Lexington Insurance Company is a surplus lines insurance company wholly owned by AIG. It is the largest surplus lines insurer based in the U.S., and it offers property, casualty, and specialty lines insurance products. Started in 1965 with four people and $3 million in gross written premium from its property-casualty business, Lexington was one of the first U.S. insurers formed to specialize in writing surplus lines coverage. In 1971, Lexington expanded, establishing an office in London. By the 1990s, the company had further grown, establishing programs, healthcare, and catastrophe excess liability divisions.