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Item 9A. Controls and Procedures

2026-04-10 compared with 2025-03-31 · 90 added, 20 removed, 134 unchanged (45% of the section changed)

5 unchanged sentences

Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgement in evaluating the cost-benefit relationship of possible controls and procedures.

Based on the evaluation of our disclosure controls and procedures as of December 31, 2024, our Chief Executive Officer and Chief Financial Officer concluded that, as a result of a material weakness identified in our internal control over financial reporting, our disclosure controls and procedures were not effective as of December 31, 2024 .

In the course of preparing the financial statements that are included in this Form 10-K, management has determined that a material weakness exists within the internal controls over financial reporting.

Based on the evaluation of our disclosure controls and procedures as of December 31, 2025, our Chief Executive Officer and Chief Financial Officer concluded that, as a result of material weaknesses identified in our internal control over financial reporting, our disclosure controls and procedures were not effective as of December 31, 2025 .

In the course of preparing the financial statements that are included in this Form 10-K, management has determined that material weaknesses exist within the internal controls over financial reporting.

The material weakness identified relates to the lack of formal control documentation and consistent execution of control procedures, and the lack of a sufficient complement of personnel within the finance and accounting function with an appropriate degree of knowledge, experience and training.

19 unchanged sentences

Other Information

Trading Arrangements of Section 16 Reporting Persons.

During the quarter ended December 31, 2025, the directors and officers of the Company (as defined in Rule

16a-1(f) of the Exchange Act) adopted or terminated the contracts, instructions, or written plans for the purchase or sale of our securities set forth in the table below.

Name and Title

Adoption/ Termination Date

Rule 10b5-1 (1)

Non-Rule 10b5-1 (2)

Total Number of Shares of Common Stock to be Sold (3)

Expiration Date

Heather Kiessling ( Chief Financial Officer )

December 19, 2025

April 14, 2027

Mann ( Chief Executive Officer and Executive Chairman )

December 30, 2025

March 3, 2027

Duncan Moore ( Director )

December 31, 2025

April 16, 2026

(1) Contract, instruction or written plan intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act.

(2) “Non-Rule 10b5-1 trading arrangement” as defined in Item 408(c) of Regulation S-K under the Exchange Act.

(3) Rule 10b5-1 trading arrangements that are intended to provide for “eligible sell-to-cover transactions” (as described in Rule 10b5-1(c)(1)(ii)(D)(3) under the Exchange Act) to satisfy tax withholding obligations arising exclusively from vesting of restricted stock awards (RSAs).

(4) The adoption of the Stock Sale Plan, dated December 30, 2025, by Mr.

Mann also terminated his Stock Sale Plan, dated December 13, 2024.

Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Directors, Executive Officers and Corporate Governance

The information required by this item will be included in an amendment to this Annual Report on Form 10-K or incorporated by reference from our definitive proxy statement to be filed pursuant to Rule 14A.

The information required by this item will be included in an amendment to this Annual Report on Form 10-K or incorporated by reference from our Proxy Statement to be filed pursuant to Regulation 14A within 120 days of the end of the fiscal year covered by this Annual Report on Form 10-K.

You can find our governance documents, including our corporate governance guidelines and our code of business conduct and ethics, on our website www.aspisotopes.com under “Investor - Governance - Governance Documents.” Our Board regularly reviews and updates our governance materials in light of legal and regulatory requirements, evolving best practices and other developments.

We intend to satisfy the disclosure requirement under Item 5.05 of Form 8-K regarding amendment to, or waiver from, a provision of our code of business conduct and ethics by posting such information on the website address and location specified above.

Executive Compensation

Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Certain Relationships and Related Transactions and Director Independence

Principal Accounting Fees and Services

Exhibits, Financial Statement Schedules

6 unchanged sentences

Description of Document

Firm Intention Letter Agreement, dated May 20,2025, by and between ASP Isotopes Inc.

and Renergen Limited (incorporated by reference to Exhibit 2.1 to the Form 8-K filed on May 20, 2025).

Letter Agreement, dated November 27, 2025, by and among ASP Isotopes Inc.

and Renergen Limited (incorporated by reference to Exhibit 2.1 to the Form 8-K filed on November 28, 2025).

Amended and Restated Certificate of Incorporation (incorporated by reference to Exhibit 3.3 to the Form S-1/A filed on November 9, 2022 (File No.

57 unchanged sentences

Registration Rights Agreement, dated as of June 5, 2024, by and among Quantum Leap Energy LLC and the Purchasers listed therein (incorporated by reference to Exhibit 10.2 to the Form 8-K filed on June 6, 2024).

Non-Employee Director Compensation Policy adopted effective October 30, 2024.

Non-Employee Director Compensation Policy adopted effective October 30, 2024 (incorporated by reference to Exhibit 10.31 to the Form 10-K filed on March 31, 2025).

Loan Agreement, dated May 19, 2025, by and among ASP Isotopes Inc., ASP Isotopes South Africa Proprietary Limited, as lender, and Renergen Limited, as borrower (incorporated by reference to Exhibit 10.1 to the Form 8-K filed on May 20, 2025).

Loan Agreement, dated May 16, 2025, by and between QLE TP Funding SPE LLC, as borrower, and TerraPower, LLC, as lender (incorporated by reference to Exhibit 10.1 to the Form 8-K filed on May 22, 2025).

ASP Isotopes Inc.

