X0306 4 2021-03-17 1 0001108827 QEP RESOURCES, INC. QEP 0001678505 Cutt Timothy J. 1050 17TH STREET, SUITE 800 DENVER CO 80265 1 1 0 0 President & CEO Common Stock 2021-03-17 4 D 0 970597 D 0 D Phantom Stock Units 2021-03-17 4 D 0 1599972 D Common Stock 1599972 0 D This amount includes 681,474 shares of common stock of QEP Resources, Inc. ("QEP") subject to restricted stock awards. On March 17, 2021, pursuant to the Agreement and Plan of Merger dated as of December 20, 2020 (the "Merger Agreement"), by and among Diamondback Energy, Inc. ("Diamondback"), Bohemia Merger Sub Inc., a wholly owned subsidiary of Diamondback ("Merger Sub"), and QEP, Merger Sub merged with and into QEP (the "Merger") with QEP surviving the Merger as a wholly-owned subsidiary of Diamondback. Pursuant to the Merger Agreement, each share of QEP common stock issued and outstanding immediately prior to the effective time of the Merger (the "Effective Time") (subject to certain exceptions) was converted into the right to receive 0.05 shares of Diamondback common stock (the "Exchange Ratio"). Pursuant to the Merger Agreement, at the Effective Time, any shares of QEP common stock subject to restricted stock awards were converted into a number of time-based restricted shares of Diamondback common stock (rounded to the nearest whole share) equal to the product of (i) the total number of shares of QEP common stock subject to such award immediately prior to the Effective Time multiplied by (ii) the Exchange Ratio. Pursuant to the Merger Agreement, at the Effective Time, each unvested award of performance share units denominated in shares of QEP common stock that was outstanding immediately prior to the Effective Time was converted into time-based restricted stock units in respect of that number of shares of Diamondback common stock (rounded to the nearest whole share) equal to the product of (i) the number of shares of QEP common stock subject to such award immediately prior to the Effective Time that would have been earned under the applicable terms of such award based upon the higher of (A) 100% of the target level of performance and (B) actual performance through the closing date (as determined by the compensation committee of QEP's board of directors) multiplied by (ii) the Exchange Ratio. /s/ Timothy J. Cutt 2021-03-17