PRESS RELEASE DETAIL


Jan 04, 2008

CoStar Group, Inc. Announces the Completion of an Underwritten Offering by Certain of its Stockholders

2000-08-15 2000 CoStar Group, Inc. Announces the Completion of an Underwritten Offering by Certain of its Stockholders

Bethesda, MD -- CoStar Group, I...

2000-08-15 2000 CoStar Group, Inc. Announces the Completion of an Underwritten Offering by Certain of its Stockholders

Bethesda, MD -- CoStar Group, Inc. (Nasdaq: CSGP), http://www.costargroup.com, the Internet based, leading provider of information services to the U.S. commercial real estate industry, today announced that certain of its stockholders completed an underwritten offering led by Donaldson, Lufkin & Jenrette Securities Corporation. The selling stockholders sold a total of 956,500 shares of common stock in the offering at a price of $28.00 per share. CoStar Group did not sell any shares in the offering and will not receive any proceeds from this offering.

Copies of the prospectus and the prospectus supplement can be obtained from Donaldson, Lufkin & Jenrette Securities Corporation, 277 Park Avenue, New York, NY, 10172.

About CoStar Group, Inc.

Headquartered in Bethesda, MD, CoStar Group, Inc. is the leading provider of information services to the U.S. commercial real estate industry. CoStar's suite of products offers customers access via the Internet to the most comprehensive, verified database of commercial real estate information in over 50 U.S. markets. The company has more than 1,000 employees and contractors nationally, including over 700 highly trained commercial real estate research professionals in 27 offices.

This news release includes "forward-looking statements," which involve many risks and uncertainties that could cause actual results to differ materially from these statements. Important factors that could cause actual results to differ materially include, but are not limited to, those listed in CoStar's Form 10-K for the year ended December 31, 1999 and its Registration Statement on Form S-3 filed on June 16, 2000.
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