Mark Herndon
Chief Financial Officer · Horizon Kinetics Holding Corp
- 2025
- Aug 20, 2026
- 4
Other insiders active in the same stocks
Insiders who reported open-market trades in the last 12 months at the companies Mark Herndon 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.
- Brent D. Rosenthal - $106K in HKHC purchases and sales in the last 12 months
- Alice C. Brennan - $26K in HKHC purchases and sales in the last 12 months
- Daniel J. Roller - $13K in HKHC purchases and sales in the last 12 months
- Murray Stahl - $12K in HKHC purchases and sales in the last 12 months
- Allison Nagelberg - $10K in HKHC purchases and sales in the last 12 months
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Frequently asked questions
Who is Mark Herndon?
Mark Herndon is a corporate insider, tracked as Chief Financial Officer of Horizon Kinetics Holding Corp (HKHC). 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 Herndon submitted recently?
1 primary Form 4 filing in the last 90 days, covering 1 company.
Has Mark Herndon been buying or selling stock?
Recorded transactions: 5 open-market purchases ($15K) and 0 open-market sales across all tracked filings.
