Bank of Marin Bancorp

Evaluation of Disclosure Controls and Procedures

Bank of Marin Bancorp and its subsidiary (the "Company") conducted an evaluation under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of our disclosure controls and procedures (as defined in Rule 13a-15(e) or 15d-15(e) under the Securities Exchange Act of 1934 (the “Act”)) as of the end of the period covered by this report. The term disclosure controls and procedures means controls and other procedures that are designed to ensure that information we are required to disclose in the reports that we file or submit under the Act (15 U.S.C. 78a et seq.) is recorded, processed, summarized and reported, within the time periods specified in the SEC's rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information we are required to disclose in the reports that we file or submit under the Act is accumulated and communicated to our management, including our principal executive and principal financial officers, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure. Based upon that evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective as of the end of the period covered by this report.

Previously Identified Material Weakness

As previously reported in our Annual Report on Form 10-K filed with the SEC on March 13, 2026, we identified a material weakness in internal control over financial reporting. Management did not design and implement adequate control activities related to the accounting for and classification of certain reciprocal deposits and transactions. This material weakness resulted from ineffective controls over the accounting for and classification of reciprocal network deposits. This resulted in (i) a material misclassification of deposits within the Consolidated Statements of Condition between interest-bearing deposits and non-interest bearing deposits and (ii) an immaterial misclassification of expenses within the Consolidated Statements of Comprehensive (Loss) Income, between interest expense and non-interest expense, with no impact to net (loss) income. This required a restatement of our annual consolidated financial statements for the years ended December 31, 2024 and 2023, and our unaudited interim condensed consolidated financial statements for the quarters ended September 30, 2025, June 30, 2025, March 31, 2025, September 30, 2024, June 30, 2024, and March 31, 2024. While only the statement of condition misclassification was significant enough to result in the material misstatement, management chose to revise the statement of comprehensive (loss) income as well for the affected periods in order to provide a more complete picture.

Remediation Plan for the Material Weakness

Since identifying the material weakness, management, under the oversight of the Audit Committee has taken the following steps to remediate this deficiency. The Company continues to execute on its remediation plan, which includes controls to:

•Enhance risk assessment procedures over reciprocal deposit networks to identify whether additional control activities are needed to conform to our accounting policies;

•Increase involvement of technical accounting resources for complex areas at initial onboarding and for periodic review; and

•Require formal documentation of technical conclusion and evidence of supervisory oversight for third party reciprocal deposit networks.

Changes in Internal Control over Financial Reporting

Other than the remediation efforts described above, during the quarter ended June 30, 2026, there were no significant changes that materially affected, or are reasonably likely to affect, our internal control over financial reporting. The term internal control over financial reporting, as defined by Rule 15d-15(f) of the Act, is a process designed by, or under the supervision of, the issuer's principal executive and principal financial officers, or persons performing similar functions, and affected by the issuer's board of directors, management and other personnel, to

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