| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| Merrywell Christopher | Senior Executive VP | C/O COLUMBIA BANKING SYSTEM, INC., 1301 A STREET, TACOMA | /s/ Andrea M. Newburn, Attorney-in-fact | 22 Jan 2026 | 0001796657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | COLB | Common Stock | Disposed to Issuer | $0 | -1,560 | -3.6% | $0.000000 | 41,832 | 20 Jan 2026 | Direct | F1 |
| transaction | COLB | Common Stock | Tax liability | $99,112 | -3,496 | -8.4% | $28.35 | 38,336 | 20 Jan 2026 | Direct | F2 |
| Id | Content |
|---|---|
| F1 | 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. |
| F2 | 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. |