CoStar Group sues LoopNet

Feb 5 (Reuters) - CoStar Group Inc (CSGP.O), a provider of real estate information services, said it filed a lawsuit against LoopNet Inc (LOOP.O) questioning the company's claim on the number of its registered users.

As of November 2007, LoopNet, a real estate Web site operator, claimed to have 2.5 million registered members, CoStar said in a statement. (Reporting by Swagata Gupta in Bangalore; Editing by Anupama Dwivedi) ((swagata.gupta@reuters.com; within U.S. +1 646 223 8780; outside U.S. +91 80 4135 5800; Reuters Messaging: swagata.gupta.reuters.com@reuters.net))