Form 144 report of proposed sale of securities

The announcement

Form 144 – report of proposed sale of securities

ASP ISOTOPES INC.
(Incorporated in the State of Delaware,
United States of America)
(Delaware file number 6228898)
Ticker Symbol: NASDAQ: ASPI
ISIN: US00218A1051
LEI: 6488WHV94BZ496OZ3219
JSE Share Code: ISO
("ASPI" or "the Company")

FORM 144 – REPORT OF PROPOSED SALE OF SECURITIES

ASPI stockholders are advised that on 25 September 2026, a Form 144 has been filed with the U.S.
Securities and Exchange Commission.

A copy of the Form 144 can be found at: Form 144

The Company has a primary listing on the Nasdaq and a secondary listing on the Main Board of the JSE.

28 September 2026

Sponsor
Valeo Capital Proprietary Limited
Date: 28/09/2026 08:00:00
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