Nasdaq · CIK 0001921865
ASPI ASP Isotopes Inc.
Insider trading from SEC Form 4. Last filing 12 d ago. Close $2.65 on Oct 9, 2026, +2% from the 52-week low and -81% from the high.
ASP Isotopes Inc. (ASPI) has 47 SEC Form 4 filings on file from 9 insiders, the latest filed on Oct 1, 2026. In the last 90 days insiders made 2 open-market buys worth $62k and 4 open-market sells worth $1.2M, net -$1.2M.
28 open-market trades have been scored at ASPI. The newest: Robert John Andrew Ryan (director) bought $40k of stock on Sep 30, 2026, filed Oct 1, 2026, scored 44 (moderate). The largest of the 28 shown: Paul Elliot Mann (Chief Executive Officer) sold $5.3M on Apr 15, 2025, scored 43 (moderate), under a 10b5-1 plan. 3 insiders sold within 14 days of each other around Sep 8, 2026.
ASPI closed at $2.65 on Oct 9, 2026, 2% above its 52-week low and 81% below its 52-week high.
12 Form 144 notices of planned sales are on file, the latest filed Dec 18, 2025.
Last 90 days
Price and insider trades, last year
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value. Click a marked bar to open the signal.Charts by TradingView Lightweight Charts™
Signals
Open-market buys and sells at ASP Isotopes Inc., scored.
| Score | Insider | Value | Holdings | Price context | Filed |
|---|---|---|---|---|---|
| 44Moderate | Robert John Andrew Ryan director buy | $40k 15,000 shares | +2% | +2% from low-81% from high | |
| 33Weak | Robert John Andrew Ryan director buy | $22k 8,000 shares | +1% | 0% from low-81% from high | |
| 21Weak | Robert Ainscow COO sell | $36k 8,438 shares | -0% | - | |
| 45Moderate | Paul Elliot Mann Chairman and CEO sell | $999k 251,275 shares | -3% | - | |
| 25Weak | Robert Ainscow COO sell | $98k 25,000 shares | -1% | - | |
| 39Weak | Donald George Ainscow EVP, Gen Counsel, Secretary sell | $92k 23,678 shares | -3% | - | |
| 15Weak | Robert Ainscow COO sell | $59k 8,438 shares | -0% | +68% from low-51% from high | |
| 38Weak | Paul Elliot Mann Chairman and CEO sell | $2.0M 251,275 shares | -3% | +97% from low-43% from high | |
| 17Weak | Duncan Moore director sell | $61k 11,642 shares | -1% | +26% from low-64% from high | |
| 28Weak | Heather Kiessling Chief Financial Officer sell | $127k 23,124 shares | -3% | +32% from low-62% from high | |
| 25Weak | Robert Ainscow COO sell | $117k 22,500 shares | -1% | +26% from low-64% from high | |
| 18Weak | Robert Ainscow COO sell | $113k 25,000 shares | -2% | +42% from low-61% from high | |
| 14Weak | Robert Ainscow COO sell | $46k 8,438 shares | -1% | +42% from low-61% from high | |
| 31Weak | Paul Elliot Mann Executive Chairman sell | $881k 162,153 shares | -2% | +40% from low-61% from high | |
| 47Moderate | Heather Kiessling Chief Financial Officer sell | $464k 80,000 shares | -10% | +48% from low-59% from high | |
| 27Weak | Robert Ainscow Interim CEO and COO sell | $52k 8,438 shares | -1% | +56% from low-56% from high | |
| 32Weak | Paul Elliot Mann Executive Chairman sell | $933k 162,153 shares | -2% | +42% from low-60% from high | |
| 28Weak | Paul Elliot Mann Executive Officer sell | $1.1M 162,500 shares | -2% | +85% from low-48% from high | |
| 24Weak | Robert Ainscow Interim CEO and COO sell | $144k 25,000 shares | -2% | +53% from low-57% from high | |
| 31Weak | Robert Ainscow Interim CEO and COO sell | $507k 67,500 shares | -4% | +85% from low-48% from high | |
| 27Weak | Robert Ainscow Interim CEO and COO sell | $306k 22,500 shares | -1% | +384% from low0% from high | |
