X0306 4 2019-02-06 0 0001377121 Protagonist Therapeutics, Inc PTGX 0001120477 PATEL DINESH V PH D C/O PROTAGONIST THERAPEUTICS, INC. 7707 GATEWAY BLVD., SUITE 140 NEWARK CA 94560 1 1 0 0 President and CEO Common Stock 2019-02-06 4 S 0 777 8.0981 D 367396 D Common Stock 2019-02-06 4 S 0 10132 7.71 D 357264 D The sales reported on this Form 4 represent shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person. /s/ Niall Murphy, Attorney-in-Fact for Dinesh V. Patel, Ph.D. 2019-02-08