X0306 4 2020-06-16 0 0001478121 Pfenex Inc. PFNX 0001612843 Lucy Patrick K. C/O PFENEX INC., 10790 ROSELLE STREET SAN DIEGO CA 92121 0 1 0 0 Chief Business Officer Common Stock 2020-06-16 4 M 0 770 3.38 A 91016 D Common Stock 2020-06-16 4 S 0 770 10.2251 D 90246 D Stock Option (right to buy) 3.38 2020-06-16 4 M 0 770 0.00 D 2028-02-01 Common Stock 770 60486 D The sale of shares reported on this Form 4 was effected pursuant to a Rule 10b5-1 trading plan entered into by the reporting person on November 20, 2019. Represents the weighted average share price of an aggregate total of 770 shares sold in the price range of $10.03 to $10.35 by the reporting person. The reporting person undertakes to provide upon request by the Commission staff, the issuer or a security holder of the issuer, full information regarding the number of shares sold at each separate price. Twenty five percent (25%) of the shares subject to the option shall vest and become exercisable on the one year anniversary of the Vesting Commencement Date and one forty-eighth (1/48th) of the total number of shares subject to the Option shall vest every month thereafter such that all shares shall be fully vested on the four (4) year anniversary of the Vesting Commencement Date, subject to the reporting person continuing to be a Service Provider (as such term is defined in the Issuer's 2014 Equity Incentive Plan) through each such date. "Vesting Commencement Date" shall mean February 1, 2018. /s/ Marilyn Bock, as Attorney-in-Fact 2020-06-17