InsiderTrades

Form 4 for COLB COLUMBIA BANKING SYSTEM, INC.

Accepted 2026-03-17 00:00:00 ET · period of report 2026-03-13 · accession 0001550429-26-000002 · SEC index · Original document

Summary rows

Aggregated the way they appear in lists: one row per insider, transaction code and security table.

X Filed Traded Ticker Insider Title Type Price Qty Owned ΔOwn Value
D 2026-03-17 2026-03-13 COLB Stein Clint COB, CEO, Pres, Dir F - Tax $26.23 -7,151 151.6K -5% -$187.6K
D 2026-03-17 2026-03-13 COLB Stein Clint COB, CEO, Pres, Dir M - OptEx $26.23 +18.2K 158.7K +13% +$476.6K
D 2026-03-17 2026-03-13 COLB Stein Clint COB, CEO, Pres, Dir M - OptEx $0.00 -18.2K 167.0K -10% $0

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#TableSecurityDateCodeA/DSharesPriceOwned afterOwnExercise / expiryUnderlyingFootnotes
1 Common Common Stock 2026-03-13 F D 7,151 $26.23 151,584 D — —
2 Common Common Stock 2026-03-13 M A 18,171 $26.23 158,735 D — —
3 Derivative Restricted Stock Unit 2026-03-13 M D 18,171 $0.00 166,984 D — · — to — 18,171 Common Stock (F1) Restricted Stock Units convert into common stock on a one-for-one basis. On February 25, 2025, the reporting person was granted 54,511 Restricted Stock Units, which vest in three annual installments beginning on March 13, 2026.