Brock Lakely - 13 Mar 2026 Form 4 Insider Report for COLUMBIA BANKING SYSTEM, INC. (COLB)

Role
EVP, Chief Accounting Officer
Signature
/s/ Andrea M. Newburn, Attorney-in-fact
Issuer symbol
COLB
Transactions as of
13 Mar 2026
Net transactions value
-$5,535
Form type
4
Filing time
17 Mar 2026, 20:31:01 UTC
Previous filing
02 Mar 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Lakely Brock EVP, Chief Accounting Officer C/O COLUMBIA BANKING SYSTEM, INC., 1301 A STREET, TACOMA /s/ Andrea M. Newburn, Attorney-in-fact 17 Mar 2026 0001740374

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction COLB Common Stock Options Exercise +846 +8.1% $26.23* 11,315 13 Mar 2026 Direct
transaction COLB Common Stock Sale $5,535 -211 -1.9% $26.23 11,104 13 Mar 2026 Direct

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction COLB Restricted Stock Unit Options Exercise -846 -7.9% $0.000000* 9,810 13 Mar 2026 Common Stock 846 Direct F1
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Restricted Stock Units convert into common stock on a one-for-one basis. On February 25, 2025, the reporting person was granted 2,537 Restricted Stock Units, which vest in three annual installments beginning on March 13, 2026.