Columbia Banking System, Inc. (COLB) Insider Trading
Over the last 3 months, COLB insiders made 1 open-market buy and 2 sales, a net sale of -$93K (SEC Form 4). Over the last 6 months, 372 institutions increased and 385 reduced their position (13F).
Insider Activity
Sentiment
16/100
Buys (3m)
1
Sells (3m)
2
Net (3m)
-$92.8K
Insiders buying
Insider trades by month Buys Sells
Mar
Feb
Mar
Jun
Jul
Context3-month price +1.5%Institutions accumulating (13F)
| Date | Insider | Type | Shares | Price |
|---|---|---|---|---|
| Aug 18, 2026 | Giem Judiofficer: EVP CHRO | Tax | 643 | $32.69 |
| Aug 18, 2026 | Giem Judiofficer: EVP CHRO | Option | 2,393 | $32.69 |
| Jul 2, 2026 | Deer Aaron Jamesofficer: EVP Chief Strategy/Innov Offcr | Buy | 886 | $25.37 |
| Jun 16, 2026 | MACHUCA LUISdirector | Grant | 563 | — |
| Jun 10, 2026 | Moore Devine Davidofficer: EVP Chief Marketing Officer | Sell | 60 | $29.77 |
| Jun 10, 2026 | Moore Devine Davidofficer: EVP Chief Marketing Officer | Sell | 3,812 | $29.77 |
| May 18, 2026 | Lund Randal Leedirector | Grant | 3,949 | — |
| May 18, 2026 | Forrest Ericdirector | Grant | 3,949 | — |
| May 18, 2026 | Finkelstein Mark Adirector | Grant | 3,949 | — |
| May 18, 2026 | STUDENMUND JAYNIE Mdirector | Grant | 3,949 | — |
| May 18, 2026 | Terry Hilliard C. IIIdirector | Grant | 3,949 | — |
| May 18, 2026 | MACHUCA LUISdirector | Grant | 3,949 | — |
| May 18, 2026 | Varnado Anddriadirector | Grant | 3,949 | — |
| May 18, 2026 | MITCHELL M CHRISTIANdirector | Grant | 3,949 | — |
| May 18, 2026 | SEATON ELIZABETH WHITEHEADdirector | Grant | 3,949 | — |
| May 18, 2026 | SCHULTZ JOHN Fdirector | Grant | 3,949 | — |
| Apr 16, 2026 | Lakely Brockofficer: EVP, Chief Accounting Officer | Tax | 396 | $29.10 |
| Mar 20, 2026 | Lakely Brockofficer: EVP, Chief Accounting Officer | Tax | 211 | $26.23 |
| Mar 20, 2026 | BARUFFI KUMI YAMAMOTOofficer: EVP General Counsel, Corp Sec | Tax | 937 | $26.23 |
| Mar 17, 2026 | MACHUCA LUISdirector | Grant | 659 | — |
| Mar 17, 2026 | Nixon Torran Bofficer: Senior Executive VP | Tax | 2,002 | $26.23 |
| Mar 17, 2026 | Stein Clintdirector, officer: Chair, CEO, President | Tax | 7,151 | $26.23 |
| Mar 17, 2026 | Stein Clintdirector, officer: Chair, CEO, President | Option | 18,171 | $26.23 |
| Mar 17, 2026 | Namdar Frankofficer: EVP Chief Credit Officer | Option | 2,820 | $26.23 |
| Mar 17, 2026 | Lakely Brockofficer: EVP, Chief Accounting Officer | Sell | 211 | $26.23 |
| Mar 17, 2026 | Merrywell Christopherofficer: Senior Executive VP | Option | 5,013 | $26.23 |
| Mar 17, 2026 | Anderson Drew Kofficer: EVP Chief Admin Officer | Option | 2,506 | $26.23 |
| Mar 17, 2026 | Nixon Torran Bofficer: Senior Executive VP | Option | 5,013 | $26.23 |
| Mar 17, 2026 | Deer Aaron Jamesofficer: EVP Chief Strategy/Innov Offcr | Tax | 617 | $26.23 |
| Mar 17, 2026 | Anderson Drew Kofficer: EVP Chief Admin Officer | Tax | 1,215 | $26.23 |
Source: COLB SEC Form 4 filings, latest Aug 18, 2026. For informational purposes only — not investment advice.
Institutional activity (13F)
How institutions changed their COLB positions over the last 6 months (SEC Form 13F).
Increased
372
New positions
159
Reduced
385
Sold out
49
Largest moves
| Institution | Action | Shares | Filed |
|---|---|---|---|
| BlackRock, Inc. | Increased | 27.5M | Aug 7, 2026 |
| BLACKROCK, INC. | Increased | 27.1M | May 13, 2026 |
| T. ROWE PRICE INVESTMENT MANAGEMENT, INC. | Reduced | 15.9M | May 15, 2026 |
| T. Rowe Price Investment Management, Inc. | Reduced | 15.6M | Aug 14, 2026 |
| WELLINGTON MANAGEMENT GROUP LLP | Reduced | 14.9M | May 15, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | New Position | 14.3M | May 8, 2026 |
| DIMENSIONAL FUND ADVISORS LP | Increased | 13.9M | Aug 11, 2026 |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Reduced | 13.7M | Aug 13, 2026 |
| DIMENSIONAL FUND ADVISORS LP | Increased | 13.5M | May 7, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | New Position | 13.2M | May 15, 2026 |
| VANGUARD CAPITAL MANAGEMENT LLC | Reduced | 13.1M | Aug 13, 2026 |
| STATE STREET CORP | Increased | 12.7M | Aug 7, 2026 |
| STATE STREET CORP | Reduced | 12.5M | May 15, 2026 |
| WELLINGTON MANAGEMENT GROUP LLP | Reduced | 11.7M | Aug 14, 2026 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | Increased | 11.0M | Aug 14, 2026 |
Source: SEC Form 13F filings. For informational purposes only — not investment advice.