EXHIBIT 16 November 6, 2000 Office of the Chief Accountant Securities and Exchange Commission 450 Fifth Street, North West Washington, D.C. 20549 Dear Sir/Madam: We have read paragraphs one (1) and two (2) of Item 4 included in the Form 8- K/A dated November 6, 2000 of Pacific Mercantile Bancorp to be filed with the Securities and Exchange Commission and are in agreement with the statements contained therein. Very truly yours, /s/ Arthur Andersen LLP Arthur Andersen LLP cc: Mr. Dan Erickson, CFO, Pacific Mercantile Bancorp