PRESS RELEASE DETAIL


Dec 21, 2007

CoStar Group Awarded Patent for Field Research Technology

2005-05-19 2005 CoStar Group Awarded Patent for Field Research Technology

BETHESDA, MD -- CoStar Group, Inc. (NASDAQ: CSGP) today announced it has bee...

2005-05-19 2005 CoStar Group Awarded Patent for Field Research Technology

BETHESDA, MD -- CoStar Group, Inc. (NASDAQ: CSGP) today announced it has been awarded a patent by the United States Patent and Trademark Office for critical elements of its proprietary field research technology.

U.S. Patent No. 6,871,140 recognized CoStar's innovation in developing mobile information gathering systems to collect comprehensive commercial real estate information in the field. The Company's custom-designed fleet of mobile research facilities is equipped with remote computers that utilize global positioning system technology to identify nearby buildings in its database. The remote system automatically prompts researchers to update information related to the property as well as add any missing information. By automatically identifying properties missing from the database, CoStar is able to provide the most thorough, accurate and timely information for its customers.

"CoStar's reputation for developing innovative technology and productivity tools is well known among the over 50,000 commercial real estate professionals in the United States and United Kingdom that rely on our services," stated CoStar Group President & CEO Andrew C. Florance. "However, the technology in use behind the scenes by our 700 researchers and field researchers is equally groundbreaking."

CoStar maintains the largest researched database of over 1 million commercial real estate properties, including over 462,000 extensively researched and photographed properties and over 2.2 million digital images. CoStar researchers drove more than 1.3 million miles and added over 238,500 building photographs -- 4,606 per week -- to the database in 2004.

About CoStar Group, Inc.

CoStar Group, Inc., (NASDAQ: CSGP) is the leading provider of information services to commercial real estate professionals in the United States and the United Kingdom. CoStar's suite of services offers customers access via the Internet to the most comprehensive database of commercial real estate information on over 55 U.S. markets, London and the United Kingdom. Based in Bethesda, MD, the company has approximately 1,000 employees throughout the United States and the United Kingdom, including the largest professional research organization in the industry.

This news release includes "forward-looking statements" including, without limitation, statements regarding CoStar's expectations, beliefs, intentions or strategies regarding the future. These statements are subject to many assumptions, risks and uncertainties that could cause actual results to differ materially from those expressed or implied in the forward-looking statements. More information about potential factors that could cause actual results to differ materially from those discussed in the forward-looking statements include, but are not limited to, those stated in CoStar's filings from time to time with the Securities and Exchange Commission, including CoStar's Form 10-Q for the period ended March 31, 2005, under the heading "Risk Factors." All forward-looking statements are based on information available to CoStar on the date hereof, and CoStar assumes no obligation to update such statements.
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