HF Sinclair (DINO) Proxy filing summary

Executive summary

• Supplement updates the proxy statement for the 2026 annual meeting scheduled for May 13, 2026, without altering proposals or board recommendations.

• CEO and President Timothy Go's employment ended on May 11, 2026, following a voluntary leave since February 17, 2026; Franklin Myers serves as interim CEO and President.

• Go's departure was amicable, with no disagreements regarding company operations, policies, or practices.

Executive compensation and say-on-pay

• Go receives a $4,735,000 separation payment in 12 monthly installments and continued group health plan participation at employee rates for 12 months, contingent on compliance with ongoing obligations.

• Partial vesting of 29,616 RSUs and conditional vesting of 163,609 PSUs granted, with PSUs subject to original performance criteria.

• Vesting and severance benefits are subject to Go's compliance with confidentiality, non-competition, and other continuing obligations.

Board of directors and corporate governance

• Franklin Myers, Board Chairperson, appointed as interim CEO and President effective February 17, 2026.

• Go resigned from all board and officer positions as of May 11, 2026.