ASP Isotopes CEO Paul Mann Receives 2.23M Shares and Sells 251K Shares Under 10b5-1 Plan

This Form 4 filing reports significant stock transactions by Paul Mann, Chairman and CEO of ASP Isotopes Inc. On May 28, 2026, Mann received 2,233,555 shares of common stock as part of a restricted stock award under his employment agreement, which will vest in four equal installments over one year beginning March 1, 2026. Subsequently, on June 1-3, 2026, Mann sold 83,758, 83,758, and 83,759 shares respectively (total 251,275 shares) at weighted average prices of $7.88, $8.29, and $7.76 per share. These sales were executed under a Rule 10b5-1 trading plan adopted on December 30, 2025, and were described as "sell to cover" transactions to cover tax withholding obligations related to quarterly vesting of restricted stock awards. Following these transactions, Mann's total holdings decreased from 9,830,940 to 9,579,845 shares. The filing indicates all transactions were properly executed under a pre-established trading plan.