Columbia Banking (COLB) EVP reports share forfeiture and RSU tax withholding

Rhea-AI Filing Summary

Columbia Banking System executive Aaron James Deer, EVP Chief Strategy/Innovation Officer, reported two stock-related transactions in Columbia Banking, Inc. common stock. On January 20, 2026, he forfeited 325 shares at a stated price of $0, tied to performance-based restricted stock units granted on February 21, 2023, after a total shareholder return target was not met. On the same date, 776 shares were withheld at $28.35 per share to cover tax obligations arising from the vesting of previously issued restricted stock units. After these transactions, Deer directly owned 40,945 shares of Columbia Banking common stock.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Deer Aaron James

Role EVP Chief Strategy/Innov Offcr

Type	Security	Shares	Price	Value
Disposition	Common Stock	325	$0.00	--
Tax Withholding	Common Stock	776	$28.35	$22K

Holdings After Transaction: Common Stock — 41,721 shares (Direct)

Footnotes (1)

1. Shares forfeited pursuant to the terms of the performance restricted stock units granted on February 21, 2023 and reported on the reporting person's Form 4 filed on February 21, 2023 (in accordance with Rule 16b-3(e)) due to the issuer's total shareholder return performance target not being met at target. Represents withholding of shares of common stock to satisfy the reporting person's tax withholding obligations in connection with the vesting of previously issued restricted stock units.

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
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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^*

Deer Aaron James

(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 Chief Strategy/Innov Offcr

3. Date of Earliest Transaction (Month/Day/Year)
01/20/2026

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	01/20/2026		D		325(1)	D	$0	41,721	D
Common Stock	01/20/2026		F		776(2)	D	$28.35	40,945	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 forfeited pursuant to the terms of the performance restricted stock units granted on February 21, 2023 and reported on the reporting person's Form 4 filed on February 21, 2023 (in accordance with Rule 16b-3(e)) due to the issuer's total shareholder return performance target not being met at target.

2. Represents withholding of shares of common stock to satisfy the reporting person's tax withholding obligations in connection with the vesting of previously issued restricted stock units.

Remarks:

	/s/ Andrea M. Newburn, Attorney-in-fact	01/22/2026
	** 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 activity did COLB executive Aaron James Deer report?

EVP Chief Strategy/Innovation Officer Aaron James Deer reported forfeiting 325 shares of Columbia Banking common stock and having 776 shares withheld to satisfy tax obligations related to vesting restricted stock units, both dated January 20, 2026.

Why were 325 COLB shares forfeited by the executive?

The 325 shares were forfeited under the terms of performance restricted stock units granted on February 21, 2023, because the issuer’s total shareholder return performance target was not achieved at target.

What does the 776-share transaction in COLB stock represent?

The 776 shares of Columbia Banking common stock were withheld at $28.35 per share to cover tax withholding obligations in connection with the vesting of previously issued restricted stock units.

How many COLB shares does Aaron James Deer own after these transactions?

Following the reported transactions on January 20, 2026, Aaron James Deer directly owned 40,945 shares of Columbia Banking, Inc. common stock.

Are the reported COLB transactions direct or indirect holdings?

Both reported positions are shown as direct (D) ownership of Columbia Banking common stock by Aaron James Deer, with no indirect ownership entity noted.

Do these COLB insider transactions involve open-market buying or selling?

No open-market trades are indicated. One transaction reflects forfeiture of shares tied to performance criteria, and the other reflects share withholding for taxes on vesting restricted stock units.