InsiderTrades

Form 4 for COLB COLUMBIA BANKING SYSTEM, INC.

Accepted 2026-03-17 00:00:00 ET · period of report 2026-03-13 · accession 0001796657-26-000005 · 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 Merrywell Christopher Senior Executive VP M - OptEx $26.23 +5,013 46.0K +12% +$131.5K
D 2026-03-17 2026-03-13 COLB Merrywell Christopher Senior Executive VP F - Tax $26.23 -1,973 44.1K -4% -$51.8K
D 2026-03-17 2026-03-13 COLB Merrywell Christopher Senior Executive VP M - OptEx $0.00 -5,013 51.3K -9% $0

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#TableSecurityDateCodeA/DSharesPriceOwned afterOwnExercise / expiryUnderlyingFootnotes
1 Common Common Stock 2026-03-13 M A 5,013 $26.23 46,040 D — —
2 Common Common Stock 2026-03-13 F D 1,973 $26.23 44,067 D — —
3 Derivative Restricted Stock Unit 2026-03-13 M D 5,013 $0.00 51,291 D — · — to — 5,013 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 15,037 Restricted Stock Units, which vest in three annual installments beginning on March 13, 2026.