.S. Treasury securities made up 85.6% of the portfolio at December 31, 2021, compared to 77.9% at December 31, 2020. See the discussion in the section captioned “Securities May Lose Value due to Credit Quality of the Issuers” in ITEM 1A Risk Factors above.

At December 31, 2021, distribution of our investment in obligations of state and political subdivisions was as follows:

Within California:

Outside California:

The portion of the portfolio outside the state of California is distributed among thirteen states. Of the total investment in obligations of state and political subdivisions, the largest concentrations outside California are in

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Texas (38.4%), Washington (16.4%), and Wisconsin (6.7%). Our investment in obligations issued by municipal issuers in Texas are either guaranteed by the AAA-rated Texas Permanent School Fund ("PSF") or backed by revenue sources from essential services (such as utilities and transportation). We have $6.0 million in obligations of Texas school district issuers having high concentrations in oil and gas industry taxpayers and all of them have credit guarantees from the PSF.

Investments in states, municipalities and political subdivisions are subject to an initial pre-purchase credit assessment and ongoing monitoring. Key considerations include:

•The soundness of a municipality’s budgetary position and stability of its tax revenues

•Debt profile and level of unfunded liabilities, diversity of revenue sources, taxing authority of the issuer

•Local demographics/economics including unemployment data, largest local taxpayers and employers, income indices and home values

•For revenue bonds, the source and strength of revenue for municipal authorities including obligors' financial condition and reserve levels, annual debt service and debt coverage ratio, and credit enhancement (such as insurer’s strength)

•Credit ratings by major credit rating agencies

Loans

Loans Outstanding by Class at December 31

Real estate

Allowance for credit losses on loans (23,023) (22,874)

Total loans, net of allowance for credit losses $ 2,232,622 $ 2,065,682

Loans increased $167.1 million in 2021, or 8%, to $2.256 billion at December 31, 2021, from $2.089 billion at December 31, 2020. Year-over-year growth was largely attributable to $419.4 million in loans from the ARB acquisition on August 6, 2021. Non-PPP loan originations of $181.7 million for the year were concentrated in commercial and real estate loans and compared to $165.5 million in 2020. 2021 payoffs included $218.1 million non-PPP loans, compared to $169.2 million in 2020. In 2021, PPP loan originations were $136.2 million and PPP loans forgiven and paid off were $328.5 million.

Non-PPP payoffs as a percentage of beginning of the year loan balances were 10.4% in 2021 and 9.2% in 2020. Approximately 86% and 77%, of total loans were secured by real estate at December 31, 2021 and 2020, respectively. The increase in the percentage secured by real estate from 2020 to 2021 was primarily due to a $180.4 million reduction in unsecured loans guaranteed by the SBA under the PPP, which are included in commercial and industrial loans. For additional information on loan concentration risk, see ITEM 1A, Risk Factors.

The following table summarizes our commercial real estate loan concentrations by the county in which the property was located as of December 31, 2021 and 2020.

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Commercial Real Estate Loans Outstanding by County

(dollars in thousands; unaudited) December 31, 2021 December 31, 2020

Commercial real estate loans increased $315.2 million in 2021, compared to a $68.5 million increase in 2020. The increase was primarily due to the ARB acquisition and expanded footprint in Northern California. Of the commercial real estate loans at December 31, 2021, 75% were investor-owned and 25% were owner-occupied. Almost the entire commercial real estate loan portfolio is comprised of term loans for which the primary source of repayment is either the cash flow from the leasing activities of the real estate collateral or the operating cash flow of the owner occupant.

We occasionally provide interest-only term loans to borrowers who exhibit strong financial capacity and/or for commercial real estate loans during the occupancy stabilization period. After the initial interest-only payment period, these loans will normally require principal and interest payments. In addition, we may make interest-only concessions in a modified troubled debt restructuring ("TDR"). At December 31, 2021 and 2020, approximately 5.0% and 3.4%, respectively, of our commercial real estate loans contained an interest-only feature as part of the loan terms. All of these loans were current with their payments as of December 31, 2021. Except for three substandard classified loans to two borrowing relationships totaling $24.7 million (or 1.6%) as of December 31, 2021, all were considered to have low credit risk (graded "Pass").

The following table shows an analysis of construction loans by type and county as of December 31, 2021 and 2020.

