Every Form 4 that ASP Isotopes Inc. (ASPI) has filed with the SEC in the last 12 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A Form 4 covers the transactions officers, directors and large holders report, so if you follow ASPI and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full ASPI filings page.
ASP Isotopes Inc. director Robert John Andrew Ryan purchased 15,000 shares of common stock at a weighted average price of $2.68 per share. The footnote says the shares were purchased in multiple transactions at prices from $2.65 to $2.68, inclusive. His reported direct holdings after the purchase were 675,222 shares. No Rule 10b5-1 plan is reported.
ASP Isotopes Inc. director Robert John Andrew Ryan purchased 8,000 shares of common stock at a weighted average price of $2.70 per share. Ryan directly held 660,222 shares following the transaction. No Rule 10b5-1 plan is reported.
ASP Isotopes Inc. (ASPI) reported that its COO, Robert Ainscow, sold 8,438 shares of common stock in an open-market transaction at a weighted average price of $4.292 per share, with prices ranging from $4.185 to $4.39. According to the disclosure, this was a "sell to cover" transaction executed under a Rule 10b5-1 trading plan adopted on June 9, 2025 to cover tax withholding obligations from vesting restricted stock awards. Following the sale, Ainscow directly holds 2,248,441 shares of ASP Isotopes common stock.
ASP Isotopes Inc. (ASPI) reported that executive officer Donald George Ainscow, EVP, General Counsel and Secretary, had 23,678 shares of common stock sold to cover tax obligations arising from an equity award. The company executed these shares under a mandatory sell-to-cover provision and stated the sale was not a discretionary trade by Ainscow. After these sales, he holds 776,322 shares of common stock directly.
ASP Isotopes Inc. (ASPI) reported that its chief operating officer, Robert Ainscow, sold 25,000 shares of common stock in an open market or private transaction under a Rule 10b5-1 trading plan. The weighted average sale price was about $3.91 per share, and he now directly holds 2,256,879 shares.
ASP Isotopes Inc. (ASPI) reported that Chairman and CEO Paul Elliot Mann sold a total of 251,275 shares of common stock in three transactions, all described as sell-to-cover sales effected under a Rule 10b5-1 trading plan adopted on December 30, 2025 to cover tax withholding obligations on quarterly vesting of a restricted stock award.
The reported weighted average prices were $3.91 for 83,758 shares (range $3.75–$3.96), $3.92 for 83,758 shares (range $3.875–$3.98), and $4.10 for 83,759 shares (range $3.925–$4.26). Post-transaction share holdings are not stated in this data.
ASP Isotopes Inc.’s Chief Financial Officer, Heather Kiessling, reported an open-market sale of 23,124 shares of common stock at a weighted average price of $6.28 per share. According to the footnotes, these were “sell to cover” trades under a Rule 10b5-1 trading plan to satisfy tax withholding from quarterly vesting of a restricted stock award.
After the transaction, she directly holds 1,526,252 shares of ASP Isotopes common stock, indicating that the sale represents a small portion of her overall equity position and is tied to a pre-arranged, tax-related mechanism rather than a discretionary reduction in holdings.
ASP Isotopes Inc. executive Donald George Ainscow, EVP, General Counsel and Secretary, reported an open-market sale of 100,000 shares of Common Stock. The weighted average sale price was $6.14 per share, with individual trades occurring between $6.11 and $6.17 per share.
Following this transaction, Ainscow directly holds 800,000 shares of ASP Isotopes Inc. common stock. The filing notes that detailed trade-by-trade pricing within the reported range is available upon request.
ASP Isotopes Inc. director Todd Wider sold 100,000 shares of Common Stock in open-market transactions. The Form 4 shows two sales of 50,000 shares each, at reported prices of $6.12 and $6.25 per share, executed as multiple trades within stated price ranges.
Footnotes explain that each reported price is a weighted average, with actual trade prices between $6.21 and $6.31 for one block and between $6.10 and $6.25 for the other. Overall, the filing reflects a net sale of 100,000 shares by the director.
ASP Isotopes Inc. director Michael Gorley sold 30,000 shares of Common Stock in an open-market transaction at a weighted average price of approximately $6.27 per share. After this sale, he directly holds 87,908 shares, indicating he retains a significant ongoing equity position.
According to the disclosure, the shares were sold in multiple trades at prices ranging from $6.10 to $6.63 per share, with the weighted average reported. The filing notes that full trade-by-trade pricing details are available upon request from the company, any stockholder, or the SEC staff.
ASP Isotopes Inc. COO Robert Ainscow reported selling 8,438 shares of common stock in open-market transactions at a weighted average price of $6.999 per share. According to the disclosure, these "sell to cover" trades were made under a Rule 10b5-1 trading plan adopted on June 9, 2025 to cover tax withholding obligations tied to vesting restricted stock awards, rather than discretionary sales. Following the transactions, Ainscow directly holds 2,281,879 ASP Isotopes shares.
ASP Isotopes Inc. Chairman and CEO Paul Elliot Mann reported both share sales and a new equity award. He sold a total of 251,275 shares of common stock in three open-market transactions at weighted average prices of $7.76, $7.88, and $8.29 per share. According to the disclosure, these were "sell to cover" trades under a Rule 10b5-1 plan to cover tax withholding on quarterly vesting of a restricted stock award. Mann also received a grant of 2,233,555 shares of common stock under his employment agreement, which will vest in four equal installments over a one-year period beginning on March 1, 2026.