2025 Inducement Equity Incentive Plan and forms of award agreement thereunder (incorporated by reference to Exhibit 10.1 to the Form 10-Q filed on August 14, 2025).

Natrium Project Procurement Terms and Conditions – Enrichment Services by and between TerraPower, LLC and ASP Isotopes Inc., dated as of May 16, 2025 (incorporated by reference to Exhibit 10.3 to the Form 10-Q filed on August 14, 2025).

HALEU Long-Term Supply Agreement by and between TerraPower, LLC and ASP Isotopes Inc., dated as of May 16, 2025 (incorporated by reference to Exhibit 10.4 to the Form 10-Q filed on August 14, 2025).

Form of Convertible Note Purchase Agreement (including Form of Convertible Promissory QLE Note), by and among Quantum Leap Energy LLC and the Purchasers party thereto (incorporated by reference to Exhibit 10.1 to the Form 8-K filed on November 14, 2025).

Form of Registration Rights Agreement, by and among Quantum Leap Energy LLC and the Investors party thereto (incorporated by reference to Exhibit 10.2 to the Form 8-K filed on November 14, 2025).

Letter to the Term Loan Facility Agreement, dated November 27, 2025, by and among ASP Isotopes Inc., ASP Isotopes South Africa Proprietary Limited, as lender, and Renergen Limited, as borrower (incorporated by reference to Exhibit 10.1 to the Form 8-K filed on November 28, 2025).

Loan Agreement, between Industrial Development Corporation of South Africa Limited and Tetra4 Proprietary Limited, dated December 20, 2021.

Amendment, dated October 10, 2023, to Loan Agreement between Industrial Development Corporation of South Africa Limited and Tetra4 Proprietary Limited.

Amendment, dated September 1, 2025, to Loan Agreement between Industrial Development Corporation of South Africa Limited and Tetra4 Proprietary Limited.

Finance Agreement, between U.S.

International Development Finance Corporation, as successor in interest to Overseas Private Investment Corporation, and Tetra4 Proprietary Limited, dated August 20, 2019.

Amendment No.

1 to Finance Agreement, between United States.

International Development Finance Corporation and Tetra4 Proprietary Limited, dated March 30, 2020.

Amendment No.

2 to Finance Agreement, between United States.

International Development Finance Corporation and Tetra4 Proprietary Limited, dated April 28, 2020.

Amendment No.

3 to Finance Agreement, between United States.

International Development Finance Corporation and Tetra4 Proprietary Limited, dated February 26, 2021.

Amendment No.

4 to Finance Agreement, between United States.

International Development Finance Corporation and Tetra4 Proprietary Limited, dated August 24, 2021.

Amendment No.

5 to Finance Agreement, between United States.

International Development Finance Corporation and Tetra4 Proprietary Limited, dated December 16, 2021.

Amended And Restated Secured Term Loan Facility Agreement between Renergen Limited and the Standard Bank of South Africa Limited, dated December 12, 2025.

Series Seed-1 Preferred Stock Purchase Agreement, dated as of July 28, 2025, by and between IsoBio, Inc.

and ASP Isotopes Inc.

(incorporated by reference to Exhibit 10.1 to the Form 10-Q filed on November 19, 2025).

Investors’ Rights Agreement, dated as of July 28, 2025, by and among IsoBio, Inc.

and the Investors named therein (incorporated by reference to Exhibit 10.2 to the Form 10-Q filed on November 19, 2025).

Voting Agreement, dated as of July 28, 2025, by and among IsoBio, Inc., ASP Isotopes Inc.

and the Key Holders named therein (incorporated by reference to Exhibit 10.3 to the Form 10-Q filed on November 19, 2025).

Right of First Refusal and Co-Sale Agreement, dated as of July 28, 2025, by and among IsoBio, Inc.

ASP Isotopes Inc.

and the Key Holders named therein (incorporated by reference to Exhibit 10.4 to the Form 10-Q filed on November 19, 2025).

Second Amendment to Executive Employment Agreement between the registrant and Paul Mann dated April 5, 2024.

Insider Trading Policy.

17 unchanged sentences

Form 10-K Summary

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized, on the 31st day of March, 2025.

ASP Isotopes Inc.

Chairman, Chief Executive Officer and Director

Executive Chairman, Chief Executive Officer and Director

We, the undersigned directors and officers of ASP Isotopes Inc., hereby severally constitute Paul E.

2 unchanged sentences

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant in the capacities and on the dates indicated.

Chief Executive Officer, Chairman and Director (Principal Executive Officer)

March 31, 2025

Chief Executive Officer, Executive Chairman and Director (Principal Executive Officer)

April 10, 2026

/s/ HEATHER KIESSLING

Chief Financial Officer (Principal Financial and Accounting Officer)

March 31, 2025

April 10, 2026

Heather Kiessling

/s/ MICHAEL GORLEY, Ph.D.

March 31, 2025

April 10, 2026

Michael Gorley, Ph.D.

April 10, 2026

Ralph L Hunter, Jr.

April 10, 2026

/s/ DUNCAN MOORE, Ph.D.

March 31, 2025

April 10, 2026

Duncan Moore, Ph.D.

/s/ ROBERT RYAN

March 31, 2025

/s/ HENDRIK STRYDOM, Ph.D.

March 31, 2025

Hendrik Strydom, Ph.D.

April 10, 2026

/s/ TODD WIDER, M.D.

March 31, 2025

April 10, 2026

Todd Wider, M.D.

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 9A. Controls and Procedures