X0609 4 2026-05-04 0001499422 RBB Bancorp RBB 0001711919 Morris David Richard false 1055 WILSHIRE BLVD SUITE 1200 LOS ANGELES CA 90017 1 0 Common Stock, No Par Value 2026-05-04 4 S 0 4500 23.90 D 43422 D Restricted Stock Units 0.0000 Common Stock 2225 2225 D Restricted Stock Units 0.0000 Common Stock 3164 3164 D There will be no expiration date once restricted stock units vest. These remaining restricted stock units vest on 02/21/2027. These remaining restricted stock units vest on 03/20/2027. 4,500 shares were sold on 5/04/2026. /s/ David Morris 2026-05-05