Management Change/Compensation (Form 8-K)

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

As previously announced, effective October 1, 2025, Paul Mann, the founder, Chairman and Chief Executive Officer of ASP Isotopes Inc. (the "Company"), was appointed Executive Chairman of the Company and began taking a temporary leave of absence from his Chief Executive Officer duties for health reasons. In consultation with Mr. Mann, and effective October 1, 2025, the Company's Board of Directors (the "Board") appointed Robert Ainscow, the Company's Chief Operating Officer, to serve as Interim Chief Executive Officer (principal executive officer), in addition to his current duties.

In the Executive Chairman role, Mr. Mann has responsibility, working with the Interim Chief Executive Officer and the Board, for: the overall leadership and strategic direction of the Company; providing guidance and support to senior management of the Company; and the coordination of the activities of the Board. In the role of Interim CEO, Mr. Ainscow has the responsibility for managing the CEO's direct reports and communications with the Company's industry partners, shareholders and other important stakeholders, among other CEO duties.

Biographical and other information for Mr. Robert Ainscow is set forth in the Company's Annual Report on Form 10-K/A filed with the Securities and Exchange Commission on April 30, 2025 and is incorporated herein by reference. There is no arrangement or understanding between Mr. Robert Ainscow and any other persons pursuant to which he was selected as an officer. The Company has not entered into, amended, or modified any plan, contract, arrangement, grant, or award in connection with Mr. Robert Ainscow's appointment as Interim Chief Executive Officer.

Mr. Robert Ainscow is the brother of Donald Ainscow, who has served as Executive Vice President, General Counsel and Secretary since joining the Company in August 2025. Mr. Donald Ainscow is compensated according to the Company's standard practices, including participation in its employee benefit plans generally made available to employees of a similar responsibility level. His current base salary is $425,000 per annum and he is eligible to receive an annual bonus and equity awards as determined by the compensation committee. He received an initial grant of 400,000 shares of the Company's common stock pursuant to the Company's 2024 Inducement Equity Incentive Plan, which shall vest (subject to compliance with the applicable vesting conditions) in eight equal semi-annual installments over a four-year period. The compensation of Mr. Donald Ainscow was established by the Company in accordance with its compensation practices applicable to employees holding positions of a similar responsibility level and without the involvement of Mr. Robert Ainscow.