X0508 4 2024-02-21 0001499422 RBB Bancorp RBB 0001185980 LEE JOHNNY C 1055 WILSHIRE BLVD SUITE 1200 LOS ANGELES CA 90017 1 Pres / Chief Banking Officer 0 Common Stock, No Par Value 0 D Restricted Stock Units 0.0000 Restricted Stock Units 16500 16500 D Restricted Stock Units 0.0000 Restricted Stock Units 3294 3294 D These restricted stock units vest in three equal annual installments beginning one year after the 07/20/2023 date of grant. There will be no expiration date once restricted stock units vest. These restricted stock units vest in three equal annual installments beginning one year after the 02/21/2024 date of grant. Johnny Lee was granted 3,294 restricted stock units that will vest in three equal annual installments on 02/21/2025, 02/21/2026, and 02/21/2027. /s/ Johnny Lee 2024-02-22