PRESS RELEASE DETAIL


May 09, 2011

CoStar Group Recognizes Top Dealmakers in Commercial Real Estate With CoStar Power Broker AwardsEach year,

Backed by CoStar's Research, Annual Industry-wide Awards Presented to the Best of the Best in Commercial Real Estate Brokerage WASHINGTON, May 9, 2011 -- CoStar Group, Inc. (Nasdaq:CSGP), commercial real estate's leading provider of information and analytic services, is pleased to announce the winners of the 2010 CoStar Power Broker Awards™, recognizing the best of the best in commercial real estate brokerage.

Backed by CoStar's Research, Annual Industry-wide Awards Presented to the Best of the Best in Commercial Real Estate Brokerage WASHINGTON, May 9, 2011 -- CoStar Group, Inc. (Nasdaq:CSGP), commercial real estate's leading provider of information and analytic services, is pleased to announce the winners of the 2010 CoStar Power Broker Awards™, recognizing the best of the best in commercial real estate brokerage.

Each year, CoStar tallies the commercial real estate sales and lease transactions that closed during the previous year and presents CoStar Power Broker Awards to the firms and individual brokers who closed the highest transaction volume in commercial property sales and leases in their respective market. As the largest professional research organization serving the commercial real estate industry, CoStar is uniquely positioned to identify the top firms and brokers in each market throughout the U.S.

"CoStar Group is very proud to recognize the select few commercial real estate brokerage firms and brokers who performed at the industry's highest level and achieved remarkable sales and leasing success in 2010," said CoStar Group Founder and CEO Andrew C. Florance. "These top performers truly represent the best of the best in commercial real estate, and they deserve to be recognized for their proven deal-making abilities. We congratulate all the award winners on their impressive professional accomplishments."

The CoStar Power Broker Awards span the country, recognizing winners from Birmingham and Jacksonville to Sacramento and San Jose, from Phoenix and Orange County to Milwaukee and Minneapolis, and from San Jose and Denver to Nashville and Cincinnati. Winners include brokers from such major firms as CB Richard Ellis, Cassidy Turley Commercial Real Estate, Colliers International, Cushman & Wakefield, Eastdil Secured, Henricks & Partners, HFF, Grubb & Ellis, Jones Lang LaSalle, Marcus & Millichap, NAI Global, Studley, Transwestern and hundreds of other firms.

The complete list of CoStar Power Broker Award winners listed by market can be found at http://www.costar.com/PowerBrokers/.

Now in their ninth year, the CoStar Power Broker Awards recognize the top firms and individual dealmakers by market based on overall transaction volume during the previous year. All awards are based on transaction data in CoStar's commercial real estate database, the largest, independently researched database of commercial real estate property information available online. Information in CoStar's database is verified and continuously updated by approximately 900 CoStar researchers, comprising the largest commercial real estate research operation of its kind. CoStar's U.S. database contains more than 3.3 million commercial properties, and the total U.S. square footage of gross building area tracked and maintained by CoStar exceeds 76 billion square feet.

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.



'