HF Sinclair Corp

(Former name or former address, if changed since last report)

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Item 1.01 Entry into a Material Definitive Agreement.

HF Sinclair Corporation (the “Company”) entered into a Stock Purchase Agreement, dated October 29, 2026 (the “Stock Purchase Agreement”), with REH Advisors Inc. (the “Selling Stockholder” or “REH”) (now the parent company of REH Company, LLC (formerly known as The Sinclair Companies)), pursuant to which the Company agreed to repurchase from the Selling Stockholder 2,350,000 shares of the Company’s outstanding common stock, par value $0.01 per share (the “Common Stock”), in a privately negotiated transaction. The price per share to be paid by the Company under the Stock Purchase Agreement is $109.37 per share resulting in an aggregate purchase price of approximately $257 million. The purchase price will be funded with cash on hand and is expected to be completed on or around November 3, 2026. The Stock Purchase Agreement contains customary representations, warranties and covenants of the parties. The shares to be repurchased under the Stock Purchase Agreement will be held as treasury stock by the Company. This share repurchase is the twenty-third privately negotiated transaction between the Company and the Selling Stockholder and will be made pursuant to the Company’s Share Repurchase Program described below. The foregoing description of the Stock Purchase Agreement does not purport to be complete and is qualified in its entirety by reference to the Stock Purchase Agreement, a copy of which is filed herewith as Exhibit 10.1 and is incorporated by reference herein.

The share repurchase described above will be made pursuant to the Company’s previously disclosed $1.5 billion share repurchase program authorized by the Board of Directors (the “Board”) of the Company on August 26, 2026 (the “Share Repurchase Program”). To date, the Company has repurchased $766 million in Common Stock under the Company’s Share Repurchase Program, which is inclusive of the share repurchase described above, and has approximately $734 million authorization remaining under the Share Repurchase Program. The timing and amount of future share repurchases under the Company’s Share Repurchase Program, including any additional repurchases from REH, will depend on market conditions and corporate, tax, regulatory and other relevant considerations. The Share Repurchase Program may be discontinued at any time by the Board.

Under the Stockholders Agreement, dated as of August 2, 2021 (as may be amended from time to time, the “Stockholders Agreement”), among the Company, REH and the stockholders set forth therein (the “REH Parties”), the REH Parties have the right to designate one person for election or appointment to the Board (the “REH Designee”) for so long as the REH Parties beneficially own less than 15% but at least 5% of all Common Stock of the Company (the “Designation Threshold”). Following the share repurchase described above, the REH Parties are expected to beneficially own less than the Designation Threshold. Pursuant to the terms of the Stockholders Agreement, if the REH Parties remain below the Designation Threshold on January 13, 2027, the REH Designee must offer to resign from the Board within 30 days thereafter. The Board will determine, in its sole discretion, whether to accept or reject such resignation. For more information on the Selling Stockholder’s relationship to the Company, please refer to the Company’s Definitive Proxy Statement on Schedule 14A filed with the Securities and Exchange Commission (the “SEC”) on March 31, 2026.