X0306 4/A 2022-01-19 2022-01-25 0001499422 RBB Bancorp RBB 0001711522 Kao James 1055 WILSHIRE BLVD SUITE 1200 LOS ANGELES CA 90017 1 Common Stock, No Par Value 413876 D Restricted Stock Units 0.0000 Restricted Stock Units 1100 1100 D These restricted stock units vest in two equal annual installments beginning one year after the 01/19/2022 date of grant. There will be no expiration date once restricted stock units vest. Amending James Kao's vesting period of his granted 1,100 restricted stock units that will vest in two equal annual installments on 01/19/2023 and 01/19/2024. /s/ James Kao 2022-02-17