X0306 4 2019-01-12 0 0001269021 PORTOLA PHARMACEUTICALS INC PTLA 0001574591 Dier Mardi C/O PORTOLA PHARMACEUTICALS, INC. 270 EAST GRAND AVENUE SOUTH SAN FRANCISCO CA 94080 0 1 0 0 EVP, CFO & CBO Common Stock 2019-01-12 4 A 0 2125 0.00 A 98800 D Common Stock 2019-01-15 4 F 0 868 24.25 D 97932 D Each Performance Stock Unit ("PSU") granted March 29, 2018 represented a contingent right to receive one share of Issuer's Common Stock. 2,125 PSUs vested on January 12, 2019 upon certification by the Issuer's Compensation Committee of the FDA's December 31, 2018 approval of Andexxa Gen 2 in the United States. An additional 2,125 PSUs will vest on the first anniversary of the Certification Date. Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of Performance Stock Units. This sale is 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 does not represent a discretionary trade by the reporting person. The sale is intended to comply with the requirements of Rule 10b5-1(c)(1)(i)(B) under the Exchange Act and be interpreted to meet the requirements of Rule 10b5-1(c). /s/ Mike Ouimette, as attorney-in-fact 2019-01-15