| 35Weak | Todd Wider director sell | $649k 74,108 shares | -9% | +249% from low-17% from high | |
| 53Moderate | Michael Gorley director sell | $624k 64,000 shares | -44% | +263% from low-16% from high | |
| 30Weak | Paul Elliot Mann Chief Executive Officer sell | $1.4M 162,153 shares | -2% | +238% from low-24% from high | |
| 8Weak | Robert Ainscow Chief Operating Officer sell | $72k 8,438 shares | -1% | +238% from low-24% from high | |
| 51Moderate | Duncan Moore director sell | $696k 75,000 shares | -7% | +268% from low-17% from high | |
| 43Moderate | Paul Elliot Mann Chief Executive Officer sell | $5.3M 950,000 shares | -11% | +127% from low-35% from high | |
| 38Weak | Robert Ainscow Chief Operating Officer sell | $1.1M 200,000 shares | -12% | +127% from low-35% from high |
Planned sales
Form 144 notices filed before a sale of restricted or control stock, newest first. The sale itself usually reaches a Form 4 within days. All planned sales
| Filed | Seller | Shares | Value | Sale date | Past 3 months |
|---|---|---|---|---|---|
| Dec 18, 2025 | Heather Kiessling Chief Financial Officer | 80,000 0.07% of outstanding | $461k | Dec 18, 2025 | none |
| Dec 11, 2025 | Ainscow Robert OFFICER | 8,438 0.01% of outstanding | $52k | Dec 8, 2025 | $1.0M |
| Nov 25, 2025 | Mann Paul Elliot DIRECTOR, OFFICER | 112,500 0.10% of outstanding | $731k | Nov 15, 2025 | $1.4M |
| Nov 17, 2025 | Ainscow Robert OFFICER | 67,500 0.06% of outstanding | $439k | Nov 17, 2025 | $378k |
| Oct 16, 2025 | Ainscow Robert OFFICER | 22,500 0.02% of outstanding | $300k | Oct 14, 2025 | $72k |
| Sep 30, 2025 | Gorley Michael DIRECTOR | 64,000 0.07% of outstanding | $662k | Sep 30, 2025 | none |
| Sep 12, 2025 | Todd Wider Director | 75,000 0.08% of outstanding | $658k | Sep 12, 2025 | none |
| Sep 8, 2025 | Mann Paul Elliot Officer, Director, 10% Stockholder | 8,438 0.01% of outstanding | $69k | Sep 8, 2025 | none |
| Sep 8, 2025 | Ainscow Robert Officer | 8,438 0.01% of outstanding | $69k | Sep 8, 2025 | none |
| Aug 29, 2025 | Moore Duncan Director | 75,000 0.08% of outstanding | $790k | Aug 29, 2025 | none |
| Apr 15, 2025 | Mann Paul Elliot Officer, Director, 10% Stockholder | 950,000 1.32% of outstanding | $6.0M | Apr 15, 2025 | none |
| Apr 15, 2025 | Ainscow Robert Officer | 200,000 0.28% of outstanding | $1.3M | Apr 15, 2025 | none |
Transactions
The newest 50 of 79 rows filed, every code.
| Date | Insider | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| Sep 30, 2026 | Robert John Andrew Ryan director | POpen-market purchase Common Stock | +15,000 | $2.68 | $40k | 675,222 | 12 d ago |
| Sep 28, 2026 | Robert John Andrew Ryan director | POpen-market purchase Common Stock | +8,000 | $2.70 | $22k | 660,222 | 13 d ago |
| Sep 8, 2026 | Robert Ainscow COO | SOpen-market sale Common Stock10b5-1 | -8,438 | $4.29 | $36k | 2,248,441 | 33 d ago |
| Sep 2, 2026 | Donald George Ainscow EVP, Gen Counsel, Secretary | SOpen-market sale Common Stock | -23,678 | $3.89 | $92k | 776,322 | 39 d ago |
| Sep 2, 2026 | Robert Ainscow COO | SOpen-market sale Common Stock10b5-1 | -25,000 | $3.91 | $98k | 2,256,879 | 39 d ago |
| Sep 2, 2026 | Paul Elliot Mann Chairman and CEO | SOpen-market sale Common Stock10b5-1 | -83,758 | $3.91 | $327k | 9,496,087 | 39 d ago |
| Sep 3, 2026 | Paul Elliot Mann Chairman and CEO | SOpen-market sale Common Stock10b5-1 | -83,758 | $3.92 | $328k | 9,412,329 | 39 d ago |
| Sep 4, 2026 | Paul Elliot Mann Chairman and CEO | SOpen-market sale Common Stock10b5-1 | -83,759 | $4.10 | $343k | 9,328,570 | 39 d ago |
