SCHEDULE 13D/A 0002021433 XXXXXXXX LIVE 4 Class A Common Stock, par value $0.0001 per share 06/30/2025 false 0001849056 02156V109 Oklo Inc.

3190 Coronado Drive Santa Clara CA 95054

Jacob DeWitte, c/o Oklo Inc. (844) 200-3276 3190 Coronado Drive Santa Clara CA 95054 0002021433 N Jacob DeWitte OO N X1 0.00 23907206.00 0.00 23907206.00 23907206.00 N 16.2 IN 0002021786 N Caroline Cochran OO N X1 0.00 23907206.00 0.00 23907206.00 23907206.00 N 16.2 IN Class A Common Stock, par value $0.0001 per share Oklo Inc. 3190 Coronado Drive Santa Clara CA 95054 This Amendment No. 4 to Schedule 13D (this "Amendment No. 4") amends and supplements the statement on Schedule 13D filed with the United States Securities and Exchange Commission on May 16, 2024 (as amended to date, the "Schedule 13D"), relating to the Class A common stock, par value $0.0001 per share (the " Class A Common Stock"), of Oklo Inc., a Delaware corporation (the "Issuer"). Capitalized terms used herein without definition shall have the meaning set forth in the Schedule 13D. Item 5 of the Schedule 13D is hereby amended and restated in its entirety as follows: The information contained on the cover pages is incorporated by reference to this Item 5. The Reporting Persons may be deemed to beneficially own an aggregate of 23,907,206 shares of Class A Common Stock, representing 16.2% of the Class A Common Stock outstanding based upon 147,380,826 shares of Class A Common Stock outstanding as of June 13, 2025, as set forth in the Issuer's Prospectus Supplement filed with the Securities and Exchange Commission on June 13, 2025. The information contained on the cover pages is incorporated by reference to this Item 5. The amounts reflected in the cover pages consist of (i) 10,105,098 shares of Class A Common Stock held of record by Mr. DeWitte, (ii) 9,802,108 shares of Class A Common Stock held of record by Ms. Cochran; (iii) 2,000,000 shares of Class A Common Stock held of record by Mr. DeWitte's GRAT; and (iv) 2,000,000 shares of Class A Common Stock held of record by Ms. Cochran's GRAT. The amounts reported herein do not include any vested RSUs which are not expected to settle within 60 days of the date of this filing. Mr. DeWitte and Ms. Cochran are married and, as a result, may be deemed to share beneficial ownership of each other's securities. On May 29, 2025, the Reporting Persons gifted an aggregate of 200,000 shares of Class A Common Stock for no consideration. On June 24, 2025, the Reporting Persons gifted an aggregate of 600,000 shares of Class A Common Stock for no consideration. On June 30, 2025, the Reporting Persons disposed of an aggregate of 600,000 shares of Class A Common Stock at a weighted average price of $55.1973 per share in a series of open-market transactions pursuant to their 10b5-1 Trading Plan entered into on March 31, 2025. The Reporting Persons undertake to provide, upon request by the staff of the SEC, the Issuer, or a security holder of the Issuer, full information regarding the number of shares sold at each separate price for each transaction. None. Not applicable. Jacob DeWitte /s/ Richard Craig Bealmear 07/02/2025 Caroline Cochran /s/ Richard Craig Bealmear 07/02/2025