ASP Isotopes Inc. (ASPI) Ownership
ASPI ownership summary
as of October 17, 2026- Institutions
- 48.1% of shares outstanding
- Insiders
- 10.50% of shares outstanding
- Shares outstanding
- 153.3M
- Float
- 133.0M shares available to trade
- Short interest
- 18.85% 26.5M shares short
- Days to cover
- 5.90 short interest up 1.5% vs prior month
- Institutions 48.10%
- Insiders 10.50%
- Other investors 41.40%
ASPI top institutional holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | BlackRock Inc | 6.01% | 9.2M | $19.7M | +889,054 (+10.7%) | June 30, 2026 |
| 2 | Encompass Capital Advisors LLC | 4.28% | 6.6M | $14.0M | −350,300 (−5.1%) | June 30, 2026 |
| 3 | Vanguard Capital Management, LLC | 3.25% | 5.0M | $10.7M | −77,511 (−1.5%) | June 30, 2026 |
| 4 | Rovida Investment Management Ltd | 2.67% | 4.1M | $8.8M | — | June 30, 2026 |
| 5 | UBS Group AG | 2.12% | 3.2M | $6.9M | +405,924 (+14.3%) | June 30, 2026 |
| 6 | Geode Capital Management, LLC | 1.92% | 2.9M | $6.3M | +205,437 (+7.5%) | June 30, 2026 |
| 7 | Alyeska Investment Group, L.P. | 1.85% | 2.8M | $6.1M | +151,337 (+5.6%) | June 30, 2026 |
| 8 | State Street Corp | 1.69% | 2.6M | $5.6M | +273,414 (+11.8%) | June 30, 2026 |
| 9 | Exchange Traded Concepts, LLC | 1.47% | 2.3M | $4.8M | +71,955 (+3.3%) | June 30, 2026 |
| 10 | Awm Investment Company Inc | 1.03% | 1.6M | $3.4M | −543,006 (−25.6%) | June 30, 2026 |
| 11 | BNP Paribas Investment Partners SA | 1.03% | 1.6M | $3.4M | +689,771 (+77.7%) | June 30, 2026 |
| 12 | Philadelphia Financial Mgmt Of San Franc | 0.88% | 1.3M | $2.9M | +694,666 (+107.1%) | June 30, 2026 |
| 13 | Morgan Stanley - Brokerage Accounts | 0.76% | 1.2M | $2.5M | −414,093 (−26.3%) | June 30, 2026 |
| 14 | Vanguard Portfolio Management, LLC | 0.73% | 1.1M | $2.4M | +138,221 (+14.1%) | June 30, 2026 |
| 15 | Northern Trust Corp | 0.66% | 1.0M | $2.2M | +69,691 (+7.4%) | June 30, 2026 |
| 16 | Charles Schwab Investment Management Inc | 0.61% | 935K | $2.0M | +38,116 (+4.2%) | June 30, 2026 |
| 17 | Barclays PLC | 0.55% | 848K | $1.8M | −165,175 (−16.3%) | June 30, 2026 |
| 18 | Marshall Wace Asset Management Ltd | 0.55% | 836K | $1.8M | +835,656 (0.0%) | June 30, 2026 |
| 19 | Man Group PLC | 0.54% | 828K | $1.8M | +828,377 (0.0%) | June 30, 2026 |
| 20 | Vanguard Fiduciary Trust Co | 0.51% | 789K | $1.7M | +35,245 (+4.7%) | June 30, 2026 |
Value at the latest close. Change = shares bought or sold in the latest quarterly filing (13F). In the top 20, 14 holders added 5.3M shares and 5 cut 1.6M.
ASPI top mutual fund and ETF holders
20 largest| # | Holder | % of shares | Shares | Value | Change | Reported |
|---|---|---|---|---|---|---|
| 1 | iShares Russell 2000 ETF | 2.37% | 3.6M | $7.8M | −41,792 (−1.1%) | September 30, 2026 |
| 2 | Vanguard MStar Total Stk Mkt Idx Invest | 2.34% | 3.6M | $7.7M | — | August 31, 2026 |
| 3 | Fidelity Small Cap Index | 0.83% | 1.3M | $2.7M | +11,318 (+0.9%) | July 31, 2026 |
| 4 | American Beacon GLG Natrl Res ETF | 0.80% | 1.2M | $2.6M | — | September 30, 2026 |
| 5 | iShares Russell 2000 Growth ETF | 0.73% | 1.1M | $2.4M | −1,415 (−0.1%) | September 30, 2026 |
| 6 | BNP Clean Energy Solutions C D | 0.63% | 966K | $2.1M | −58 (−0.0%) | August 31, 2026 |
| 7 | Range Nuclear Renaissance ETF | 0.52% | 801K | $1.7M | — | September 30, 2026 |
| 8 | Schwab US Small-Cap ETF™ | 0.47% | 718K | $1.5M | +477 (+0.1%) | September 30, 2026 |
| 9 | Jupiter Merian Glb Eq Abs Rt I USD Acc | 0.45% | 696K | $1.5M | +695,860 (0.0%) | June 30, 2026 |
| 10 | Vanguard Russell 2000 ETF | 0.44% | 669K | $1.4M | +15,662 (+2.4%) | August 31, 2026 |
| 11 | Pacer Data & Infrastructure Rl EsttETF | 0.42% | 641K | $1.4M | −39,117 (−5.8%) | September 30, 2026 |
| 12 | Fidelity Extended Market Index | 0.37% | 566K | $1.2M | +5,063 (+0.9%) | August 31, 2026 |
| 13 | iShares Micro-Cap ETF | 0.29% | 447K | $956,696 | −3,083 (−0.7%) | September 30, 2026 |
| 14 | Anchor FR SA Equity B | 0.28% | 428K | $916,175 | +428,119 (0.0%) | July 31, 2026 |
| 15 | Helfin Global Flexible A (USD) Acc | 0.26% | 405K | $867,443 | +22,375 (+5.8%) | September 30, 2026 |
| 16 | Vanguard Materials ETF | 0.25% | 383K | $819,320 | +66,986 (+21.2%) | August 31, 2026 |
| 17 | Schwab Small Cap Index | 0.19% | 286K | $612,070 | +8,815 (+3.2%) | August 31, 2026 |
| 18 | Nuveen Equity Index R6 | 0.18% | 276K | $589,904 | — | August 31, 2026 |
| 19 | DNB Fund Disrpt Opps A EUR Acc | 0.16% | 252K | $539,194 | +37,080 (+17.3%) | August 31, 2026 |
| 20 | BMO Equal Weight Glbl BM Hdgd to CAD ETF | 0.16% | 248K | $530,067 | — | September 9, 2026 |
Funds report holdings monthly or quarterly; dates differ by fund.
