X0306 4 2017-04-03 0 0001631650 Aimmune Therapeutics, Inc. AIMT 0001648889 DeSouza Warren L. AIMMUNE THERAPEUTICS, INC. 8000 MARINA BOULEVARD, SUITE 300 BRISBANE CA 94005-1884 0 1 0 0 Chief Financial Officer Common Stock, $0.0001 par value 2017-04-03 4 M 0 15000 3.022 A 35681 D Common Stock, $0.0001 par value 2017-04-03 4 S 0 15000 21.5824 D 20681 D Stock Option (right to buy) 3.022 2017-04-03 4 M 0 15000 0.00 D 2025-05-13 Common Stock 15000 303794 D The sale reported in the Form 4 was effected pursuant to a Rule 10b5 1 trading plan adopted by the Reporting Person. The transaction was executed in multiple trades in prices ranging from $21.30 to $21.79, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a stockholder of the Issuer, information regarding the number of shares and prices at which the transaction was effected. The option is immediately exercisable in full or in part. The shares vest pursuant to the following schedule: Twenty Five Percent (25%) of the shares subject to the option vest on the first anniversary measured from April 16, 2015 (the "Vesting Commencement Date") and the remaining shares subject to the option vest in 36 successive, equal monthly installments thereafter on each monthly anniversary of the Vesting Commencement Date, subject to Reporting Person's continued service relationship with the Issuer on each such vesting date. /s/ Douglas T. Sheehy, as Attorney-in-Fact for Warren L. DeSouza 2017-04-05