Ainscow Robert reported acquisition or exercise transactions in this Form 4 filing.
ASP Isotopes Inc. Chief Operating Officer Robert Ainscow received an equity grant of 800,000 shares of common stock, awarded at a stated price of $0.0000 per share as compensation. Following this grant, he directly holds 2,290,317 common shares. The award will vest in semi-annual installments over four years, subject to applicable vesting conditions.
Ainscow Donald George reported acquisition or exercise transactions in this Form 4 filing.
ASP Isotopes Inc. executive vice president and general counsel Donald George Ainscow received an award of 400,000 shares of common stock as compensation. The filing shows he now holds 900,000 common shares directly. The award will vest in semi-annual installments over four years, subject to applicable vesting conditions beginning on the grant date.
ASP Isotopes Inc. reported that Chief Financial Officer Heather Kiessling acquired 840,000 shares of common stock through a stock award with a grant price of $0.0000 per share. Following this award, she holds a total of 1,549,376 common shares directly.
The award will vest in semi-annual installments over a four-year period, subject to applicable vesting conditions, meaning the shares are earned gradually over time rather than all at once.
ASP Isotopes Inc. COO Robert Ainscow reported an open-market sale of 22,500 shares of Common Stock at a weighted average price of $5.205 per share. According to the disclosure, this was a "sell to cover" transaction under a Rule 10b5-1 trading plan adopted on June 9, 2025 to cover tax withholding obligations tied to vesting restricted stock awards. After the sale, he directly held 1,490,317 shares, so the transaction represents a small portion of his overall position.
ASP Isotopes Inc. Chief Financial Officer Heather Kiessling reported an open-market sale of 23,124 shares of common stock on April 15, 2026 at a weighted average price of $5.478 per share. The footnotes state this was a "sell to cover" under a Rule 10b5-1 trading plan adopted on December 19, 2025 to cover tax withholding obligations tied to vesting restricted stock awards. After the sale, she directly holds 709,376 shares of ASP Isotopes common stock.
ASP Isotopes Inc. director Duncan Moore reported multiple stock transactions. He sold 11,642 shares of common stock at a weighted average price of $5.205 per share in an open-market trade. Following this sale, he directly owned 1,044,928 shares of ASP Isotopes common stock.
The filing also shows two earlier awards of restricted stock for his service as an independent director: 25,469 shares on November 12, 2025 and 36,548 shares on December 18, 2025, both granted at no cash cost. The sale on April 16, 2026 was executed under a Rule 10b5-1 trading plan adopted on December 31, 2025 and included shares sold to cover income tax liabilities from the vesting of a prior restricted stock award.
ASP Isotopes Inc. COO Robert Ainscow reported an open‑market sale of 25,000 shares of common stock on March 6, 2026. The sale was executed at a weighted average price of $4.511 per share, with individual trades ranging from $4.42 to $4.58.
These sales were made under a pre‑arranged Rule 10b5-1 trading plan adopted on December 13, 2024, indicating they were scheduled in advance. Following this transaction, Ainscow directly holds 1,512,817 shares of ASP Isotopes common stock.
ASP Isotopes Inc. COO Robert Ainscow reported an open-market sale of 8,438 shares of common stock. The transaction occurred on March 6, 2026 at a weighted average price of $5.439 per share.
The sale was a "sell to cover" under a Rule 10b5-1 trading plan adopted on June 9, 2025 to cover tax withholding obligations from vesting restricted stock awards. After this transaction, Ainscow directly owns 1,537,817 ASP Isotopes common shares.
ASP Isotopes Inc. Executive Chairman Paul Elliot Mann reported an open-market sale of 162,153 shares of common stock at a weighted average price of $5.436 per share. According to the disclosure, these were “sell to cover” transactions under a Rule 10b5-1 trading plan to satisfy tax withholding on the quarterly vesting of a restricted stock award.
After these sales, Mann held 7,597,385 shares of ASP Isotopes common stock directly. The filing notes the shares were sold in multiple transactions at prices ranging from $5.10 to $5.57 per share.
ASP Isotopes Inc. insider activity: The Interim CEO and COO reported selling 67,500 shares of common stock of ASP Isotopes Inc. on 11/17/2025 at a weighted average price of $7.507 per share. After this transaction, the executive beneficially owns 1,579,693 shares.
The filing explains that the sale was a "sell to cover" transaction made under a Rule 10b5-1 trading plan adopted on June 9, 2025, to cover tax withholding obligations tied to the vesting of restricted stock awards. The shares were sold in multiple trades at prices ranging from $7.215 to $7.85.
ASP Isotopes (ASPI) Form 4: Interim CEO and COO reported a sale of 22,500 shares of common stock on 10/14/2025 at a weighted average price of $13.599. The filing states these were “sell to cover” transactions executed under a Rule 10b5‑1 trading plan adopted on June 9, 2025 to cover tax withholding tied to vesting of restricted stock awards.
Trades occurred across multiple executions at prices ranging from $12.31 to $14.46. Following the transactions, the reporting person beneficially owns 1,647,193 shares directly.