X0306 4 2019-01-17 0 0001576263 Mirati Therapeutics, Inc. MRTX 0001465837 Boxer Capital, LLC 11682 EL CAMINO REAL, SUITE 320 SAN DIEGO CA 92130 0 0 1 0 Common Stock 2019-01-17 4 P 0 150000 62.00 A 1715560 D These securities are owned directly by Boxer Capital, LLC ("Boxer Capital"), which may be deemed to be a member of a "group" for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended, consisting of (i) Braslyn Ltd. ("Braslyn"), (ii) Boxer Capital, (iii) Boxer Asset Management Inc. ("Boxer Management"), (iv) MVA Investors, LLC ("MVA Investors"), (v) Tuesday Thirteen Inc., (vi) Joe Lewis, (vii) Rodney W. Lappe, (viii) Ivan M. Lieberburg, (ix) Aaron I. Davis, (x) Neil Reisman, (xi) Shehan B. Dissanayake, and (xii) Christopher Fuglesang (collectively, the "Boxer Group), and indirectly by Boxer Management and Messrs. Lewis, Fuglesang, Reisman, Lieberburg, Dissanayake and Davis, by virtue of their ownership in Boxer Capital. (Continued from Footnote 1) Each of Messrs. Fuglesang, Reisman, Lieberburg, Dissanayake and Davis is a member of Boxer Capital. Each member of the Boxer Group other than Boxer Capital disclaims beneficial ownership of these securities to the extent it or he does not have a pecuniary interest therein. Boxer Capital, LLC, By: /s/ Aaron Davis 2019-01-22