Mains Stephanie K. 4

What Happened
Stephanie K. Mains, a non-employee director of Diamondback Energy, received a grant of 982 restricted stock units (RSUs) on 2026-05-20. The Form 4 reports an acquisition (transaction code A) at $0.00 per share (awarded, not purchased), total reported value $0 on the filing date. This is a compensation award rather than an open-market purchase or sale.

Key Details

• Transaction date and type: 2026-05-20 — Award/Grant of 982 RSUs (code A).
• Reported price: $0.00 per unit; total reported acquisition value $0 (award).
• Vesting: RSUs vest on the earlier of the one-year anniversary of the grant or the 2027 annual meeting of stockholders (per footnote).
• Shares owned after transaction: Not disclosed in the supplied filing details.
• Filing timeliness: Form filed 2026-05-21 for a 2026-05-20 transaction — within the typical Section 16 reporting window (timely).
• Footnote: RSUs represent a contingent right to receive one common share each upon vesting.

Context
RSU grants to non-employee directors are routine compensation and don't reflect an immediate purchase or sale. These RSUs will convert to actual shares only if and when they vest under the stated schedule, at which point tax withholding or other withholding-related share transfers may occur and be reported separately.