X0306 4 2018-06-12 0 0001491576 TESARO, Inc. TSRO 0001553053 Alleva Lawrence M C/O TESARO, INC. 1000 WINTER STREET WALTHAM MA 02451 1 0 0 0 Common Stock 2018-06-12 4 M 0 7142 6.615 A 37044 D Common Stock 2018-06-12 4 S 0 2942 42.62 D 34102 D Common Stock 2018-06-12 4 S 0 4200 43.46 D 29902 D Director Nonqualified Stock Option (right to buy) 6.615 2018-06-12 4 M 0 7142 0 D 2022-05-02 Common Stock 7142 0 D The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person. The price reported is a weighted average. The shares were sold in multiple transactions at prices ranging from $42.18 to $42.97, inclusive. The reporting person undertakes to provide to TESARO, Inc., any security holder of TESARO, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein. The price reported is a weighted average. The shares were sold in multiple transactions at prices ranging from $43.19 to $43.88, inclusive. The reporting person undertakes to provide to TESARO, Inc., any security holder of TESARO, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth herein. Of the original grant of options to purchase 7,142 shares of common stock, 2,380 vested on April 27, 2013, 2,381 vested on April 27, 2014, and 2,381 vested on April 27, 2015. /s/ Joseph L. Farmer, Attorney-in-Fact 2018-06-14