X0306 4 2018-03-16 0 0001557746 Aclaris Therapeutics, Inc. ACRS 0001654343 Tullman Stephen A. C/O ACLARIS THERAPEUTICS, INC. 640 LEE ROAD, SUITE 200 WAYNE PA 19087 1 0 0 0 Common Stock 2018-03-16 4 J 0 94151 0.00 D 0 I By NST, LLC Common Stock 2018-03-16 4 J 0 9018 0.00 A 130807 D Common Stock 394014 I By Trust Pro rata distribution by NST, LLC, of which the reporting person is a member and the sole Manager, in accordance with NST, LLC's Limited Liability Company Operating Agreement. These shares were held by NST, LLC of which the reporting person is a member and the sole Manager. The reporting person had sole voting and dispositive power over the shares held by NST, LLC. These shares are held by the 2007 Irrevocable Trust of Stephen A. Tullman, for which the reporting person's spouse serves as the trustee. /s/ Brian F. Leaf, Attorney-in-fact 2018-03-20