| Jun 8, 2026 | Robert Ainscow COO | SOpen-market sale Common Stock10b5-1 | -8,438 | $7.00 | $59k | 2,281,879 | Jun 10, 2026 |
| May 28, 2026 | Paul Elliot Mann Chairman and CEO | AGrant or award Common Stock10b5-1 | +2,233,555 | - | - | 9,830,940 | Jun 3, 2026 |
| May 28, 2026 | Donald George Ainscow EVP, Gen Counsel, Secretary | AGrant or award Common Stock | +400,000 | - | - | 900,000 | Jun 3, 2026 |
| May 28, 2026 | Heather Kiessling Chief Financial Officer | AGrant or award Common Stock | +840,000 | - | - | 1,549,376 | Jun 3, 2026 |
| May 28, 2026 | Robert Ainscow Chief Operating Officer | AGrant or award Common Stock | +800,000 | - | - | 2,290,317 | Jun 3, 2026 |
| Jun 1, 2026 | Paul Elliot Mann Chairman and CEO | SOpen-market sale Common Stock10b5-1 | -83,758 | $7.88 | $660k | 9,747,182 | Jun 3, 2026 |
| Jun 2, 2026 | Paul Elliot Mann Chairman and CEO | SOpen-market sale Common Stock10b5-1 | -83,758 | $8.29 | $694k | 9,663,424 | Jun 3, 2026 |
| Jun 3, 2026 | Paul Elliot Mann Chairman and CEO | SOpen-market sale Common Stock10b5-1 | -83,759 | $7.76 | $650k | 9,579,845 | Jun 3, 2026 |
| Apr 16, 2026 | Robert Ainscow COO | SOpen-market sale Common Stock10b5-1 | -22,500 | $5.21 | $117k | 1,490,317 | Apr 17, 2026 |
| Apr 15, 2026 | Heather Kiessling Chief Financial Officer | SOpen-market sale Common Stock10b5-1 | -23,124 | $5.48 | $127k | 709,376 | Apr 17, 2026 |
| Nov 12, 2025 | Duncan Moore director | AGrant or award Common Stock10b5-1 | +25,469 | - | - | 1,020,022 | Apr 17, 2026 |
| Dec 18, 2025 | Duncan Moore director | AGrant or award Common Stock10b5-1 | +36,548 | - | - | 1,056,570 | Apr 17, 2026 |
| Apr 16, 2026 | Duncan Moore director | SOpen-market sale Common Stock10b5-1 | -11,642 | $5.21 | $61k | 1,044,928 | Apr 17, 2026 |
| Mar 6, 2026 | Robert Ainscow COO | SOpen-market sale Common Stock10b5-1 | -25,000 | $4.51 | $113k | 1,512,817 | Apr 13, 2026 |
| Mar 6, 2026 | Robert Ainscow COO | SOpen-market sale Common Stock10b5-1 | -8,438 | $5.44 | $46k | 1,537,817 | Mar 6, 2026 |
| Mar 2, 2026 | Paul Elliot Mann Executive Chairman | SOpen-market sale Common Stock10b5-1 | +162,153 | $5.44 | $881k | 7,597,385 | Mar 2, 2026 |
| Dec 18, 2025 | Heather Kiessling Chief Financial Officer | SOpen-market sale Common Stock | -80,000 | $5.80 | $464k | 732,500 | Dec 29, 2025 |
| Dec 18, 2025 | Todd Wider director | AGrant or award Common Stock | +36,548 | - | - | 772,247 | Dec 22, 2025 |
| Dec 18, 2025 | Robert John Andrew Ryan director | AGrant or award Common Stock | +36,548 | - | - | 652,222 | Dec 22, 2025 |
| Dec 18, 2025 | Michael Gorley director | AGrant or award Common Stock | +36,548 | - | - | 117,908 | Dec 22, 2025 |
| Dec 18, 2025 | Ralph L. Hunter JR director | AGrant or award Common Stock | +36,548 | - | - | 47,018 | Dec 22, 2025 |
| Dec 8, 2025 | Robert Ainscow Interim CEO and COO | SOpen-market sale Common Stock10b5-1 | -8,438 | $6.20 | $52k | 1,546,255 | Dec 11, 2025 |
| Dec 1, 2025 | Paul Elliot Mann Executive Chairman | SOpen-market sale Common Stock10b5-1 | -162,153 | $5.75 | $933k | 7,759,538 | Dec 3, 2025 |
| Nov 25, 2025 | Robert Ainscow Interim CEO and COO | SOpen-market sale Common Stock10b5-1 | -25,000 | $5.77 | $144k | 1,554,693 | Nov 28, 2025 |
| Nov 17, 2025 | Paul Elliot Mann Executive Officer | SOpen-market sale Common Stock10b5-1 | -112,500 | $7.51 | $845k | 7,971,691 | Nov 28, 2025 |
| Aug 1, 2025 | Donald George Ainscow EVP, Gen Counsel, Secretary | AGrant or award Common Stock | +400,000 | - | - | 500,000 | Nov 28, 2025 |
