HF Sinclair Corporation

Marchant Matthew H (Last) (First) (Middle) 2323 VICTORY AVENUE SUITE 1400 (Street) DALLAS TEXAS 75219 (City) (State) (Zip) UNITED STATES (Country) 2. Date of Event Requiring Statement (Month/Day/Year) 08/03/2026 3. Issuer Name and Ticker or Trading Symbol HF Sinclair Corp [ DINO ] 3a. Foreign Trading Symbol 5. If Amendment, Date of Original Filed (Month/Day/Year) 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) SVP and General Counsel 6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person Table I - Non-Derivative Securities Beneficially Owned 1. Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Stock 3,582 (1) D Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 4) 2. Date Exercisable and Expiration Date (Month/Day/Year) 3. Title and Amount of Securities Underlying Derivative Security (Instr. 4) 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 6. Nature of Indirect Beneficial Ownership (Instr. 5) Date Exercisable Expiration Date Title Amount or Number of Shares Explanation of Responses: 1. Restricted stock units granted under the HF Sinclair Corporation Amended and Restated 2020 Long Term Incentive Plan, of which 1,843 will vest on December 1, 2026, 1,213 will vest on December 1, 2027, and 526 will vest on December 1, 2028, provided that the reporting person remains in the employ of the Issuer through each such vesting date. The vested restricted stock units will be paid within 30 days following the vesting date in the form of the Issuer's common stock equal to the number of vested restricted stock units. Harrison Morris Attorney-in-Fact for Matthew H. Marchant 08/05/2026 ** Signature of Reporting Person Date Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. * If the form is filed by more than one reporting person, see Instruction 5 (b)(v). ** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a). Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure. Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number. * Form 3: SEC 1473 (03-26) filed an initial statement of beneficial ownership (Form 3) as a Director of DINO, with an event date of 1473. The filer directly owns 3,582 shares of common stock. This is a routine insider-ownership disclosure with no indication of open-market purchases or activist intent.

DINO filed an 8-K (Item 1.01) disclosing entry into a material definitive agreement. The filing describes: entered into a Stock Purchase Agreement, dated August 2, 2026 (the “Stock Purchase Agreement”), with REH Advisors Inc. Key financial terms include $0.01 . Material definitive agreements are significant corporate commitments and may be transformative depending on scope.

A reporting person filed a amended Schedule 13D disclosing beneficial ownership of a disclosed percentage of DINO's outstanding shares. A Schedule 13D signals a potentially activist or strategic stake above the 5% reporting threshold.

HF Sinclair's (DINO) Executive Vice President and General Counsel Eric Nitcher notified the Board on July 27, 2026 that he is retiring from his executive officer role effective July 31, 2026. Nitcher will remain an employee through year-end 2026 to facilitate an orderly transition, serving in an advisory capacity. His successor has not yet been named and his retirement was not related to any disagreement with the company or Board. This is an administrative officer departure announcement; routine counsel-level transition.

HF Sinclair Corporation (DINO) reported Q2 2026 financial results on July 28, 2026 via press release and investor presentation furnished as exhibits. No headline figures appear in the filing body. This is a standard quarterly earnings disclosure for an independent petroleum refiner and marketer; throughput volumes, refining margins, and refined product segment results are in the attached exhibits.

Kunneman Dale filed an initial Form 3 as a 10%+ owner of DINO, disclosing initial beneficial ownership of securities as of the event date. This is a standard Section 16 reporting obligation triggered by the relationship with the issuer. Routine administrative filing with no indication of open-market transactions.

White Scott Stephen filed an initial Form 3 as a 10%+ owner of DINO, disclosing initial beneficial ownership of securities as of the event date. This is a standard Section 16 reporting obligation triggered by the relationship with the issuer. Routine administrative filing with no indication of open-market transactions.

Kaysen Eric filed an initial Form 3 as a 10%+ owner of DINO, disclosing initial beneficial ownership of securities as of the event date. This is a standard Section 16 reporting obligation triggered by the relationship with the issuer. Routine administrative filing with no indication of open-market transactions.