Bank of Marin Bancorp : Expands Northern California Presence with Merger of and American River Bank

Bank of Marin Expands Northern California Presence with

Merger of Bank of Marin and American River Bank

Investor Presentation | April 19, 2021

Forward-Looking Statements

This presentation may contain certain forward-looking statements that are based on management's current expectations regarding economic, legislative, and regulatory issues that may impact Bancorp's earnings in future periods. 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 such as "will," "would," "should," "could" or "may." Factors that could cause future results to vary materially from current management expectations include, but are not limited to, the businesses of Bank of Marin Bancorp and/or American River Bankshares may not be integrated successfully or such integration may be more difficult, time-consuming or costly than expected; expected revenue synergies and cost savings from the acquisition may not be fully realized or realized within the expected time frame; revenues following the merger may be lower than expected; customer and employee relationships and business operations may be disrupted by the acquisition; the ability to obtain required regulatory and shareholder approvals, and the ability to complete the acquisition on the expected timeframe may be more difficult, time-consuming or costly than expected; natural disasters (such as wildfires and earthquakes), our borrowers' actual payment performance as loan deferrals related to the COVID-19 pandemic expire, changes to statutes, regulations, or regulatory policies or practices as a result of, or in response to COVID-19, including the potential adverse impact of loan modifications and payment deferrals implemented consistent with recent regulatory guidance, general economic conditions, economic uncertainty in the United States and abroad, changes in interest rates, deposit flows, real estate values, costs or effects of acquisitions, competition, changes in accounting principles, policies or guidelines, 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), 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 Bancorp's operations, pricing, products and services. These and other important factors are detailed in various securities law filings made periodically by Bancorp, copies of which are available from Bancorp without charge. 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 after the date of this presentation or to reflect the occurrence of unanticipated events.

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Strategic Rationale

Strategic Rationale

Financially

Attractive

• Expands combined company footprint across the Greater Bay Area, Sacramento and Amador regions
• • Creates a $4.0 billion bank that is well positioned to become the preeminent business bank serving Northern California
  • Increases efficiency and spreads costs across a diversified geographic footprint
  • Increased capital enhances lending capabilities for American River Bank customers
• Builds immediate scale in highly attractive Northern California markets
• • Combined company would be one of the largest community banks by market capitalization headquartered in Northern California(1)(2)
• American River Bank is a high quality, relationship-based business bank
• • Community-focusedbank headquartered in the Greater Sacramento region
  • Total assets of $916 million, total loans of $475 million and total deposits of $789 million
  • Disciplined credit and risk management cultures
• Aligned loan and deposit strategies allows for a seamless integration of business models
• • Enhances already strong core deposit base
• Similar cultures committed to providing exceptional client service and dedication to local communities
• 14.2% accretive to 2022 earnings per share (fully phased-in cost savings)
• 3.9% tangible book value dilution with a 3.5 year earnback
• >15% internal rate of return
• Robust pro forma capital ratios

(1)	Includes banks with less than $10 billion in assets headquartered north of Ventura, Los Angeles, and San Bernardino counties.	3
(2)	Market data as of 4/16/2021.

American River Bankshares (NASDAQ: AMRB) Overview

Branch Locations

Financial Highlights as of 3/31/2021

• AMRB (10) AMRB HQ

Company Highlights

• Headquarters: Rancho Cordova, CA
• Strong NorCal presence: 10 full-service branches providing business banking services in Sacramento, Amador, Sonoma, and Placer counties
• Organic Growth in Current Markets: Low cost of core deposits, robust sales culture, and an extraordinary client experience
• Lending Expertise: Commercial real estate, small business ($1-$50mm), wholesalers/manufacturers, professionals, and property managers
• Relationship Banking: Customized financial services for businesses, business owners, their families and employees

Deposit Market Share by County

	County	County	Active	Deposit		Market
	Population	Median HHI	Branches	Rank	Deposits	Share
County	(actual)	($actual)	(#)	(#)	($mm)	(%)
Sacramento	1,564,478	$74,806	4	12	$437.3	1.05%
Amador	39,554	$66,656	3	3	$133.7	16.45
Sonoma	492,770	$90,481	2	14	$103.5	0.63
Placer	402,773	$95,803	1	21	$67.2	0.55

Balance Sheet ($mm)

Total Assets	$	916.1
Total Loans		475.4
Total Deposits		788.6
Tangible Common Equity		76.6
Profitability / Rates for the Quarter Ended 3/31/2021 (%)
Net Income ($000s)	$	2,647
Return on Average Assets		1.21
Return on Average Tangible Common Equity		14.00
Net Interest Margin		3.58
Efficiency Ratio (FTE)		52.3
Yield on Total Loans		4.92
Cost of Total Deposits		0.09
Balance Sheet Ratios / Capital (%)
Total Loans / Deposits		60.3
TCE / TA		8.51
Leverage Ratio		8.46
Tier 1 Risk-based Capital Ratio		15.47
Total Risk-based Capital Ratio		16.72
Asset Quality (%)
Nonperforming Loans / Total Loans		0.00
Net (Recoveries) Chargeoffs / Average Loans		(0.06)
Allowance for Loans Losses / Total Loans (Excluding PPP Loans)		1.60
Market information as of 4/16/21
Stock Price ($)	$	16.35
Market Cap ($mm)(1)	$	97.5
Price / Tangible Book Value per Share (x)(1)		1.27x
Price / 2022 EPS (x)(2)		12.5x
Dividend Yield (%)		1.71

Source: Company documents, S&P Global, FactSet, and FDIC Summary of Deposits.	4
Note: Deposit market share data as of 6/30/2020. Excludes non-retail deposits.
(1)	Based on common shares outstanding of 5,962,466 as of 3/31/2021.
(2)	Consensus estimates per FactSet.

Greater Sacramento Region Market Highlights

• American River Bank expands BMRC's presence into a growing
  Greater Sacramento Region
• • The Greater Sacramento region has a population of ~2.6 million
  • The population of Sacramento-Roseville-Folsom MSA is expected to grow 3.6% from 2021 to 2026, compared to 2.6% for the state of California and 2.9% nationwide
  • Additionally, household income is expected to grow 13.0% from 2021 to 2026, compared to only 9.0% nationwide
• In the last year, the region has been ranked the top migration destination for people looking to relocate, driven in part by newly remote workers seeking a more affordable lifestyle while still accessible to everything Northern California has to offer
• • Ample amount of available low-rise,campus-style office space for companies to open satellite offices to follow employees migrating into the region
  • Increasingly attractive market for companies seeking educated, young professionals from a number of universities including
    UC Davis, Sacramento State University, and University of the Pacific
• Sacramento's Downtown and Midtown areas have been experiencing a renaissance and reinvigoration
• • $6 billion invested in new development since the opening of the Golden 1 Center in 2016
  • New residential and hospitality projects are poised to transform
    Sacramento's urban core into a true live/work/play destination

Source: S&P Global, California Credit Union League, Bureau of Labor Statistics, Colliers International, and Greater Sacramento Economic Council.	5