William A. Ackman - SEC Form 4 Insider Trading Activity
Summary
Updated Aug 3, 2026
William A. Ackman is a corporate insider tracked by InsiderAlpha. No SEC Form 4 filings recorded in the last 90 days. Lifetime open-market purchases: $259.87M.
Profile
William A. Ackman is a corporate insider at PERSHING SQUARE HOLDCO, L.P. (PS). SEC records also connect Ackman to Pershing Square USA, Ltd. (PSUS) and Pershing Square SPARC Holdings, Ltd.. Ackman has reported 3 insider filings with the SEC since 2026. The most recent filing was in May 2026.
| Role | CEO & Chairman |
|---|---|
| Notability | 45/100 |
| Links | Wikipedia |
Board memberships
- PERSHING SQUARE HOLDCO, L.P.
- Pershing Square USA, Ltd.
- Pershing Square SPARC Holdings, Ltd./DE
Awards & honors
- Founder of Pershing Square Capital Management
- Notable activist investor
- High-profile investments in various companies
Track Record
InsiderAlpha computes a forward-return-based score for every insider with enough Form 4 purchase history. The metrics below reflect realised performance after each tracked open-market purchase.
| Total purchases tracked | 8 |
|---|
Trading Pattern
InsiderAlpha's records for William A. Ackman go back to 2026: 3 primary Form 4 filings, an average of 3.0 per year. The typical open-market purchase is $32.48M (8 buys totaling $259.87M). The largest single buy on record is $175.00M of PSUS in 2026. 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.
Career & Filing History
Every role William A. Ackman has reported on a Form 4, reconstructed from the filings themselves - reporting insiders must state their relationship to the issuer (officer title, director seat, or 10% ownership) on every filing.
- CEO & Chairman at PERSHING SQUARE HOLDCO, L.P. (PS) - 1 filing, 2026
- Chief Executive Officer at Pershing Square USA, Ltd. (PSUS) - 1 filing, 2026
Recent Transactions
| Date | Ticker | Company | Code | Shares | Price | Value |
|---|---|---|---|---|---|---|
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | D - Derivative transaction | 6.87M | $0.00 | |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | G - Bona-fide gift | 300.0K | $0.00 | |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | A - Grant or award | 10.5K | - | |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | J - Other acquisition / disposition | 4.2K | - | |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | J - Other acquisition / disposition | 168.2K | - | |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | P - Open-market purchase | 58.7K | $24.20 | $1.42M |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | P - Open-market purchase | 659.5K | $23.88 | $15.75M |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | P - Open-market purchase | 81.8K | $22.61 | $1.85M |
| 2026-05-05 | PS | PERSHING SQUARE HOLDCO, L.P. | J - Other acquisition / disposition | 700.0K | - | |
| 2026-05-01 | PSUS | Pershing Square USA, Ltd. | P - Open-market purchase | 35.0K | $50.00 | $1.75M |
| 2026-05-01 | PSUS | Pershing Square USA, Ltd. | P - Open-market purchase | 21.2K | $50.00 | $1.06M |
| 2026-05-01 | PSUS | Pershing Square USA, Ltd. | P - Open-market purchase | 841.0K | $50.00 | $42.05M |
| 2026-05-01 | PSUS | Pershing Square USA, Ltd. | P - Open-market purchase | 500.0K | $42.00 | $21.00M |
| 2026-05-01 | PSUS | Pershing Square USA, Ltd. | P - Open-market purchase | 3.50M | $50.00 | $175.00M |
| 2026-04-24 | - | Pershing Square SPARC Holdings, Ltd./DE | J - Other acquisition / disposition | 0 | - |
Most Active Insiders Right Now
William A. Ackman has no recent co-filers at the same companies, so here are the insiders with the largest open-market activity across the market in the last 90 days.
- MetLife Investment Management, LLC - $1600000.00B of FINS open-market activity in the last 90 days
- Magnetar Financial LLC - $16357.48B of CRWV open-market activity in the last 90 days
- Marianne Okland - $18.46B of STNG open-market activity in the last 90 days
- VisionWave Holdings, Inc. - $14.13B of SVRE open-market activity in the last 90 days
- Vanessa Allen Sutherland - $7.44B of PSX open-market activity in the last 90 days
- AI Alpine (Luxembourg) S.a.r.l. - $2.69B of INIO open-market activity in the last 90 days
More Notable Insiders
Other corporate insiders with significant SEC Form 4 track records on InsiderAlpha:
- Gregg Williams
- Stephen T. Wills
- WINMILL CO. INC
- Caroline Young
- Jeffrey Yu
- George Raymond Zage III
- Payam Zamani
- Mahkam Zanganeh
Frequently Asked Questions
Who is William A. Ackman?
William A. Ackman is a corporate insider at PERSHING SQUARE HOLDCO, L.P. (PS). SEC records also connect Ackman to Pershing Square USA, Ltd. (PSUS) and Pershing Square SPARC Holdings, Ltd.. Ackman has reported 3 insider filings with the SEC since 2026. The most recent filing was in May 2026.…
Has William A. Ackman been buying or selling stock?
Recorded transactions: 8 open-market purchases ($259.87M) and 0 open-market sales across all tracked filings.
How accurate is William A. Ackman's historical track record?
Across 8 tracked purchases, William A. Ackman averaged no 30-day data yet with a win rate pending. InsiderAlpha rates the track record at –/5 stars.
Where can I see all of William A. Ackman'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.
Learn More
Open the live William A. Ackman profile on InsiderAlpha for real-time alerts, AI-scored trade ideas, and full transaction history.