X0306 4 2018-06-11 0 0001631650 Aimmune Therapeutics, Inc. AIMT 0001389147 DILLY STEPHEN GEORGE AIMMUNE THERAPEUTICS, INC. 8000 MARINA BOULEVARD, SUITE 300 BRISBANE CA 94005-1884 1 1 0 0 President and CEO Common Stock, $0.0001 par value 2018-06-11 4 M 0 29457 3.0221 A 344765 D Common Stock, $0.0001 par value 2018-06-11 4 S 0 29457 30.8348 D 315308 D Common Stock, $0.0001 par value 12009 I By GRAT 2 Common Stock, $0.0001 par value 12009 I By Wife's GRAT 2 Common Stock, $0.0001 par value 25532 I By Family Trust Common Stock, $0.0001 par value 41075 I By Child's Trust 1 Common Stock, $0.0001 par value 41075 I By Child's Trust 2 Stock Option (right to buy) 3.0221 2018-06-11 4 M 0 29457 0.00 D 2025-05-18 Common Stock 29457 295942 D This sale reported in the Form 4 was effected pursuant to a Rule 10b5-1 trading plan adopted by Reporting Person. The transaction was executed in multiple trades in prices ranging from $30.51 to $31.18, 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. These shares are held by Stephen G. Dilly, Trustee, The Stephen G. Dilly 2016 Grantor Retained Annuity Trust DTD August 12, 2016 (the "Second Dilly Trust"). Dr. Dilly has sole voting, investment and dispositive power over the shares held by the Second Dilly Trust. These shares are held by Edwina Lynette Mullens, Trustee, The Edwina Lynette Mullens 2016 Grantor Retained Annuity Trust DTD August 12, 2016 (the "Second Mullens Trust"). Ms. Mullens has sole voting, investment and dispositive power over the shares held by the Second Mullens Trust. Dr. Dilly disclaims beneficial ownership of the shares held by the Second Mullens Trust. These shares are held by Stephen G. Dilly and Edwina Lynette Mullens as Trustees of The Dilly Family Trust dated October 9, 2002 (the "Family Trust"). Dr. Dilly and Ms. Mullens have joint voting, investment and dispositive power over the shares held by the Family Trust. These shares are held by Stephen G. Dilly and Edwina Lynette Mullens as Trustees of The Frederick S W Dilly 2015 Irrevocable Trust dated June 23, 2015 (the "Frederick S W Dilly Trust"). Dr. Dilly and Ms. Mullens have joint voting, investment and dispositive power over the shares held by the Frederick S W Dilly Trust. These shares are held by Edwina Lynette Mullens and Stephen G. Dilly as Trustees of The Harriet F.L. Dilly 2015 Revocable Trust dated June 23, 2015 (the "Harriet F.L. Dilly Trust"). Dr. Dilly and Ms. Mullens have joint voting, investment and dispositive power over the shares held by the Harriet F.L. Dilly Trust. The option is immediately exercisable in full or in part. The shares vest pursuant to the following schedule: One forty-eighth (1/48th) of the shares subject to the option vest in 48 successive, equal monthly installments measured from May 13, 2015, 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 Stephen G. Dilly 2018-06-13