| Date | Event |
| 20-Nov-09 | COSTAR GROUP INC Files SEC form 8-K, Entry into a Material Definitive Agreement, Creation of a Direct Financial Oblig |
| 4-Nov-09 | COSTAR GROUP INC Files SEC form 10-Q, Quarterly Report |
| 22-Oct-09 | COSTAR GROUP INC Files SEC form 8-K, Results of Operations and Financial Condition, Financial Statements and Exhibits |
| 20-Oct-09 | COSTAR GROUP INC Files SEC form 8-K, Other Events |
| 17-Sep-09 | Price hit new 52-week high ($41.42) |
| 31-Aug-09 | COSTAR GROUP INC Files SEC form 8-K, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance |
| 31-Jul-09 | COSTAR GROUP INC Files SEC form 10-Q, Quarterly Report |
| 22-Jul-09 | COSTAR GROUP INC Files SEC form 8-K, Results of Operations and Financial Condition, Unregistered Sale of Equity Secur |
| 1-Jul-09 | Price hit new 52-week high ($40.98) |
| 5-Jun-09 | Price hit new 52-week high ($39.79) |
| 8-May-09 | COSTAR GROUP INC Files SEC form 10-Q, Quarterly Report |
| 23-Apr-09 | COSTAR GROUP INC Files SEC form 8-K, Results of Operations and Financial Condition, Financial Statements and Exhibits |
| 9-Mar-09 | Price hit new 52-week low ($24.11) |
| 6-Mar-09 | Price hit new 52-week low ($24.54) |
| 3-Mar-09 | Price hit new 52-week low ($24.71) |
| 24-Feb-09 | COSTAR GROUP INC Files SEC form 10-K, Annual Report |
| 20-Feb-09 | COSTAR GROUP INC Files SEC form 8-K, Other Events |
| 19-Feb-09 | COSTAR GROUP INC Files SEC form 8-K, Results of Operations and Financial Condition, Financial Statements and Exhibits |
| 22-Jan-09 | COSTAR GROUP INC Files SEC form 8-K, Amendments to Articles of Inc. or Bylaws; Change in Fiscal Year, Financial State |
| 6-Nov-08 | COSTAR GROUP INC Files SEC form 10-Q, Quarterly Report |
| 30-Oct-08 | COSTAR GROUP INC Files SEC form 8-K, Results of Operations and Financial Condition, Financial Statements and Exhibits |