Lakely Brock 4

What Happened
Lakely Brock, EVP and Chief Accounting Officer of Columbia Banking System, had 846 restricted stock units vest and converted into 846 common shares on March 13, 2026 (reported as an exercise/conversion). The vested shares are valued at $26.23 each, totaling $22,191. On the same date Brock sold 211 of those shares in an open-market transaction at $26.23 per share, receiving $5,535. Overall the filing shows a net increase of 635 shares from the conversion minus the sale.

Key Details

• Transaction date: 2026-03-13. Reporting filed: 2026-03-17 (timely).
• Conversion: 846 shares (derivative conversion/exercise) at $26.23 — value $22,191.
• Sale: 211 shares sold open market at $26.23 — proceeds $5,535 (transaction code S).
• Additional filing line: 846 shares listed as disposed at $0.00 — reflects the RSU-to-share conversion bookkeeping.
• Shares owned after the transactions: not disclosed in the Form 4 filing.
• Footnote: 2,537 RSUs were granted on Feb 25, 2025 and vest in three annual installments beginning March 13, 2026 (846 shares represents one installment).

Context
The filing records a conversion of vested RSUs into common stock (a non-cash issuance) and a partial sale of those shares. The Form 4 does not state why 211 shares were sold; partial sales after RSU vesting are commonly used for tax withholding or liquidity, but the filing gives no specific reason. The report was filed within the required timeframe.