X0306 4 2015-03-04 0 0000073020 NORTHWEST NATURAL GAS CO NWN 0001571275 WILSON BRODY J 220 NW SECOND AVENUE PORTLAND OR 97209 0 1 0 0 Controller Common Stock 2015-03-04 4 F 0 214 46.57 D 907 D Common Stock 119.3098 I See Footnote Shares were withheld by the issuer to cover withholding taxes on issuance of shares due to vesting of restricted stock units. Organization and Executive Compensation Committee certification of satisfaction of the performance threshold and vesting for these restricted stock units was reported on Form 4 filed on February 27, 2015. Includes 183 restricted stock units granted under issuer's Long-Term Incentive Plan, which will fully vest on March 1, 2016. Shares held in the reporting person's account under issuer's Retirement K Savings Plan as of February 28, 2015. Shawn M. Filippi, Attorney-in-Fact 2015-03-06