X0202 SCHEDULE 13D/A 0002027139 XXXXXXXX LIVE 28 Common Stock 08/02/2026 false 0001915657 403949100 HF Sinclair Corporation

2323 Victory Avenue Suite 1400 Dallas TX 75219

REH Advisors Inc. (801) 524-2752 Attn: General Counsel 2800 West Lincolnway Cheyenne WY 82009 David P. Oelman (713) 758-2222 Vinson & Elkins LLP 845 Texas Avenue, Suite 4700 Houston TX 77002 Michael S. Telle (713) 758-2222 Vinson & Elkins LLP 845 Texas Avenue, Suite 4700 Houston TX 77002 0002027139 N REH Advisors Inc. OO N WY 0 8881662 0 8881662 8881662 N 5.1 CO * Calculation of percentage based on a total of 177,783,849 shares of Common Stock (as defined below) outstanding as of July 24, 2026, as reported by the Issuer (as defined below) in its Quarterly Report on Form 10-Q, filed with the Securities and Exchange Commission (the "SEC") on July 30, 2026, less the Common Stock acquired by the Issuer pursuant to the Twenty-Third Repurchase Transaction (as defined below). (1) The Reporting Person is the primary and direct beneficial owner of the 8,881,662 shares indicated above, and the board of directors of the Reporting Person has all voting and investment power with respect to such shares. Common Stock HF Sinclair Corporation 2323 Victory Avenue Suite 1400 Dallas TX 75219 This Amendment No. 28 (this "Amendment") supplements the information set forth in the Schedule 13D originally filed by REH Company (f/k/a The Sinclair Companies), a Wyoming corporation (the "Reporting Person"), and Carol Orme Holding (who has ceased to be a reporting person) with the SEC, as amended from time to time (the "Schedule 13D"), relating to the common stock, par value $0.01 per share ("Common Stock"), of HF Sinclair Corporation, a Delaware corporation (the "Issuer"). The information set forth in response to each separate Item below shall be deemed to be a response to all Items where such information is relevant. The Schedule 13D is hereby supplementally amended as follows: The information contained in the explanatory note and Items 3 and 6 of the Schedule 13D is incorporated herein by reference. On August 2, 2026, the Issuer entered into a Stock Purchase Agreement (the "Twenty-Second Purchase Agreement") with the Reporting Person to repurchase 2,375,000 shares of Common Stock, for $89.41 per share, for the aggregate purchase price of $212,348,750 in a privately negotiated transaction (the "Twenty-Third Repurchase Transaction"). The Twenty-Third Repurchase Transaction is expected to close on or about August 5, 2026, subject to customary closing conditions. The foregoing description of the Twenty-Second Purchase Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Twenty-Second Purchase Agreement, which is filed as Exhibit 10.24 hereto and is incorporated herein by reference. As previously reported, the Reporting Person has sold its Common Stock from time to time in both open market sales and sales to the Issuer. Subject to the terms of the Stockholders Agreement, the Reporting Person may engage in such sales (with a strong preference for sales to the Issuer), but the Reporting Person may both acquire additional Common Stock or dispose of any or all of the Common Stock, in each case, depending upon an ongoing evaluation of the investment in the Common Stock, prevailing market conditions, other investment opportunities, other investment considerations and/or other factors. The Reporting Person evaluates its investments in the Common Stock on a continual basis. Additionally, while the Reporting Person reserves the right to make sales from time to time, it is its intent as of the date of this Amendment to maintain such sufficient ownership of Common Stock so the Reporting Person retains the right to appoint at least one director to the Board of the Issuer pursuant to the Stockholders Agreement. The Reporting Person may, at any time and from time to time, review or reconsider such position. (a.) - (b.) The aggregate number and percentage of Common Stock beneficially owned by the Reporting Person (on the basis of a total of 177,783,849 shares of Common Stock outstanding as of July 24, 2026, as reported in the Issuer's Quarterly Report on Form 10-Q, filed with the SEC on July 30, 2026, less the Common Stock acquired by the Issuer pursuant to the Twenty-Third Repurchase Transaction) are as follows: A. REH Advisors Inc. i. Amount beneficially owned: 8,881,662 Percentage: 5.1% a. Sole power to vote or to direct the vote: 0 b. Shared power to vote or to direct the vote: 8,881,662 c. Sole power to dispose or to direct the disposition of: 0 d. Shared power to dispose or to direct the disposition of: 8,881,662 To the best knowledge of the Reporting Person, no transactions were effected by the Reporting Person during the past 60 days other than the transactions described herein. No other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, any of the Common Stock beneficially owned by the Reporting Person, other than as described herein. Not applicable. The information contained in the explanatory note and Items 3 and 4 of the Schedule 13D is incorporated herein by reference. Exhibit 10.24 Stock Purchase Agreement, dated as of August 2, 2026, by and among HF Sinclair Corporation and REH Advisors Inc. REH Advisors Inc. /s/ Ross B. Matthews 08/04/2026