Summary
Updated Aug 30, 2026
Mark F. Oneil is Director of CARMAX INC (KMX). 4 SEC Form 4 filings on record going back to 2025, most recently on 29 June 2026. Most recent open-market trade: bought $251K of KMX on 26 June 2026. Lifetime open-market purchases: $1.00M.
Recent Transactions
5Every recent SEC Form 4 transaction Mark F. Oneil has reported, most recent first.
Other Insiders Active in the Same Stocks
Insiders who reported open-market trades in the last 12 months at the companies Mark F. Oneil 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.
- Keith Barr - $498K of KMX open-market activity in the last 12 months
- Peter J. Bensen - $131K of KMX open-market activity in the last 12 months
- Sona Chawla - $107K of KMX open-market activity in the last 12 months
- Mitchell D. Steenrod - $91K of KMX open-market activity in the last 12 months
- Marcella Shinder - $30K of KMX 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 F. Oneil?
Mark F. Oneil is a corporate insider, tracked as Director of CARMAX INC (KMX). InsiderAlpha holds 4 primary Form 4 filings for them, the earliest from 2025, updated as new SEC EDGAR filings are processed.
How many SEC Form 4 filings has Mark F. Oneil submitted recently?
2 primary Form 4 filings in the last 90 days, covering 1 company.
Has Mark F. Oneil been buying or selling stock?
Recorded transactions: 3 open-market purchases ($1.00M) and 0 open-market sales across all tracked filings.
Where can I see all of Mark F. Oneil'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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