Summary
Updated Aug 30, 2026
Mark Griffith files SEC Form 4 reports at CoastalSouth Bancshares, Inc. (COSO). 1 SEC Form 4 filing on record, dated 13 February 2026.
Trading Pattern
InsiderAlpha's records for Mark Griffith 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 Griffith 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.
- Anthony P. Valduga - $118K of COSO open-market activity in the last 12 months
- Ernst W. Bruderer - $110K of COSO open-market activity in the last 12 months
- Michael B. High - $38K of COSO open-market activity in the last 12 months
- Stephen R. Stone - $5K of COSO 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 Griffith?
Mark Griffith is a corporate insider of CoastalSouth Bancshares, Inc. (COSO). InsiderAlpha holds 1 primary Form 4 filing for them, the earliest from 2026, updated as new SEC EDGAR filings are processed.
When did Mark Griffith last file a Form 4?
The only primary Form 4 on record is dated 13 February 2026.
Where can I see all of Mark Griffith'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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