RLI Corp underwrites property and casualty insurance through its subsidiaries. The company offers insurance coverage in the specialty admitted market, where the products are designed for special risks. It also offers products in the excess and surplus markets, which provides an alternative for customers with risks or loss exposures that generally cannot be written in the standard admitted market. RLI distributes property and casualty insurance through its wholly-owned branch offices that market to wholesale and retail producers. The company's insurance operation segments include Casualty, Property, and Surety and it derives a majority of its revenue from the Casualty segment.