Construction Loans Outstanding by Type and County

(dollars in thousands; unaudited) December 31, 2021 December 31, 2020

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(dollars in thousands; unaudited) December 31, 2021 December 31, 2020

County Amount Percent of Construction Loans Amount Percent of Construction Loans

Construction loans increased by $46.8 million in 2021, compared to an increase of $12.0 million in 2020. The increase in 2021 was primarily due to $48.8 million advanced on existing construction loans, $13.2 million in loans assumed in the ARB acquisition and $7.2 million in new financing. These increases were partially offset by $19.5 million in payoffs and $2.9 million in conversions to commercial real estate financing. The increase in 2020 primarily resulted from additional borrowings under existing construction loans as well as advances on six new construction loans to well-known, experienced builders. The increase was partially offset by the successful completion of projects, one of which converted to a permanent commercial real estate loan.

The following table presents the amortized costs and maturity distribution of our loans by class as of December 31, 2021 based on their contractual maturity dates. Maturities do not include scheduled payments or potential prepayments.

Loan Maturity Distribution

(in thousands; unaudited)

Real estate

1 Commercial and industrial due after 1 but within 5 years includes SBA PPP loans totaling $111.2 million (net of $2.5 million in unrecognized fees and costs), the majority of which are expected to be forgiven by the SBA in 2022.

2 Construction loans that mature after 5 years are structured to convert to permanent financing after the initial construction period.

The following table shows the mix of variable-rate loans to fixed-rate loans due after one year by class as of December 31 2021. The large majority of the variable-rate loans are tied to independent indices (such as the Prime Rate or a Treasury Constant Maturity Rate). Most loans with original terms of more than five years have provisions for the fixed rates to reset, or convert to variable rates, after three, five or seven years. These loans are included in variable-rate balances below.

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Loan Interest Rate Sensitivity - Due After One Year

(in thousands; unaudited) Fixed Variable Total

Real estate —

1 Commercial and industrial includes SBA PPP 1% fixed rate loans totaling $111.2 million (net of $2.5 million in unrecognized fees and costs), the majority of which are expected to be forgiven by the SBA in 2022.

Allowance for Credit Losses on Loans

As of December 31, 2021, we calculated the allowance for credit losses using the current expected loss methodology, or CECL, which required us to estimate credit losses over the expected life of a loan and consider future changes in macroeconomic conditions. All specifically identifiable and quantifiable losses are charged off against the allowance. The ultimate adequacy of the allowance depends on a variety of factors beyond our control, including the real estate market, changes in interest rates and economic and political environments. Based on the current conditions of the loan portfolio and reasonable and supportable forecasts, management believes that the $23.0 million allowance for credit losses at December 31, 2021 was adequate to absorb expected credit losses in our loan portfolio, but provides no assurance that adverse changes in economic conditions or other circumstances over the remaining terms of our loans will not result in increased losses in the portfolio. For information on our allowance for credit losses methodology and adoption of FASB ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, effective December 31, 2020, refer to Notes 1 and 3 to the Consolidated Financial Statements in ITEM 8 of this report.

The allowance for credit losses to loans was 1.02% at December 31, 2021 and 1.10% at December 31, 2020. The allowance for credit losses to loans, excluding SBA PPP loans and previously acquired loans was 1.07 and 1.27% at year-end 2021 and 2020, respectively (for a discussion of this non-GAAP financial measure, refer to ITEM 7, Reconciliation of GAAP and Non-GAAP Financial Measures section of this report).

The $149 thousand increase in the allowance for credit losses on loans in 2021 was largely due to loans acquired from ARB, partially offset by improvements in economic factors that drive the quantitative portion of the allowance. The $6.2 million increase in the allowance for credit losses in 2020 was almost entirely due to the impact of the COVID-19 pandemic and its effect on the local and regional economies and economic outlook coupled with the transition to the CECL method. For further information, refer to the Provision for Credit Losses section above, and Notes 1 and 3 to the Consolidated Financial Statements in ITEM 8 of this report.

Due to the high credit quality of our loan portfolio, net charge-offs have been minimal for the past several years. Net recoveries totaled $93 thousand in 2021, compared to net charge-offs of $1 thousand in 2020 and $44 thousand in 2019.

The following table shows the allocation of the allowance by loan class as well as the percentage of total loans in each of the same loan classes.

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Allocation of Allowance for Credit Losses

Real estate:

Unallocated allowance 2,286 N/A 1,300 N/A

Total allowance for credit losses $ 23,023 $ 22,874

The table below shows the activity in the allowance for credit losses for each of the five years presented below.

