X0306 4 2015-12-09 0 0000073020 NORTHWEST NATURAL GAS CO NWN 0001192777 DOOLITTLE LEA ANNE 220 NW SECOND AVENUE PORTLAND OR 97209 0 1 0 0 Chief Adm. Officer & SVP Common Stock 2015-12-09 4 S 0 350 49.0958 D 5033.8251 D Common Stock 8182.1041 I See Footnote Common Stock 1825.224 I See Footnote Common Stock 519.468 I See Footnote Common Stock 295.6875 I See Footnote Common Stock 316.6158 I See Footnote This transaction was executed in multiple trades on reported date with prices ranging from $49.0901 to $49.10, resulting in an average price of $49.0958. Northwest Natural Gas Company will provide upon request by the Commission staff or a security holder of the issuer full information regarding the number of shares purchased or sold at each separate price. Shares are held in reporting person's account under issuer's Retirement K Savings Plan as of November 30, 2015. Reflects shares that have been credited to reporting person's account under the issuer's Deferred Compensation Plan for Directors and Executives. Reflects shares that have been credited to reporting person's account under the issuer's Executive Deferred Compensation Plan. Shares are held in account of reporting person's spouse. Shares are held in reporting person's spouse's account under issuer's Retirement K Savings Plan as of November 30, 2015. Shawn M. Filippi, Attorney-in-Fact 2015-12-10