PRESS RELEASE DETAIL


Dec 18, 2007

CoStar Group Sets New Industry Record for Commercial Property Listings

2006-04-13 2006 CoStar Group Sets New Industry Record for Commercial Property Listings More than a Half Million Commercial Listings and 35 Billion Square Feet of Inven...

2006-04-13 2006 CoStar Group Sets New Industry Record for Commercial Property Listings More than a Half Million Commercial Listings and 35 Billion Square Feet of Inventory in Industry's Most Comprehensive Database

BETHESDA, MD — CoStar Group, Inc. (NASDAQ: CSGP), the leading provider of information services to commercial real estate professionals, today announced that it set a new industry record by surpassing the half-million mark for researched commercial for-sale and for-lease listings in its online database. CoStar has more than 540,000 commercial property listings available — a claim no other commercial real estate information provider can make.

"CoStar offers more commercial real estate listings on the Internet than anyone," said Andrew C. Florance, president and CEO of CoStar Group. "No other industry provider can match our quality, breadth and depth of information. We also have the most powerful software tools on the market to help customers make better and faster decisions when it comes to buying, selling or leasing commercial properties."

As the industry's largest commercial real estate research organization, CoStar gathers and verifies for-sale and for-lease listings across all property types — office, industrial, retail, land, mixed-use, hospitality and multifamily — throughout the United States and United Kingdom.

In March alone, CoStar added more than 80,000 new listings to its online database. This represents a 281 percent increase over the monthly average of listings added by CoStar during the previous three months.

According to Florance, a combination of factors helped fuel this surge in listings. First, a cooling national housing market is prompting more residential real estate agents to explore offering some level of service in the commercial marketplace. Another reason is greater visibility among commercial brokers of CoStar's web-based subscription product for accessing for-sale listings called CoStar Commercial MLS™.

In addition to providing commercial real estate professionals with the most deal-ready listings, CoStar's database contains detailed information on 1.8 million properties and more than 35 billion square feet of rentable building area.

The company's team of over 800 researchers also personally contacts property brokers, owners, developers, lenders, tenants and appraisers to help ensure the completeness and accuracy of CoStar's listings — a level of due diligence that no other commercial real estate information service provides.

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 66 U.S. markets 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 risks and uncertainties that could cause actual results to differ materially from these 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-K for the year ended December 31, 2005, under the heading "Risk Factors." In addition to these statements, there can be no assurance that CoStar's services will help customers make better and faster decisions when it comes to buying, selling or leasing commercial properties, or that CoStar's research methods ensure the completeness and accuracy of CoStar's listings. 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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