Alleghany

RANK339

Alleghany moved up 12 spots on the Fortune 500 this year. The New York City-based company owns subsidiaries such as Transatlantic Holdings Inc., a global reinsurer; RSUI Group, Inc., which underwrites wholesale specialty insurance coverages; and CapSpecialty Inc., an underwriter of commercial property, casualty, and surety insurance coverages. For the first quarter of 2021, the company reported that net premiums written increased 14%, with reinsurance up 15.2% and insurance 11.5% higher.