X0306 4 2016-03-02 0 0000073020 NORTHWEST NATURAL GAS CO NWN 0001668229 Murandu Ngoni 220 NW SECOND AVENUE PORTLAND OR 97209 0 1 0 0 VP & CIO Common Stock 2016-03-02 4 F 0 94 49.44 D 1002 D Common Stock 34.4442 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 the satisfaction of the performance threshold occurred on February 24, 2016 before the reporting person became an executive officer. Includes 660 restricted stock units (RSUs) granted under issuer's Long Term Incentive Plan. The RSUs vest in two equal installments on each March 31, 2016 and 2017. Shares held in reporting person's account under the issuer's Retirement K Savings Plan as of February 29, 2016. Shawn M. Filippi, Attorney-in-Fact 2016-03-02