0001057352-08-000093 10-Q 5 20080930 20081106 20081106 COSTAR GROUP INC 0001057352 7389 522091509 1231 10-Q 34 000-24531 081166152 2 BETHESDA METRO CENTER 10TH FLOOR BETHESDA MD 20814 3012158300 2 BETHESDA METRO CENTER 10TH FLOOR BETHESDA MD 20814 10-Q 1 third_quarter2008form10-q.htm 3Q 2008 10-Q EX-31.1 2 exhibit31_1.htm SEC CEO CERT EX-31.2 3 exhibit31_2.htm SEC CFO CERT EX-32.1 4 exhibit32_1.htm SEC CEO 906 CERT EX-32.2 5 exhibit32_2.htm SEC CFO 906 CERT