X0306 4 2020-07-02 1 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 and CFO Common Stock 2020-07-02 4 D 0 39563 18.00 D 0 D Common Stock 2020-06-18 4 A 0 10 8.36 A 10 D Common Stock 2020-07-02 4 D 0 10 18.00 D 0 D Performance Stock Units 2020-07-02 4 D 0 48750 0.00 D Common Stock 48750 0 D Performance Stock Units 2020-07-02 4 D 0 24375 D Common Stock 24375 0 D Stock Option (Right to Buy) 12.79 2020-07-02 4 D 0 65000 5.21 D 2030-01-30 Common Stock 65000 0 D Stock Option (Right to Buy) 12.79 2020-07-02 4 D 0 32500 D 2030-01-30 Common Stock 32500 0 D Stock Option (Right to Buy) 2020-07-02 4 D 0 371545 D Common Stock 371545 0 D Restricted Stock Units 2020-07-02 4 D 0 32291 0.00 D Common Stock 32291 0 D Pursuant to the Agreement and Plan of Merger, dated as of May 5, 2020, by and among Portola Pharmaceuticals, Inc. (the "Issuer"), Alexion Pharmaceuticals, Inc. ("Alexion") and Odyssey Merger Sub Inc. ("Merger Sub") (the "Merger Agreement"), on July 2, 2020, Merger Sub merged with and into the Issuer, with the Issuer continuing as the surviving corporation and a direct, wholly owned subsidiary of Alexion (the "Merger"). At the effective time of the Merger (the "Effective Time"), these shares were canceled in exchange for $18.00 per share in cash, without interest and subject to any applicable withholding taxes. The acquisition of 10 shares by the Reporting Person on June 18, 2020 pursuant to the Issuer's Employee Stock Purchase Plan. Immediately prior to the Effective Time, each performance restricted stock unit ( "Issuer PSU") was converted into a restricted stock unit with respect to the number of shares of Alexion common stock determined by multiplying (i) the total number of shares subject to such Issuer PSU by (ii) an exchange ratio equal to $18.00 divided by $112.39 (the "Exchange Ratio"). In connection with the Merger, these performance restricted stock units were canceled without payment immediately prior to the Effective Time. At the Effective Time, each of these unvested and outstanding options was accelerated, canceled and converted into the right to receive a cash amount equal to the product of (i) the number of shares that are subject to such options and (ii) $18.00 less the applicable exercise price per share of such options, subject to any applicable withholding or other taxes required by applicable law. At the Effective Time, each of these unvested and outstanding options became fully vested (assuming performance at target), canceled and converted into the right to receive a cash amount equal to the product of (i) the number of shares that were subject to such options and (ii) $18.00 less the applicable exercise price per share of such options, subject to any applicable withholding or other taxes required by applicable law. In connection with the Merger, these options were accelerated and canceled without payment. At the Effective Time, each restricted stock unit ("Issuer RSU") was converted into a restricted stock unit, subject to substantially the same terms and conditions as were applicable to such Issuer RSU, with respect to the number of shares of Alexion common stock determined by multiplying (i) the total number of shares subject to such Issuer RSU by (ii) the Exchange Ratio. /s/ Mike Ouimette, Attorney-in-fact 2020-07-02