Summary
Updated Aug 31, 2026
Mark W. Sheahan files SEC Form 4 reports at TENNANT CO (TNC). 4 SEC Form 4 filings on record going back to 2025, most recently on 11 May 2026.
Recent Transactions
4Every recent SEC Form 4 transaction Mark W. Sheahan has reported, most recent first.
Trading Pattern
InsiderAlpha's records for Mark W. Sheahan go back to 2025: 4 primary Form 4 filings, an average of 2.0 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 W. Sheahan 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.
- Claudio Merengo - $1.25M of GGG open-market activity in the last 12 months
- J. Kevin Gilligan - $1.15M of GGG open-market activity in the last 12 months
- Donal L. Mulligan - $1.04M of TNC open-market activity in the last 12 months
- Peter J. O'Shea - $777K of GGG open-market activity in the last 12 months
- Richard H. Zay - $605K of TNC open-market activity in the last 12 months
- James T. Glerum Jr. - $500K of TNC 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 W. Sheahan?
Mark W. Sheahan is a corporate insider of TENNANT CO (TNC). InsiderAlpha holds 4 primary Form 4 filings for them, the earliest from 2025, updated as new SEC EDGAR filings are processed.
When did Mark W. Sheahan last file a Form 4?
The most recent primary Form 4 on record is dated 11 May 2026, one of 4 filings going back to 2025.
Where can I see all of Mark W. Sheahan'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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