Hexcel (HXL) Proxy filing summary

Board of directors and corporate governance

• Thomas C. Gentile III, Chairman, CEO, and President, is standing for re-election at the Annual Meeting on May 14, 2026.

• Gentile was appointed as a director and compensation committee member of RPM International Inc. on April 20, 2026.

• Gentile currently serves on two public company boards and does not intend to join additional boards at this time.

Voting matters and shareholder proposals

• The supplement does not alter the proposals to be voted on at the Annual Meeting; all original proxy statement items remain unchanged.

Executive summary

• The supplement updates biographical information for Thomas C. Gentile III in advance of the 2026 Annual Meeting.

• No action is required from shareholders who have already submitted proxies unless they wish to change their vote.