Columbia Banking System Inc
Ownership
Ownership Structure
Who owns Columbia Banking System Inc (COLB)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 99.1% of the shares are freely tradable; institutional investors hold 99.4%.
Largest Shareholders
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| Keeley Teton Small Cap Opportunities | 0.01 | 20,738 | +0.0 | 03/31/2024 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| Lagomarsino Simone | Director | 2,670 | 79,833 $ | Sep 2, 2026 | direct |
| Gardner Steven R | Director | 2,577 | 77,052 $ | Sep 4, 2026 | direct |
| Giem Judi | EVP CHRO | 1,750 | 52,325 $ | Aug 14, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Sep 4, 2026 | Gardner Steven R | Director | Other | 2,577 | 0.00 | – |
| Sep 2, 2026 | Lagomarsino Simone | Director | Other | 2,670 | 0.00 | – |
| Aug 14, 2026 | Giem Judi | EVP CHRO | Other | 643 | 32.69 | 21,020 |
| Aug 14, 2026 | Giem Judi | EVP CHRO | Other | 2,393 | 32.69 | 78,227 |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: September 17, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.