ASPI insider transactions
latest 19| Date | Name | Transaction | Price | Shares | Value |
|---|---|---|---|---|---|
| 2026-04-16 | Robert Ainscow | Sell | $5.21 | 22,500 | $117,225 |
| 2026-04-16 | Duncan Moore | Sell | $5.21 | 11,642 | $60,655 |
| 2026-04-15 | Heather Kiessling | Sell | $5.48 | 23,124 | $126,720 |
| 2026-03-06 | Robert Ainscow | Sell | $5.44 | 8,438 | $45,903 |
| 2026-03-06 | Robert Ainscow | Sell | $4.51 | 25,000 | $112,750 |
| 2025-12-18 | Heather Kiessling | Sell | $5.80 | 80,000 | $464,000 |
| 2025-12-08 | Robert Ainscow | Sell | $6.20 | 8,438 | $52,316 |
| 2025-12-01 | Paul Elliot Mann | Sell | $5.75 | 162,153 | $932,380 |
| 2025-11-25 | Robert Ainscow | Sell | $5.77 | 25,000 | $144,250 |
| 2025-11-25 | Paul Elliot Mann | Sell | $5.77 | 50,000 | $288,500 |
| 2025-11-17 | Paul Elliot Mann | Sell | $7.51 | 112,500 | $844,875 |
| 2025-11-17 | Robert Ainscow | Sell | $7.51 | 67,500 | $506,925 |
| 2025-10-14 | Robert Ainscow | Sell | $13.60 | 22,500 | $306,000 |
| 2025-09-30 | Michael Gorley | Sell | $9.75 | 64,000 | $624,000 |
| 2025-09-15 | Todd Wider | Sell | $8.76 | 74,108 | $649,186 |
| 2025-09-09 | Paul Elliot Mann | Sell | $8.39 | 81,077 | $680,236 |
| 2025-09-08 | Paul Elliot Mann | Sell | $8.53 | 81,076 | $691,578 |
| 2025-09-08 | Robert Ainscow | Sell | $8.53 | 8,438 | $71,976 |
| 2025-08-29 | Duncan Moore | Sell | $9.28 | 75,000 | $696,000 |
Reported trades by company officers, directors and other filers (including disclosures by members of Congress where EODHD lists them). "—" where the filing gives no share count.
ASPI shares outstanding
Year-end shares outstanding, adjusted for splits.
Who owns ASPI
Institutional investors own 48.1% of ASP Isotopes's shares and insiders 10.50%. The largest holder is BlackRock Inc with 6.01% of the shares (9.2M), as of June 30, 2026. Among the top 20 institutions, 14 added shares and 5 reduced their stake in the latest filings. Short interest is 18.85% of the float, or 5.90 days of average trading volume. The share count rose 256.1% since 2020.
Related: ASPI analyst forecast, ASPI key metrics. See the ASPI stock overview for the latest quote and news.
ASPI ownership FAQ
Who owns the most ASP Isotopes stock?
The largest shareholders of ASP Isotopes are BlackRock Inc (6.01%), Encompass Capital Advisors LLC (4.28%), Vanguard Capital Management, LLC (3.25%), Rovida Investment Management Ltd (2.67%), UBS Group AG (2.12%).
What percentage of ASP Isotopes is owned by institutions?
Institutions hold 48.1% of ASP Isotopes's shares outstanding; insiders hold 10.50%.
Which funds own ASP Isotopes?
The largest fund holders of ASP Isotopes are iShares Russell 2000 ETF (2.37%), Vanguard MStar Total Stk Mkt Idx Invest (2.34%), Fidelity Small Cap Index (0.83%), American Beacon GLG Natrl Res ETF (0.80%), iShares Russell 2000 Growth ETF (0.73%).
What is ASP Isotopes's short interest?
26.5M shares of ASP Isotopes were sold short, 18.85% of the float; at the average daily volume it would take 5.90 days to cover.
Are insiders buying or selling ASP Isotopes?
Of the latest 19 reported insider transactions in ASP Isotopes (since August 29, 2025), 0 were purchases and 19 were sales.
How many shares of ASP Isotopes are outstanding?
ASP Isotopes has 153.3M shares outstanding, of which 133.0M are in the public float.