X0306 4 2016-03-02 0 0001269021 PORTOLA PHARMACEUTICALS INC PTLA 0001574589 Curnutte John T C/O PORTOLA PHARMACEUTICALS, INC. 270 EAST GRAND AVE. SOUTH SAN FRANCISCO CA 94080 0 1 0 0 Executive Vice President Common Stock 2016-03-02 4 F 0 1271 31.75 D 8729 D Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of the Restricted Stock Units granted on January 27, 2015. 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 2016-03-03