Arthur J. Gallagher & Co. Director Retirement

Sherry Barrat has decided to retire from the Board of Directors of Arthur J. Gallagher & Co., effective May 12, 2026, at the 2026 Annual Meeting of Stockholders. She will not stand for re-election. Ms. Barrat's retirement is not due to any disagreements with the Company. Following her retirement, the size of the Board will be reduced from ten to nine members. The Company expresses gratitude for Ms. Barrat's service.