COLB (COLB) EVP uses 1,036 shares for tax withholding in Form 4

Rhea-AI Filing Summary

COLUMBIA BANKING SYSTEM, INC. executive Kumi Yamamoto Baruffi, EVP General Counsel and Corporate Secretary, reported a Form 4 transaction involving company common stock. The filing shows a tax-withholding disposition of 1,036 shares of common stock at a price of $31.49 per share on February 15, 2026. After this transaction, the reporting person directly owned 54,070 shares of common stock.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider BARUFFI KUMI YAMAMOTO

Role EVP General Counsel, Corp Sec

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	1,036	$31.49	$33K

Holdings After Transaction: Common Stock — 54,070 shares (Direct)

Footnotes (1)

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)
02/15/2026

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	02/15/2026		F		1,036	D	$31.49	54,070	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:

Remarks:

	/s/ Andrea M. Newburn, Attorney-in-fact	02/18/2026
	** 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 transaction did COLB executive Kumi Yamamoto Baruffi report?

Kumi Yamamoto Baruffi reported a tax-withholding disposition of 1,036 shares of COLUMBIA BANKING SYSTEM common stock. The transaction used existing shares to cover tax obligations rather than representing an open-market purchase or sale.

What was the share price in the reported COLB Form 4 transaction?

The reported tax-withholding disposition occurred at a price of $31.49 per share. This price applies to the 1,036 shares of COLUMBIA BANKING SYSTEM, INC. common stock used to satisfy the tax liability in the transaction.

How many COLB shares does Kumi Yamamoto Baruffi hold after the transaction?

Following the reported transaction, Kumi Yamamoto Baruffi directly owned 54,070 shares of COLUMBIA BANKING SYSTEM common stock. This post-transaction balance reflects the shares remaining after 1,036 shares were disposed of for tax-withholding purposes.

What does transaction code F mean in the COLB Form 4 filing?

Transaction code F indicates payment of an exercise price or tax liability by delivering securities. In this filing, 1,036 COLB common shares were disposed of as a tax-withholding transaction rather than an ordinary market sale of stock.

Is the COLB Form 4 transaction a buy or sell of shares?

The Form 4 describes a tax-withholding disposition, categorized as a dispose transaction. Shares were delivered to satisfy tax obligations, and the filing does not classify the activity as a typical open-market buy or sell.