Bank of Marin Bancorp

Part I

Explanatory Note

On February 23, 2026, the Board of Directors (the “Board”) of Bank of Marin Bancorp (the “Company”), based on the recommendation of, and after consultation with, the Board’s Audit Committee, the Company’s management and the Company’s independent registered public accounting firm, Baker Tilly US, LLP, concluded that the Company’s previously issued audited consolidated financial statements as of and for the years ended December 31, 2024 and 2023 and the unaudited financial statements as of and for the interim periods ended September 30, 2025, June 30, 2025, March 31, 2025, September 30, 2024, June 30, 2024, and March 31, 2024, (the “Affected Periods”) included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 and the Company’s Quarterly Reports on Form 10-Q for each of the applicable interim periods (the financial statements contained in such reports, the “Affected Financials”), should no longer be relied upon due to certain errors made in the Company’s accounting related to the classification of certain reciprocal network deposits and related interest expense as non-interest bearing deposits and non-interest expense that were determined to be material to the Company’s financial condition as reflected in the Affected Financials. Similarly, related earnings releases, press releases, shareholder communications, investor presentations or other communications describing relevant portions of the Affected Financials should no longer be relied upon.

The adjustments required to be made in the Affected Financials were as a result of errors that the Company’s current management identified during the Company’s annual review process related to the preparation of its consolidated financial statements for the year ended December 31, 2025. The errors resulted in impacts to certain line items of the Company’s Consolidated Statement of Condition and Consolidated Statement of Comprehensive (Loss) Income but did not impact the Company’s net income or earnings per share for any of the Affected Periods. Certain deposits were included in non-interest bearing deposits when they should have been included in interest bearing deposits. Additionally, the expense related thereto was included in deposit network fees within non-interest operating expense instead of interest expense, although the mistaken classification of the expense was determined not to be material and had no impact on net income or earnings per share. The required reclassifications on the balance sheet from non-interest bearing deposits to interest bearing deposits were determined to be material, although the reclassifications are not expected to have any impact on total Consolidated Statement of Condition amounts, including total deposits and stockholders’ equity for the Affected Periods. The adjustments to the Company’s Consolidated Statements of Comprehensive (Loss) Income for the Affected Periods were deemed necessary for consistency of presentation between prior periods once the adjustments were made to interest expense and non-interest expense for 2025. Because the corrections of this misstatement have, taken as a whole, been determined to be material to the Affected Financials, the Board concluded that the Affected Financials should no longer be relied upon.

The Affected Financials are corrected herein. Please refer to Note 19, Restatement of Prior Period Financial Statements (Quarterly Information Unaudited) in Item 8 - Financial Statements and Supplementary Data. In addition to the correction of the Affected Financials included in Note 19, financial information and related narrative discussion in Part II, Item 7. Management's Discussion of Financial Condition and Results of Operation, from the Affected Periods has been revised to reflect the corrected financial statements.

Impact on Internal Controls over Financial Reporting

See Item 9A, Controls and Procedures, for information related to the identified material weakness in internal control over financial reporting and the related remedial measures.

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 impact our earnings in future periods. Factors that could cause future results to vary materially from current management expectations include, but are not limited to, general economic conditions and the economic uncertainty in the United States and abroad, including economic or other disruptions to financial markets caused by acts of terrorism, war or other conflicts, impacts from inflation, supply chain disruptions, changes in interest rates (including the actions taken by the Federal Reserve to control inflation), California's unemployment rate, deposit flows, real estate values, and expected future cash flows on loans and securities; the impact of adverse developments at other banks, including bank failures, that impact general sentiment regarding the stability and liquidity of banks; costs or effects of acquisitions; competition; changes in accounting principles, policies or guidelines; changes in legislation or regulation; 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 differ materially from those expressed in our prior forward-looking statements are detailed in ITEM 1A, Risk Factors of this report. Forward-looking statements speak only as of the date they are made. Bancorp undertakes no obligation to release publicly the result of any revisions to these forward-looking statements that may be made to reflect events or circumstances that occur after the date the forward-looking statements are made or to reflect the occurrence of unanticipated events.