[Form 4] RBB Bancorp Insider Trading Activity

Rhea-AI Filing Summary

RBB Bancorp Chief Accounting Officer Diana Hanson reported her updated equity holdings, with no explicit buys or sells. She now directly holds 492 shares of Common Stock. She also holds Restricted Stock Units (RSUs) that will be settled in Common Stock as they vest over time.

One RSU grant covers 1,255 underlying shares of Common Stock, vesting in three equal annual installments on 08/19/2026, 08/19/2027 and 08/19/2028. Another RSU grant covers 2,300 underlying shares, vesting in four equal annual installments beginning one year after the 05/13/2026 grant date. Footnotes clarify that vested RSUs have no expiration date and that grants of RSUs will be settled in Common Stock.

Insider Trade Summary

3 transactions reported

Mixed 3 txns

Insider Hanson Diana

Role Chief Accounting Officer

Type	Security	Shares	Price	Value
holding	Restricted Stock Units	--	--	--
holding	Restricted Stock Units	--	--	--
holding	Common Stock, No Par Value	--	--	--

Holdings After Transaction: Restricted Stock Units — 2,300 shares (Direct, null); Common Stock, No Par Value — 492 shares (Direct, null)

Footnotes (1)

1. There will be no expiration date once restricted stock units vest. These remaining restricted stock units vest in three equal annual installment on 08/19/2026, 08/19/2027 and 08/19/2028 date of grant. The Form 4 has been updated to clarify that grants of RSUs will be settled in Common Stock. These restricted stock units vest in four equal annual installments beginning one year after the 05/13/2026 date of grant.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

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
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

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

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Hanson Diana

(Last) (First) (Middle)

1055 WILSHIRE BLVD

SUITE 1200

(Street)

LOS ANGELES CALIFORNIA 90017

(City) (State) (Zip)

UNITED STATES

(Country)

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)
	Chief Accounting Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
05/13/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	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								492	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 (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	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 (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (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: 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
Restricted Stock Units	$0.0000							(2)	(1)	Common Stock(3)	2,300		2,300	D
Restricted Stock Units	$0.0000							(4)	(1)	Common Stock	1,255		1,255	D

Explanation of Responses:

1. There will be no expiration date once restricted stock units vest.

2. These remaining restricted stock units vest in three equal annual installment on 08/19/2026, 08/19/2027 and 08/19/2028 date of grant.

3. The Form 4 has been updated to clarify that grants of RSUs will be settled in Common Stock.

4. These restricted stock units vest in four equal annual installments beginning one year after the 05/13/2026 date of grant.

Remarks:

Restricted Stock Units (RSUs) were granted on May 13, 2026.

	/s/ Diana Hanson	05/15/2026
	** Signature of Reporting Person	Date
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.
* Form 4: SEC 1474 (03-26)