| Date | Event |
| 9-Nov-09 | Ex-Date for dividend payment of $0.01 |
| 6-Nov-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 10-Q, Quarterly Report |
| 29-Oct-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Other Events, Financial Statements and Exhibits |
| 31-Aug-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K/A, Results of Operations and Financial Condition, Financial Statements |
| 12-Aug-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Regulation FD Disclosure, Financial Statements and Exhibits |
| 6-Aug-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Entry into a Material Definitive Agreement, Regulation FD Disclosure, |
| 5-Aug-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Other Events |
| 3-Aug-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Other Events, Financial Statements and Exhibits |
| 3-Aug-09 | Ex-Date for dividend payment of $0.01 |
| 31-Jul-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 10-Q, Quarterly Report |
| 23-Jul-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Other Events, Financial Statements and Exhibits |
| 29-Jun-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Other Events, Amendments to Articles of Inc. or Bylaws; Change in Fis |
| 15-Jun-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Results of Operations and Financial Condition, Financial Statements a |
| 2-Jun-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Change in Directors or Principal Officers, Financial Statements and E |
| 6-May-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 10-Q, Quarterly Report |
| 23-Apr-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Other Events, Financial Statements and Exhibits |
| 12-Mar-09 | Price hit new 52-week low ($4.76) |
| 6-Mar-09 | Price hit new 52-week low ($5.18) |
| 5-Mar-09 | Price hit new 52-week low ($5.60) |
| 27-Feb-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 10-K, Annual Report |
| 19-Feb-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Change in Directors or Principal Officers, Financial Statements and E |
| 30-Jan-09 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Results of Operations and Financial Condition, Other Events |
| 21-Nov-08 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Entry into a Material Definitive Agreement, Unregistered Sale of Equi |
| 7-Nov-08 | COLUMBIA BANKING SYSTEM INC Files SEC form 10-Q, Quarterly Report |
| 5-Nov-08 | COLUMBIA BANKING SYSTEM INC Files SEC form 8-K, Other Events, Financial Statements and Exhibits |