144 0001951275 XXXXXXXX LIVE 0001921865 ASP Isotopes Inc. 001-41555 2200 ROSS AVENUE SUITE 4575E DALLAS TX 75201 2144328219 Ainscow Robert OFFICER COMMON STOCK INDEPENDENT TRADING GROUP (ITG) INC.

33 YONGE STREET SUITE 420 TORONTO A6 M5E 1G4

8438 58137.82 125903447 06/08/2026 NASDAQ COMMON STOCK 09/06/2024 ACQUIRED AS COMPENSATION -- RESTRICTED STOCK AWARD ISSUER N 300000 09/06/2024 EQUITY COMPENSATION N Ainscow Robert

C/O ASP ISOTOPES INC. 2200 ROSS AVENUE, SUITE 4575E DALLAS TX 75201

COMMON STOCK 04/16/2026 22500 117112.50 The sale of shares reported in this Form 144 includes an amount for the purpose of satisfying the Reporting Person's income tax liabilities resulting from the quarterly vesting of a previously granted restricted stock award for 300,000 shares pursuant to an issuer equity incentive plan. The Aggregate Market Value of the shares to be sold is based on the closing market price of $6.89 on June 8, 2026. 06/08/2026 06/09/2025 /s/ Robert Ainscow