Summary
Updated Aug 30, 2026
Matthew J. Mainer is EVP, CFO & TREASURER of Post Holdings, Inc. (POST). 12 SEC Form 4 filings on record going back to 2024, most recently on 5 December 2025.
Recent Transactions
20Every recent SEC Form 4 transaction Matthew J. Mainer has reported, most recent first.
Trading Pattern
InsiderAlpha's records for Matthew J. Mainer go back to 2024: 12 primary Form 4 filings, an average of 4.0 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 Matthew J. Mainer 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.
- Gregory L. Curl - $1.45M of POST open-market activity in the last 12 months
- Nicolas Catoggio - $1.00M of POST open-market activity in the last 12 months
- David W. Kemper - $176K of POST 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 Matthew J. Mainer?
Matthew J. Mainer is a corporate insider, tracked as EVP, CFO & TREASURER of Post Holdings, Inc. (POST). InsiderAlpha holds 12 primary Form 4 filings for them, the earliest from 2024, updated as new SEC EDGAR filings are processed.
When did Matthew J. Mainer last file a Form 4?
The most recent primary Form 4 on record is dated 5 December 2025, one of 12 filings going back to 2024.
Where can I see all of Matthew J. Mainer'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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