BARUFFI KUMI YAMAMOTO 4

What Happened
Kumi Yamamoto, EVP General Counsel and Corporate Secretary of Columbia Banking System (COLB), received 5,093 shares on Feb 2, 2026 as the vesting of performance-based restricted stock units (RSUs). The shares were valued at $29.69 each for a total grant value of $151,211. To satisfy tax withholding obligations, 2,110 of those shares (valued at $29.69 each, $62,646 total) were withheld by the company.

Key Details

• Transaction date: February 2, 2026. Report filed February 4, 2026 (appears timely).
• Award: 5,093 shares granted @ $29.69 (total $151,211) — code A (award/grant).
• Tax withholding: 2,110 shares withheld @ $29.69 (total $62,646) — code F (tax withholding/ payment).
• Shares owned after the transaction: not specified in the provided filing.
• Footnotes:
  • The 5,093 shares vested under performance RSUs originally granted Feb 21, 2023, based on Columbia’s relative return on tangible common equity for fiscal years 2023–2025 versus an approved peer group.
  • The 2,110-share disposition represents share withholding to satisfy the reporting person's tax withholding obligations.

Context
This was a vesting of performance-based equity, not an open-market purchase or voluntary sale. Withholding of shares to cover taxes is a routine administrative action and does not necessarily indicate a change in the insider’s view of the company.