Summary
Updated Aug 31, 2026
Henry A. Clark III files SEC Form 4 reports at SOUTHERN CO (SO). 1 SEC Form 4 filing on record, dated 2 October 2024.
Trading Pattern
InsiderAlpha's records for Henry A. Clark III go back to 2024: 1 primary Form 4 filing, an average of 0.3 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 Henry A. Clark III 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.
- Kimberly S, Greene - $2.42M of SO open-market activity in the last 12 months
- Stan W. Connally - $1.21M of SO open-market activity in the last 12 months
- Christopher Cummiskey - $644K of SO open-market activity in the last 12 months
- Bryan D. Anderson - $582K of SO open-market activity in the last 12 months
- Matthew M. Kim - $525K of SO open-market activity in the last 12 months
- Sterling A. Spainhour Jr. - $313K of SO 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 Henry A. Clark III?
Henry A. Clark III is a corporate insider of SOUTHERN CO (SO). InsiderAlpha holds 1 primary Form 4 filing for them, the earliest from 2024, updated as new SEC EDGAR filings are processed.
When did Henry A. Clark III last file a Form 4?
The only primary Form 4 on record is dated 2 October 2024.
Where can I see all of Henry A. Clark III'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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