Ironshore provides specialty lines of property and casualty insurance on a global basis, serving commercial clients through a broad network of multinational insurance brokers. Ironshore was initially capitalized in Bermuda with approximately $1 billion to support underwriting activities across a diverse set of specialty property and casualty markets. Through its platform in Bermuda, Ironshore writes property and excess casualty insurance for commercial risks. Ironshore's US operations write commercial property and casualty insurance, including a variety of coverages in the Management & Profesional Liability, Healthcare Liability, Construction, and Environmental specialty areas. Specialty coverages are underwritten at Lloyd's through Ironshore's Pembroke Syndicate 4000.

Calera Capital was a lead investor in the capitalization of Ironshore in January of 2007. To support its continued growth, Calera also participated in a subsequent $300 million equity raise in June of 2009.