ASP Isotopes Inc.
Ownership
Ownership Structure
Who owns ASP Isotopes Inc. (ASPI)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 86.8% of the shares are freely tradable; institutional investors hold 57.1%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| BlackRock Inc | 5.43 | 8,328,144 | +22.7 | 03/31/2026 |
| Encompass Capital Advisors LLC | 4.51 | 6,912,054 | +0.0 | 03/31/2026 |
| Vanguard Capital Management, LLC | 3.30 | 5,060,464 | +0.0 | 03/31/2026 |
| Rovida Investment Management Ltd | 2.67 | 4,100,000 | +0.0 | 06/30/2026 |
| UBS Group AG | 1.85 | 2,841,709 | +18.1 | 03/31/2026 |
| Geode Capital Management, LLC | 1.79 | 2,740,464 | +14.9 | 03/31/2026 |
| Alyeska Investment Group, L.P. | 1.76 | 2,692,166 | -45.0 | 03/31/2026 |
| State Street Corp | 1.51 | 2,322,159 | +25.9 | 03/31/2026 |
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| Vanguard MStar Total Stk Mkt Idx Invest | 2.34 | 3,593,895 | +0.0 | 07/31/2026 |
| iShares Russell 2000 ETF | 1.95 | 2,996,232 | -0.6 | 08/31/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| Mann Paul Elliot | Chairman and CEO | 9,328,570 | 29,851,424 $ | Sep 4, 2026 | direct |
| Ainscow Robert | COO | 2,248,441 | 7,195,011 $ | Sep 8, 2026 | direct |
| Ainscow Donald George | EVP, Gen Counsel, Secretary | 776,322 | 2,484,230 $ | Sep 2, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Sep 8, 2026 | Ainscow Robert | COO | Sell | 8,438 | 4.29 | 36,216 |
| Sep 4, 2026 | Mann Paul Elliot | Chairman and CEO | Sell | 83,759 | 4.10 | 343,412 |
| Sep 3, 2026 | Mann Paul Elliot | Chairman and CEO | Sell | 83,758 | 3.92 | 328,331 |
| Sep 2, 2026 | Ainscow Donald George | EVP, Gen Counsel, Secretary | Sell | 23,678 | 3.89 | 92,107 |
| Sep 2, 2026 | Ainscow Robert | COO | Sell | 25,000 | 3.91 | 97,625 |
| Sep 2, 2026 | Mann Paul Elliot | Chairman and CEO | Sell | 83,758 | 3.91 | 327,494 |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: September 17, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.