LYTIR

Company · COLB

Columbia Banking System, Inc.

Name as listed on its exchange; filed with the SEC as COLUMBIA BANKING SYSTEM, INC.

Nasdaq's symbol directory lists COLB on Nasdaq as “Columbia Banking System, Inc. - Common Stock”.

In the 12 months to Nov 8, 2026: insiders bought on 1 occasion ($22K); insiders sold on 1 occasion ($329K); 1 planned-sale notice; 1 filing by holders of 5% or more; 2 congressional trade disclosures; 3 company reports (Form 8-K, since May 26, 2026).

All insider filings at the SEC

Insider purchases and sales, by month (last 12 months)Insider purchases: $22K in total; Insider sales: $329K in total.Jun: Insider purchases $22KOct: Insider sales $329KDecJanFebMarAprMayJunJulAugSepOctNov
Insider purchases above the line: $22KInsider sales below: $329K
Dollar value of open-market purchases and sales reported on SEC Form 4, by the month traded. Sales include pre-arranged 10b5-1 plan sales.

Insider trades · SEC Form 4

Those inside the hall

Open-market purchases and sales only. Legs one person filed for one day are combined.

Who traded

  1. GARDNER STEVEN R sold on 1 day latest Oct 29, 2026 sold $329K
  2. Deer Aaron James, EVP Chief Strategy/Innov Offcr bought on 1 day latest Jun 30, 2026 bought $22K
Every trade (2)
  1. SELLGARDNER STEVEN R sold Oct 29, 2026 10,522 shares 7 legs combined filing $329K
  2. BUYDeer Aaron James, EVP Chief Strategy/Innov Offcr bought Jun 30, 2026 886 shares filing $22K

Planned sales · SEC Form 144

Notice given

A Form 144 is filed before an insider sells restricted stock. It states an intent; the sale, if it happens, appears later on a Form 4. Every recent notice

  1. GARDNER STEVEN R filed Oct 29, 2026 Director 10,522 shares planned sale date 10/29/2026 filing $329K

Large holders · SEC Schedules 13D and 13G

Five percent and over

Anyone who comes to hold more than 5% of a company's voting shares must tell the SEC. A Schedule 13D is filed by a holder who may seek to influence the company; a 13G by one who states it is a passive investor. An amendment updates an earlier filing, and a stake reported as 0% means the holder says it has sold all, or nearly all, of its shares. Every recent 13D and 13G

  1. Wellington Management Group LLP filed Aug 13, 2026 Schedule 13G/A passive filing 4.13%

Congress · STOCK Act

The Althing

Periodic transaction reports. Amounts are the ranges members report; the trade date is when it happened, the report can come up to 45 days later.

  1. Josh Gottheimer (D-NJ05): Sale Mar 5, 2026 reported Apr 8, 2026 one of 18 trades the member reported that day House Stocks (including ADRs) owner: joint $1,001 - $15,000
  2. Gilbert Cisneros (D-CA31): Sale Jan 15, 2026 reported Feb 13, 2026 one of 151 trades the member reported that day House Stocks (including ADRs) $15,001 - $50,000

Company reports · SEC Form 8-K

In its own words

Current reports the company filed with the SEC; most items are due within four business days of the event. Each line lists the report's items by the SEC's own titles; the filing says what happened. Reports collected since May 26, 2026; every 8-K at the SEC.

  1. Departure or appointment of directors or officers filing Oct 27, 2026
  2. Results of operations and financial condition; Regulation FD disclosure filing Oct 22, 2026
  3. Regulation FD disclosure filing Sep 30, 2026

Sources: SEC EDGAR (Forms 4, 144 and 8-K) and STOCK Act periodic transaction reports. Filings can be late, amended or wrong at the source; see methodology.