CSGP

Costar Group, Inc.

A maker of online real estate marketplaces and data tools, CoStar Group runs well-known sites like CoStar, LoopNet, Apartments.com, Homes.com, and Matterport, which agents, brokers, and property managers use to list, find, and tour properties. Founder Andy Florance started the business in 1987 in the Washington, D.C. area after realizing commercial real estate had almost no organized data compared to stock markets. A fun quirk: the name is a mashup of "computerized" and "star," and the firm grew through big acquisitions like Matterport and the British site OnTheMarket.