X0206 3 2018-09-27 0 0001656634 Gritstone Oncology, Inc. GRTS 0001754470 Hawryluk Matthew C/O GRITSTONE ONCOLOGY, INC. 5858 HORTON STREET, SUITE 210 EMERYVILLE CA 94608 0 1 0 0 See Remarks Common Stock 143224 D Stock Option (Right to Buy) 9.60 2018-10-27 2028-08-06 Common Stock 14492 D The stock option vests and becomes exercisable in equal monthly installments over 48 months commencing on September 27, 2018. Executive Vice President and Chief Business Officer /s/ Dana B. Johnson, Attorney-in-Fact for Matthew Hawryluk 2018-09-27