| Sep 6, 2025 | Ralph L. Hunter JR director | AGrant or award Common Stock | +10,470 | - | - | 10,470 | Nov 28, 2025 |
| Nov 25, 2025 | Paul Elliot Mann Executive Officer | SOpen-market sale Common Stock10b5-1 | -50,000 | $5.77 | $288k | 7,921,691 | Nov 28, 2025 |
| Nov 17, 2025 | Robert Ainscow Interim CEO and COO | SOpen-market sale Common Stock10b5-1 | -67,500 | $7.51 | $507k | 1,579,693 | Nov 19, 2025 |
| Nov 12, 2025 | Todd Wider director | AGrant or award Common Stock | +25,469 | - | - | 735,699 | Nov 14, 2025 |
| Oct 14, 2025 | Robert Ainscow Interim CEO and COO | SOpen-market sale Common Stock10b5-1 | -22,500 | $13.60 | $306k | 1,647,193 | Oct 16, 2025 |
| Sep 14, 2025 | Todd Wider director | MOption exercise Common Stock | +96,000 | $2.00 | $192k | 806,230 | Oct 3, 2025 |
| Sep 14, 2025 | Todd Wider director | FTax withholding Common Stock | -21,892 | $8.77 | $192k | 784,338 | Oct 3, 2025 |
| Sep 15, 2025 | Todd Wider director | SOpen-market sale Common Stock | -74,108 | $8.76 | $649k | 710,230 | Oct 3, 2025 |
| Sep 14, 2025 | Todd Wider director | MOption exercise Stock Option (right to buy)derivative | -96,000 | $0.00 | $0 | 0 | Oct 3, 2025 |
| Sep 30, 2025 | Michael Gorley director | SOpen-market sale Common Stock | -64,000 | $9.75 | $624k | 81,360 | Oct 2, 2025 |
| Sep 8, 2025 | Robert Ainscow Chief Operating Officer | SOpen-market sale Common Stock10b5-1 | -8,438 | $8.53 | $72k | 1,411,554 | Sep 10, 2025 |
| Sep 8, 2025 | Paul Elliot Mann Chief Executive Officer | SOpen-market sale Common Stock10b5-1 | -81,076 | $8.53 | $691k | 7,234,378 | Sep 10, 2025 |
| Sep 9, 2025 | Paul Elliot Mann Chief Executive Officer | MOption exercise Common Stock10b5-1 | +216,000 | $2.00 | $432k | 7,450,378 | Sep 10, 2025 |
| Sep 9, 2025 | Robert Ainscow Chief Operating Officer | MOption exercise Common Stock10b5-1 | +150,000 | $0.25 | $38k | 1,564,554 | Sep 10, 2025 |
| Sep 9, 2025 | Paul Elliot Mann Chief Executive Officer | FTax withholding Common Stock10b5-1 | -50,644 | $8.53 | $432k | 7,399,734 | Sep 10, 2025 |
| Sep 9, 2025 | Robert Ainscow Chief Operating Officer | FTax withholding Common Stock10b5-1 | -4,396 | $8.53 | $37k | 1,557,158 | Sep 10, 2025 |
Insiders
Everyone who has filed a Form 4 here.
- Donald George AinscowEVP, Gen Counsel, Secretary
- Robert AinscowCOO
- Michael Gorleydirector
- Ralph L. Hunter JRdirector
- Heather KiesslingChief Financial Officer
- Paul Elliot MannChairman and CEO
- Duncan Mooredirector
- Robert John Andrew Ryandirector
- Todd Widerdirector
Questions about ASPI
Answered from the filings on this page, as of the latest one.
Are insiders buying ASPI?
As of Oct 1, 2026, SEC Form 4 filings show 2 open-market buys worth $62k by 1 insider and 4 open-market sells worth $1.2M by 3 insiders at ASP Isotopes Inc. in the last 90 days, net -$1.2M. Only purchases (code P) and sales (code S) count; grants, option exercises and tax withholding do not.
Who was the last insider to trade ASPI on the open market?
Robert John Andrew Ryan (director) bought $40k of ASPI on Sep 30, 2026 and filed the Form 4 on Oct 1, 2026. InsiderTell scored 44 (moderate).
How many insiders file Form 4 at ASP Isotopes Inc.?
9 people have filed a Form 4 at ASP Isotopes Inc., among them Donald George Ainscow (EVP, Gen Counsel, Secretary), Robert Ainscow (COO), Michael Gorley (director). Officers, directors and holders of more than 10% of a share class must report their trades within two business days.
Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.