PRESS RELEASE DETAIL


Apr 29, 2011

CoStar Group's HQ Acquisition Named Best Real Estate Deal-Urban Office Sale of 2010 by Washington Business Journal

WASHINGTON, April 29, 2011 -- CoStar Group, Inc. (Nasdaq:CSGP) today announced its 2010 acquisition of 1331 L Street NW was recognized as the Best Real Estate Deal-Urban Office Sale of 2010 by the Washington Business Journal in the Urban Office Sale category. The award was presented in an awards dinner last night at the Mayflower Renaissance.

WASHINGTON, April 29, 2011 -- CoStar Group, Inc. (Nasdaq:CSGP) today announced its 2010 acquisition of 1331 L Street NW was recognized as the Best Real Estate Deal-Urban Office Sale of 2010 by the Washington Business Journal in the Urban Office Sale category. The award was presented in an awards dinner last night at the Mayflower Renaissance.

CoStar acquired the 169,429-square-foot office building in February 2010 for $41.3 million from Mortgage Bankers Association and moved its corporate headquarters from Bethesda, MD, to Washington, DC. CoStar was able to buy the space for $243 per square foot, less than half of the market rate average of $518 per square foot at the time.  

"Our massive research operations, industry leading market analysis and quantitative forecasting models give us unique intelligence into the trends driving commercial real estate," stated CoStar Group President & CEO Andrew C. Florance. "We were able to capitalize on that market intelligence to secure a great building and reduce our long-term occupancy costs."

CoStar was able to take advantage of its powerful market intelligence again in February 2011 when it sold 1331 L Street NW to an affiliate of Munich-based GLL Real Estate Partners GmbH for aggregate consideration of $101 million in a sale-leaseback.

"It wasn't luck, we used market insight very effectively when we purchased our headquarters in Washington and sold it a year later for more than twice what we paid for it," added Florance. "We were able to capitalize on the recovery in investment grade real estate before the average investor was aware of it."

"These transactions demonstrate the value our high-end institutional forecasting and analytical tools provide to owners and institutional investors," Florance added. "They are a key part of our strategic roadmap and will continue to receive significant ongoing investment."

John Benziger of Lincoln Property Co. represented CoStar in the 2010 acquisition, and Womble Carlyle Sandridge & Rice PLLC served as its legal advisor. Stephen Conley, John Duffy, Andrew Weir and Elizabeth Taylor of Holiday Fenoglio Fowler LP represented the Mortgage Bankers Association.

About CoStar Group, Inc.
CoStar Group (Nasdaq:CSGP) is commercial real estate's leading provider of information and analytic services. Founded in 1987, CoStar conducts expansive, ongoing research to produce and maintain the largest and most comprehensive database of commercial real estate information. Our suite of online services enables clients to analyze, interpret and gain unmatched insight on commercial property values, market conditions and current availabilities. Headquartered in Washington, DC, CoStar maintains offices throughout the U.S. and in Europe with a staff of approximately 1,500 worldwide, including the industry's largest professional research organization. For more information, visit www.costar.com.



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