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BETHESDA, Md., Oct. 9, 2009 -- CoStar Group, Inc. (Nasdaq:CSGP - News), the number one provider of information, marketing and analytic services to the commercial real estate industry, will announce financial results for the third quarter of 2009 following the market close on Wednesday, October 21, 2009. Management will conduct a conference call to discuss the third quarter results and the company's outlook for the fourth quarter at 11:00 AM EDT on Thursday, October 22, 2009.

To participate in the conference call, please dial (800) 288-8976 (from the United States and Canada) or (612) 332-0335 (from all other countries) and refer to conference code 118413. Investors may also listen to an audio web cast of this conference call by accessing the link in the Investors section of CoStar's web site at www.CoStar.com/investors.aspx 

An audio recording of the conference will be available for replay approximately one hour after the call's completion and remain available through midnight on November 5, 2009. To access the recorded call, please dial (800) 475-6701 (from the U.S. and Canada) or (320) 365-3844 (from all other countries) using access code 118413. The webcast replay will also be available in the Investors section of CoStar Group's web site for a period of time following the call.

About CoStar Group, Inc. 

CoStar Group, Inc. (Nasdaq:CSGP - News) is the number one provider of information, marketing and analytic services to commercial real estate professionals in the United States as well as the United Kingdom. CoStar's suite of services offers customers access via the Internet to the most comprehensive database of commercial real estate information throughout the U.S. as well as in the United Kingdom and France. Headquartered in Bethesda, MD, CoStar has approximately 1,400 people working for the company worldwide, including the largest professional research organization in the industry. For more information, visit http://www.costar.com.