Columbia Banking (COLB) EVP reports 5,093-share award and tax withholding

Rhea-AI Filing Summary

Columbia Banking System executive Kumi Yamamoto Baruffi reported routine equity compensation activity. On February 2, 2026, she acquired 5,093 shares of common stock at $29.69 per share from performance-based restricted stock units granted on February 21, 2023. These units vested based on the company’s relative return on tangible common equity for fiscal years 2023–2025 versus a Compensation Committee–approved peer group. To cover tax withholding on the vested shares, 2,110 shares were withheld at $29.69 per share. After these transactions, she directly owns 55,106 shares of Columbia Banking, Inc. common stock.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider BARUFFI KUMI YAMAMOTO

Role EVP General Counsel, Corp Sec

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	5,093	$29.69	$151K
Tax Withholding	Common Stock	2,110	$29.69	$63K

Holdings After Transaction: Common Stock — 57,216 shares (Direct)

Footnotes (1)

1. Shares granted pursuant to the terms of the performance restricted stock units granted on February 21, 2023, which vested on February 2, 2026 based on to the issuer's relative return on tangible common equity for fiscal years 2023-2025 compared to a Compensation Committee approved group of peers. Represents withholding of shares of common stock to satisfy the reporting person's tax withholding obligations in connection with the shares granted pursuant to the terms of the performance restricted stock units vesting.

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^*

BARUFFI KUMI YAMAMOTO

(Last) (First) (Middle)

C/O COLUMBIA BANKING SYSTEM, INC.

1301 A STREET

(Street)

TACOMA WA 98402

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
COLUMBIA BANKING SYSTEM, INC. [ COLB ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP General Counsel, Corp Sec

3. Date of Earliest Transaction (Month/Day/Year)
02/02/2026

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

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

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

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	02/02/2026		A		5,093(1)	A	$29.69	57,216	D
Common Stock	02/02/2026		F		2,110(2)	D	$29.69	55,106	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

Explanation of Responses:

1. Shares granted pursuant to the terms of the performance restricted stock units granted on February 21, 2023, which vested on February 2, 2026 based on to the issuer's relative return on tangible common equity for fiscal years 2023-2025 compared to a Compensation Committee approved group of peers.

2. Represents withholding of shares of common stock to satisfy the reporting person's tax withholding obligations in connection with the shares granted pursuant to the terms of the performance restricted stock units vesting.

Remarks:

	/s/ Andrea M. Newburn, Attorney-in-fact	02/04/2026
	** 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.

FAQ

What insider transactions did COLB report for Kumi Yamamoto Baruffi on February 2, 2026?

On February 2, 2026, EVP and General Counsel Kumi Yamamoto Baruffi received 5,093 COLB common shares from vested performance restricted stock units and had 2,110 shares withheld to satisfy tax obligations related to that vesting, both recorded at $29.69 per share.

How many Columbia Banking (COLB) shares does Kumi Yamamoto Baruffi own after the latest Form 4?

After the reported grant and tax withholding on February 2, 2026, EVP and General Counsel Kumi Yamamoto Baruffi directly owns 55,106 shares of Columbia Banking, Inc. common stock, according to the beneficial ownership figure disclosed in the Form 4 filing.

What triggered the 5,093-share grant to Columbia Banking EVP Kumi Yamamoto Baruffi?

The 5,093-share grant resulted from performance restricted stock units awarded on February 21, 2023, which vested on February 2, 2026 based on Columbia Banking’s relative return on tangible common equity for fiscal years 2023–2025 versus a Compensation Committee–approved peer group.

Why were 2,110 COLB shares reported as disposed of for Kumi Yamamoto Baruffi?

The 2,110 COLB shares were withheld to satisfy Kumi Yamamoto Baruffi’s tax withholding obligations tied to the vesting of her performance restricted stock units, rather than an open-market sale, with the shares valued at $29.69 each for this tax-related transaction.

What role does Kumi Yamamoto Baruffi hold at Columbia Banking (COLB)?

Kumi Yamamoto Baruffi serves as Executive Vice President, General Counsel, and Corporate Secretary of Columbia Banking, Inc., as indicated in the Form 4, and is therefore classified in the filing as an officer of the issuer rather than a director or 10% owner.

How were performance conditions measured for the COLB restricted stock units that vested in 2026?

The performance restricted stock units that vested on February 2, 2026 were tied to Columbia Banking’s relative return on tangible common equity over fiscal years 2023–2025, measured against a peer group approved by the company’s Compensation Committee, according to the Form 4 explanation.