Director boosts Columbia Banking (COLB) deferred phantom stock holdings

Rhea-AI Filing Summary

Columbia Banking, Inc. director Luis Machuca reported additional deferred compensation phantom stock units tied to the company’s common stock. On 12/03/2025, 65 phantom stock units were accrued at $28.17, bringing his indirect deferred compensation balance to 47,182 units. On 02/04/2026, a further 562 phantom stock units were accrued at $31.12, increasing the balance to 47,744 units, all held indirectly through a deferred compensation arrangement. One accrual was executed by the plan administrator without his request, and all phantom stock will be paid under the plan’s terms after his employment ends.

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^*

MACHUCA LUIS

(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)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
12/03/2025

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

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
Deferred Compensation Phantom Stock	(1)	12/03/2025		A		65		(1)	(1)	Common	65	$28.17	47,182	I	Deferred Compensation
Deferred Compensation Phantom Stock	(2)	02/04/2026		A		562		(2)	(2)	Common	562	$31.12	47,744	I	Deferred Compensation

Explanation of Responses:

1. The deferred compensation plan phantom stock was accrued under the Registrant's deferred compensation plan and the result of a transaction by the plan administrator that the reporting person did not request and that they were not aware of at the time of the transaction. The phantom stock will be paid in accordance with the terms of the deferred compensation plan following the end of the reporting person's employment with the Registrant.

2. The deferred compensation plan phantom stock was accrued under the Registrant's deferred compensation plan and will be paid in accordance with the terms of the deferred compensation plan following the end of the reporting person's employment with the Registrant.

Remarks:

	/s/ Andrea M. Newburn, Attorney-in-fact	02/05/2026
	** 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 Luis Machuca report at Columbia Banking (COLB)?

Director Luis Machuca reported accruals of deferred compensation phantom stock units linked to Columbia Banking’s common stock. He added 65 units on December 3, 2025 and 562 units on February 4, 2026, increasing his indirect deferred compensation balance to 47,744 units.

What is deferred compensation phantom stock in the COLB Form 4 filing?

Deferred compensation phantom stock represents units credited under Columbia Banking’s deferred compensation plan that track the value of common shares. These units are bookkeeping entries, not actual shares, and will be paid according to plan terms after the director’s employment with the company ends.

Were Luis Machuca’s COLB phantom stock transactions open-market purchases?

No, the Form 4 shows phantom stock accruals under Columbia Banking’s deferred compensation plan, not open-market trades. One transaction was carried out by the plan administrator without Machuca’s request, reflecting routine plan administration rather than discretionary insider stock buying.

How many COLB phantom stock units does Luis Machuca now indirectly hold?

After the reported transactions, Luis Machuca indirectly holds 47,744 deferred compensation phantom stock units tied to Columbia Banking’s common stock. These units accumulated through plan accruals at prices of $28.17 and $31.12, and remain subject to the plan’s payout conditions.

How are the COLB deferred compensation phantom stock units valued in the Form 4?

The phantom stock units are shown with reference prices per unit, $28.17 and $31.12, corresponding to Columbia Banking’s common stock value at the time of accrual. These prices help quantify the credited compensation within the company’s deferred compensation plan framework.