X0306 4 2020-02-21 0 0001676725 IDEAYA Biosciences, Inc. IDYA 0001777415 Dillon Michael P. C/O IDEAYA BIOSCIENCES, INC. 7000 SHORELINE COURT, SUITE 350 SOUTH SAN FRANCISCO CA 94080 0 1 0 0 SVP, Chief Scientific Officer Stock Option (right to buy) 6.92 2020-02-21 4 A 0 62500 0.00 A 2030-02-20 Common Stock 62500 62500 D 25% of the shares subject to the option vest on the first anniversary measured from January 1, 2020 (the "Vesting Commencement Date"), and 1/48th of the total number of shares vest monthly thereafter, such that 100% of the shares subject to the option will be fully vested and exercisable on the fourth anniversary of the Vesting Commencement Date. /s/ Jason Throne, as Attorney-in-Fact for Michael P. Dillon 2020-02-25