Oklo Inc.

Rule 10b5-1 Trading Arrangements

Except as stated below, no director or officer (as defined in Rule 16a-1(f) under the Exchange Act) of the Company adopted, modified, orterminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408 of Regulation S-K, during the three months ended June 30, 2026.

On April 2, 2026, William Goodwin, the Company’s Chief Legal and Strategy Officer, materially modified the Rule 10b5-1 trading arrangement previously adopted by him on December 15, 2025 and previously disclosed in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025 (the “Prior Trading Arrangement”). The Prior Trading Arrangement was 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 the vesting of equity awards and the related issuance of up to 13,620 shares of the Company’s common stock, and was scheduled to terminate on December 4, 2026, subject to early termination for certain specified events set forth therein.

For purposes of Rule 10b5-1(c) under the Exchange Act, the April 2, 2026 modification constituted atermination of the Prior Trading Arrangement and the adoption of a new Rule 10b5-1 trading arrangement (the “Modified Trading Arrangement”) intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act. The Modified Trading Arrangement provided for the sale of up to 79,677 shares of the Company’s common stock and was scheduled to terminate on December 4, 2026, subject to early termination for certain specified events set forth therein. On June 29, 2026, Mr. Goodwin terminated the Modified Trading Arrangement.