Aaron James Deer - 13 Mar 2026 Form 4 Insider Report for COLUMBIA BANKING SYSTEM, INC. (COLB)

Role
EVP Chief Strategy/Innov Offcr
Signature
/s/ Andrea M. Newburn, Attorney-in-fact
Issuer symbol
COLB
Transactions as of
13 Mar 2026
Net transactions value
$0
Form type
4
Filing time
17 Mar 2026, 20:27:37 UTC
Previous filing
02 Mar 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Deer Aaron James EVP Chief Strategy/Innov Offcr C/O COLUMBIA BANKING SYSTEM, INC., 1301 A STREET, TACOMA /s/ Andrea M. Newburn, Attorney-in-fact 17 Mar 2026 0001810107

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction COLB Common Stock Options Exercise +1,567 +3.8% $26.23* 42,492 13 Mar 2026 Direct
transaction COLB Common Stock Tax liability -617 -1.5% $26.23* 41,875 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 -1,567 -18% $0.000000* 7,133 13 Mar 2026 Common Stock 1,567 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 4,699 Restricted Stock Units, which vest in three annual installments beginning on March 13, 2026.