X0306 4 2019-05-23 0 0001631650 Aimmune Therapeutics, Inc. AIMT 0001253886 ENRIGHT PATRICK G C/O LONGITUDE CAPITAL PARTNERS II, LLC 2740 SAND HILL ROAD, SECOND FLOOR MENLO PARK CA 94025 1 0 0 0 Common Stock, $0.0001 par value 2019-05-23 4 A 0 6442 0.00 A 33061 D Common Stock, $0.0001 par value 6013134 I By: LVP2 Stock Option (right to buy) 19.90 2019-05-23 4 A 0 11432 0.00 A 2029-05-23 Common Stock 11432 11432 D These shares represent restricted stock units ("RSUs") and will be settled in common stock upon vesting. The RSUs vest on the earlier of (i) the first anniversary of the grant date or (ii) the date of the 2020 Annual Meeting of the Issuer's stockholders, assuming continuous service as a director until such vesting date. Reflects shares held by Longitude Venture Partners II, L.P. ("LVP2"). Longitude Capital Partners II, LLC ("LCP2") is the general partner of LVP2 and may be deemed to share voting and investment power over the shares of the Issuer held by LVP2. Patrick G. Enright is a managing member of LCP2 and in his capacity as such may be deemed to share voting and investment power over the shares held by LVP2. Mr. Enright disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein. The shares subject to the option will vest and become exercisable as to 100% of the total number of shares subject to the option on the earlier of (i) the first anniversary of the grant date or (ii) the date of the 2020 Annual Meeting of the Issuer's stockholders, assuming continuous service as a director until such vesting date. /s/ Douglas T. Sheehy, as Attorney-in-Fact for Patrick G. Enright 2019-05-28