Columbia Banking director sells 10,522 shares

A footnote clarifies that 10,522 shares previously reported as indirectly owned were directly beneficially owned.

Available on EDGAR 10/30/2026 - 06:48 PM EDT Accepted by SEC EDGAR 10/30/2026 - 06:48 PM EDT Learn about SEC filing dates

Rhea-AI Filing Summary

Columbia Banking System, Inc. (COLB) director Steven R. Gardner reported selling 10,522 common shares in seven direct transactions on October 29, 2026. The seven reported per-share prices were $31.2150, $31.2200, $31.2250, $31.2300, $31.2350, $31.2400 and $31.2450.

A separate holding entry reports 559,848 shares held indirectly by a family trust. A footnote states that 10,522 shares previously reported as indirectly owned were directly beneficially owned.

Insider Trade Summary

Net Seller: 10,522 shares

Net Sell 7 txns

Insider GARDNER STEVEN R

Role Director

Sold 10,522 shs ($329K)

Share of Position Sold 80.3%

Type	Security	Shares	Price	Value
Sale	Common Stock	484	$31.215	$15K
Sale	Common Stock	100	$31.22	$3K
Sale	Common Stock	5,012	$31.225	$156K
Sale	Common Stock	200	$31.23	$6K
Sale	Common Stock	2,151	$31.235	$67K
Sale	Common Stock	322	$31.24	$10K
Sale	Common Stock	2,253	$31.245	$70K
Holding	Common Stock F1	--	--	--

Holdings After Transaction: Common Stock — 2,577 shares (Direct); Common Stock — 559,848 shares (Indirect, by family trust)

Holdings Before and After: Common Stock, 13,099 to 2,577 shares (Direct)

Footnotes (1)

1. F1. 10,522 shares of the Issuer's common stock were previously inadvertently reported as indirectly owned by the reporting person and are directly beneficially owned by the reporting person.

Key Figures

Common shares sold: 10,522 shares Sale: 484 shares at $31.2150 per share Sale: 100 shares at $31.2200 per share +5 more

8 metrics

Common shares sold 10,522 shares Seven direct sales on October 29, 2026

Sale 484 shares at $31.2150 per share October 29, 2026

Sale 100 shares at $31.2200 per share October 29, 2026

Sale 5,012 shares at $31.2250 per share October 29, 2026

Sale 200 shares at $31.2300 per share October 29, 2026

Sale 2,151 shares at $31.2350 per share October 29, 2026

Sale 322 shares at $31.2400 per share October 29, 2026

Sale 2,253 shares at $31.2450 per share October 29, 2026

Key Terms

directly beneficially owned, indirectly owned, family trust

3 terms

directly beneficially owned regulatory

"directly beneficially owned by the reporting person"

indirectly owned regulatory

"previously reported as indirectly owned"

family trust regulatory

"by family trust"

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

How many COLB shares did director Steven R. Gardner sell?

Steven R. Gardner reported selling 10,522 shares across seven direct transactions on October 29, 2026. The per-share prices were $31.2150, $31.2200, $31.2250, $31.2300, $31.2350, $31.2400 and $31.2450. No Rule 10b5-1 plan is reported.

AI-generated analysis. How Rhea-AI works. Not financial advice.

Form 4 Insider Transactions: What Each Field Means →

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

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^*

GARDNER STEVEN R

(Last) (First) (Middle)

C/O COLUMBIA BANKING SYSTEM, INC.

1301 A STREET

(Street)

TACOMA WASHINGTON 98402

(City) (State) (Zip)

UNITED STATES

(Country)

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)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
10/29/2026

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	10/29/2026		S		484	D	$31.215	12,615	D
Common Stock	10/29/2026		S		100	D	$31.22	12,515	D
Common Stock	10/29/2026		S		5,012	D	$31.225	7,503	D
Common Stock	10/29/2026		S		200	D	$31.23	7,303	D
Common Stock	10/29/2026		S		2,151	D	$31.235	5,152	D
Common Stock	10/29/2026		S		322	D	$31.24	4,830	D
Common Stock	10/29/2026		S		2,253	D	$31.245	2,577	D
Common Stock								559,848(1)	I	by family trust

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. 10,522 shares of the Issuer's common stock were previously inadvertently reported as indirectly owned by the reporting person and are directly beneficially owned by the reporting person.

Remarks:

	/s/ Andrea M. Newburn, Attorney-in-fact	10/30/2026
	** 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)