X0306 4 2017-11-01 0 0001084717 PACIFIC CONTINENTAL CORP PCBK 0001686163 Woods Duane C. 111 W. 7TH AVE. EUGENE OR 97401 1 0 0 0 COMMON STOCK 2017-11-01 4 D 0 4363 D 0 D In connection with the merger of Pacific Continental Corporation ("Pacific Continental") with and into Columbia Banking system, Inc. ("Columbia") on November 1, 2017 (the "Merger"), pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated January 9, 2017, by and among Columbia, Pacific Continental and Coast Merger Sub, Inc., each outstanding Pacific Continental common share was converted into the right to receive 0.6430 of a Columbia common share. Duane Woods 2017-11-01