Diamondback Energy, Inc.

Trading Arrangements

None of the Company’s directors or officers adopted orterminated a Rule 10b5-1 trading arrangement or a non-Rule 10b5-1 trading arrangement during the Company’s fiscal quarter ended June 30, 2026.

Executive Retirement Policy

On August 1, 2026, the compensation committee (the “Compensation Committee”) of the board of directors of the Company adopted the Diamondback Energy, Inc. Executive Retirement Policy (the “Executive Retirement Policy”), effective as of August 1, 2026, to provide for certain payments and benefits upon the qualifying retirement of an eligible employee of the Company, Diamondback E&P LLC, or any other subsidiary or affiliate designated by the Compensation Committee, including the following named executive officers of the Company: Kaes Van’t Hof (Chief Executive Officer), Jere W. Thompson III (Chief Financial Officer), Teresa L. Dick (Executive Vice President of Accounting), Daniel Wesson (Chief Operating Officer) and Matt Zmigrosky (Chief Legal and Administrative Officer).

Pursuant to the Executive Retirement Policy, a qualifying retirement generally occurs when a participant voluntarily retires from employment on or after the date on which (i) the participant has attained at least 55 years of age, (ii) the sum of the participant’s age and years of employment equals or exceeds 65, and (iii) the participant has completed at least 10 years of employment; in addition, the participant must provide at least six months’ advance written notice of his or her retirement.

Upon a qualifying retirement, a participant will be entitled to:

•full accelerated vesting of all outstanding and unvested restricted stock units held by the participant that were granted on or after the effective date of the Executive Retirement Policy;

•continued eligibility to vest in all outstanding performance stock units held by the participant, based on actual achievement of applicable performance goals, for up to 12 months following the participant’s retirement date (or 24 months for participants with at least 15 years of employment);

•a prorated target annual bonus for the year in which the retirement date occurs; and

•a lump-sum cash payment equal to the participant’s monthly COBRA premium multiplied by the lesser of 18 and the number of months (including full and partial months) between the participant’s retirement date and the date on which the participant attains age 65.

The foregoing qualifying retirement payments and benefits are subject to the participant’s execution of a general release of claims and continued compliance with applicable restrictive covenants.

The foregoing description of the Executive Retirement Policy does not purport to be complete and is qualified in its entirety by reference to the text of the Executive Retirement Policy, a copy of which is filed as an exhibit to this report.