Arthur J. Gallagher & Co. AJG

What this company does

Arthur J. Gallagher & Co. and its subsidiaries are engaged in providing insurance brokerage, reinsurance brokerage, consulting, and third-party property/casualty claims settlement and administration services to entities and individuals around the world. It had a market capitalization at December 31, 2025 of approximately $67 billion. It reports its results in three segments -- brokerage, risk management and corporate -- and the brokerage and risk management segments contributed approximately 87% and 13%, respectively, to 2025 revenues. It offers client service capabilities in approximately 130 countries around the world through direct operations as well as through a network of correspondent brokers and consultants. It manages its third party claims adjusting operations through a network of more than 40 offices located throughout Australia, Canada, New Zealand, the U.K. and the U.S. Its reinsurance brokerage operations, referred to as Gallagher Re, accounted for 12% of its brokerage segment revenues in 2025 and operate from more than 77 offices across 27 countries, with specialist expertise underpinned by analytics capabilities including catastrophe modeling, dynamic financial analysis, rating agency analysis and capital modeling. Since its founding in 1927, Gallagher has grown from a one-person insurance agency. It was reincorporated as a Delaware corporation in 1972.

Written from the business description in ARTHUR J. GALLAGHER & CO.'s annual report to the U.S. Securities and Exchange Commission, filed 17 February 2026. Every sentence was checked against that document before publication.