X0306 4 2020-08-11 false 0001109546 PACIFIC MERCANTILE BANCORP PMBC 0001561111 Deutsch James F. C/O PATRIOT FINANCIAL PARTNERS, L.P. 4 RADNOR CORP. CENT., 100 MATSONFORD RD SUITE 210 RADNOR PA 19087 true false false true See Remarks (1) Common Stock 2020-08-11 4 P false 292500.00 3.50 A 2485708.00 I By Patriot Financial Partners III, L.P. Non-Voting Common Stock 1467155.00 I By Patriot Financial Partners III, L.P. /s/Curt A. Christianssen, attorney in fact for James F. Deutsch 2020-08-12