Allowance for Credit Losses Rollforward

Impact of CECL adoption — 1,604 —

Provision for (reversal of) credit losses (1,449) 4,594 900

Initial allowance for PCD loans 1,505

Loans charged-off:

Commercial and industrial — (30) (75)

Installment and other consumer (5) (1) (3)

Total loans charged-off (5) (31) (78)

Loans recovered:

Commercial and industrial 14 27 22

Real estate:

Commercial, investor-owned — — 12

Construction 34 3 —

Home equity 50 — —

Net loans (charged-off) recovered 93 (1) (44)

Net recoveries (charge-offs) to average loans NM NM NM

NM - Not meaningful.

Net charge-offs and recoveries for the years ended December 31, 2021, 2020 and 2019 were considered insignificant.

The following shows non-performing assets and loans modified in a troubled debt restructuring ("TDR") for each of the years in the five-year period ended December 31, 2021.

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Non-Performing and Loans and Troubled Debt Restructurings

(dollars in thousands; unaudited) 2021 2020

Non-accrual loans:

Real estate:

Commercial, investor-owned 694 1,610

Installment and other consumer — 17

Accruing TDR loans:1

Commercial and industrial $ 1,183 $ 1,021

Real estate:

Commercial, investor-owned 179 3,305

Installment and other consumer 607 735

Total non-accrual and accruing TDR loans $ 10,475 $ 14,304

Criticized and classified loans:

Doubtful $ 114 $ —

Allowance for credit losses to non-accrual loans 2.75x 2.48x

Non-accrual loans to total loans 0.37 % 0.44 %

1 Excludes TDR loans on non-accrual status that are included above.

Non-Accrual and TDR

Non-accrual loans decreased by $857 thousand primarily due to $1.0 million in payoffs and paydowns, partially offset by a $114 thousand well-secured investor-owned commercial real estate loan assumed in the ARB acquisition and one $67 thousand home equity loan placed on non-accrual status in 2021.

Non-accrual loans increased $9.0 million in 2020, primarily due to the placement of two existing well-secured owner-occupied commercial real estate TDR loans, secured by one property, totaling $7.1 million on non-accrual, as well as two well-secured investor-owned commercial loans totaling $1.6 million that were placed on non-accrual in 2020. In addition, we designated five loans totaling $2.1 million as TDRs during 2020, resulting in an overall increase of $2.8 million in total non-accrual and accruing TDR loans from 2019 to 2020. These increases were partially offset by approximately $1.0 million in paydowns and payoffs of non-accrual and TDR loans.

Total accruing TDR loans were $2.1 million and $5.1 million as of December 31, 2021 and 2020, respectively. The $3.0 million decrease in 2021 was primarily due to $4.0 million in paydowns and payoffs, partially offset by two loans totaling $1.0 million that were designated as TDRs during 2021. The $6.2 million decrease from 2019 to 2020 primarily related to the two existing well-secured commercial real estate TDR loans totaling $7.1 million that were transferred to non-accrual status coupled with payoffs and paydowns, partially offset by the $2.1 million in new TDR loans mentioned above.

For information regarding temporary relief from TDR accounting afforded by the CARES Act, refer to the Executive Summary section above and Note 3 to the Consolidated Financial Statements in ITEM 8, under “Troubled Debt Restructuring."

Criticized and Classified Loans

Loans designated as special mention decreased by $13.6 million in 2021, primarily due to $18.9 million in paydowns and payoffs, $33.1 million in upgrades to a pass risk rating and two loans that were downgraded from special mention to substandard totaling $5.4 million. These decreases were partially offset by $17.2 million in loans that were downgraded from pass/watch, $13.5 million in loans assumed in the ARB acquisition, and $13.2 million in loans that were upgraded from substandard to special mention during 2021. Of the $17.2 million in downgrades, $13.2 million were well-secured by commercial real estate and the remaining $4.0 million in commercial loans had strong support. Loans designated special mention increased by $13.5 million in 2020, driven by loan downgrades

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totaling $31.0 million. Of these downgrades, approximately $24.5 million were loans to borrowers that were impacted by the pandemic, all of which were well-secured by commercial real estate. These additions to special mention were mostly offset by $15.8 million in upgrades to pass risk ratings, paydowns and payoffs, and $2.2 million in loans downgraded from special mention to substandard in 2020. Loans designated as special mention exhibit potential weakness that deserve close attention.

