Summary
Updated Aug 31, 2026
Mark C. Fuller files SEC Form 4 reports at Castellum, Inc. (CTM). 1 SEC Form 4 filing on record, dated 3 September 2025. Most recent open-market trade: sold $560K of CTM on 3 September 2025. Lifetime open-market sales: $560K.
Recent Transactions
1Every recent SEC Form 4 transaction Mark C. Fuller has reported, most recent first.
Trading Pattern
InsiderAlpha's records for Mark C. Fuller go back to 2025: 1 primary Form 4 filing, an average of 0.5 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 C. Fuller 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.
- Jay O. Wright - $1.30M of CTM open-market activity in the last 12 months
- Charles Thomas McMillen - $65K of CTM open-market activity in the last 12 months
- Glen R. Ives - $9K of CTM open-market activity in the last 12 months
- Andrew Merriman - $4K of CTM open-market activity in the last 12 months
- David T. Bell - $736 of CTM open-market activity in the last 12 months
- Tammy L. Martin - $736 of CTM 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 C. Fuller?
Mark C. Fuller is a corporate insider of Castellum, Inc. (CTM). InsiderAlpha holds 1 primary Form 4 filing for them, the earliest from 2025, updated as new SEC EDGAR filings are processed.
When did Mark C. Fuller last file a Form 4?
The only primary Form 4 on record is dated 3 September 2025.
Has Mark C. Fuller been buying or selling stock?
Recorded transactions: 0 open-market purchases and 1 open-market sale ($560K) across all tracked filings.
Where can I see all of Mark C. Fuller'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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