Summary
Updated Aug 31, 2026
Mark A. Finkelstein is Director of COLUMBIA BANKING SYSTEM, INC. (COLB). 1 SEC Form 4 filing on record, dated 18 May 2026.
Recent Transactions
1Every recent SEC Form 4 transaction Mark A. Finkelstein has reported, most recent first.
Trading Pattern
InsiderAlpha's records for Mark A. Finkelstein go back to 2026: 1 primary Form 4 filing, an average of 1.0 per year. No transaction on record carries a Rule 10b5-1 flag - the filings look discretionary rather than pre-scheduled, which makes their timing more informative as a signal.
Other Insiders Active in the Same Stocks
Insiders who reported open-market trades in the last 12 months at the companies Mark A. Finkelstein files at. Multiple unrelated insiders buying the same stock within a short window, cluster buying, has historically been one of the strongest Form 4 signals.
- Steven R. Gardner - $404K of COLB open-market activity in the last 12 months
- Torran B. Nixon - $128K of COLB open-market activity in the last 12 months
- Devine David Moore - $115K of COLB open-market activity in the last 12 months
- Kumi Yamamoto Baruffi - $25K of COLB open-market activity in the last 12 months
- Aaron James Deer - $22K of COLB open-market activity in the last 12 months
- Brock Lakely - $6K of COLB open-market activity in the last 12 months
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
Frequently Asked Questions
Who is Mark A. Finkelstein?
Mark A. Finkelstein is a corporate insider, tracked as Director of COLUMBIA BANKING SYSTEM, INC. (COLB). InsiderAlpha holds 1 primary Form 4 filing for them, the earliest from 2026, updated as new SEC EDGAR filings are processed.
When did Mark A. Finkelstein last file a Form 4?
The only primary Form 4 on record is dated 18 May 2026.
Where can I see all of Mark A. Finkelstein's SEC filings?
All Form 4 filings, transaction values, and 10b5-1 plan flags are listed on this page and updated in real time as new SEC EDGAR filings are processed.
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