Loans classified substandard increased by $13.3 million in 2021, primarily due to downgrades totaling $25.4 million and $2.3 million in substandard loans assumed in the ARB acquisition. Of the downgraded loans, $24.2 million were secured by commercial real estate. The downgrades were partially offset by $13.2 million in upgrades to special mention and $4.2 million in paydowns and payoffs. Loans classified substandard increased by $15.9 million in 2020, primarily due to downgrades totaling $18.5 million. Of these loans, $13.4 million were to borrowers that requested payment relief due to the pandemic, all of which were well-secured by commercial real estate. These downgrades to substandard were partially offset by approximately $2.8 million in payoffs and risk rating upgrades. Loans classified substandard decreased by $2.7 million during 2019 primarily due to the payoff of a land development loan.

Refer to Note 3 to the Consolidated Financial Statements in ITEM 8 of this report for an allocation of criticized and classified loans by loan class.

Other Assets

BOLI totaled $61.5 million at December 31, 2021, compared to $43.6 million at December 31, 2020, and is recorded in other assets. The increase of $17.9 million was primarily due to the acquisition of $15.7 million in ARB policies and the purchase of $1.9 million in new policies.

Interest receivable and other assets totaled $51.4 million and $36.5 million at December 31, 2021 and 2020, respectively. The $14.9 million increase was primarily due to a $6.4 million increase in net deferred tax assets, a $4.9 million increase in FHLB stock and a $2.6 million increase in accrued interest on investment securities as discussed below.

Net deferred tax assets totaled $13.3 million and $6.9 million at December 31, 2021 and 2020, respectively. Deferred tax assets consist primarily of tax benefits expected to be realized in future periods related to temporary differences such as the allowances for credit losses and unfunded loan commitments, net operating loss carryforwards, and deferred compensation and salary continuation plans. The $6.4 million increase in net deferred tax assets in 2021 was primarily due to a $4.5 million decrease in deferred tax liabilities related to changes in unrealized gains on available-for-sale investment securities, a $1.6 million increase in deferred tax assets related to the change in deferred compensation plan and salary continuation plan, a $781 thousand increase in deferred tax assets related to accrued but unpaid expenses and a $640 thousand increase in deferred tax assets related to fair value adjustments on acquired loans. These increases were partially offset by a $820 thousand increase in deferred tax liabilities related to the increase in core deposit intangibles. Management believes deferred tax assets will be realizable due to our consistent record of earnings and the expectation that earnings will continue at a level adequate to realize such benefits. Therefore, no valuation allowance was established as of December 31, 2021 or 2020. For additional information, refer to Note 11 to the Consolidated Financial Statements in ITEM 8 of this report.

We held $16.7 million and $11.9 million of FHLB stock recorded at cost in other assets at December 31, 2021 and 2020, respectively. The increase in 2021 resulted from the acquisition of $4.9 million of ARB's FHLB stock. The FHLB paid $760 thousand, $654 thousand and $799 thousand in cash dividends in 2021, 2020 and 2019, respectively. For additional information, refer to Note 2 to the Consolidated Financial Statements in ITEM 8 of this report.

Accrued interest on investment securities totaled $4.8 million and $2.2 million at December 31, 2021 and 2020, respectively. The increase was primarily due to purchases of $925.6 million in securities and acquisition of $297.8 million in securities from ARB.

Deposits

Deposits grew by $1.304 billion, to $3.809 billion at December 31, 2021, compared to $2.504 billion at December 31, 2020. Non-interest bearing deposits grew by $555.6 million in 2021 and made up 50% of total

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deposits at year-end. See ITEM 1A, Risk Factors, for a discussion of potential risks associated with concentrations and volatility due to activity of our large deposit customers and impact of the SBA PPP loans. Our relationship banking model is the foundation for the strong deposit base and allows us to proactively and strategically address changes in the interest rate environment and technology adoption by our customers.

Distribution of Average Deposits

The table below shows the relative composition of our average deposits for 2021 and 2020. For average rates paid on deposits, refer to Average Statements of Condition and Analysis of Net Interest Income table in ITEM 7- Management's Discussion and Analysis of Financial Condition and Results of Operations.

As of December 31,

1 Money market balances include Insured Cash Sweep® ("ICS") in both 2021 and 2020. Demand Deposit Marketplace SM ("DDM") and ICS balances are discussed in Note 6 to the Consolidated Financial Statements in ITEM 8 of this report.

Total estimated uninsured deposits as of December 31, 2021 and December 31, 2020 were $1.830 billion and $1.116 billion, respectively.

Maturities of Uninsured Time Deposits

The following table shows time deposits by account that are in excess of $250,000 by time remaining to maturity at December 31, 2021.