Sec Form 4 Filing - Liu Vincent @ RBB Bancorp - 2021-08-31

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5

1. Name and Address of Reporting Person Liu Vincent 2. Issuer Name and Ticker or Trading Symbol RBB Bancorp [ RBB] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) EVP (Last) (First) (Middle) 1055 WILSHIRE BLVD, SUITE 1200 3. Date of Earliest Transaction (MM/DD/YY) 08/31/2021 (Street) LOS ANGELES, CA90017 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock, No Par Value 08/31/2021 M 94,172 A $ 11.1498 165,335 D Common Stock, No Par Value 08/31/2021 S 94,172 ( 2 ) D $ 25.5 ( 3 ) 71,163 D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Option (right to buy) $ 11.1498 08/31/2021 M 94,172 ( 1 ) 01/01/2023 Common Stock 94,172 $ 11.1498 0 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Liu Vincent 1055 WILSHIRE BLVD SUITE 1200 LOS ANGELES, CA90017 EVP Signatures /s/ Vincent Liu 09/01/2021 Signature of Reporting Person Date

Explanation of Responses:

( 1 )These options vest in three equal annual installments beginning one year after the 01/01/2013 date of grant. ( 2 )Exercise of reporting person's stock options that would otherwise expire 01/01/2023, of which shares were sold to pay the exercise price, to cover withholding taxes, and to pay broker fees and commissions, pursuant to a broker-assisted cashless exercise and sale. ( 3 )Price reflected is the weighted-average sale price for shares, which were sold in multiple transactions. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or any staff member of the Securities and Exchange Commission, upon request, information regarding the number of shares sold at each separate price.

Remarks: Vincent Liu is reporting a cashless exercise and sale of 94,172 shares.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.