0001057352-07-000002 8-K 1 20070108 8.01 20070108 20070108 COSTAR GROUP INC 0001057352 7389 522091509 1231 8-K 34 000-24531 07518057 2 BETHESDA METRO CENTER 10TH FLOOR BETHESDA MD 20814 3012158300 2 BETHESDA METRO CENTER 10TH FLOOR BETHESDA MD 20814 8-K 1 form8-k.htm OTHER EVENTS, ITEM 8.01