X0306 4 2018-05-16 0 0001097149 ALIGN TECHNOLOGY INC ALGN 0001188901 SANTORA GREG J C/O ALIGN TECHNOLOGY, INC. 2560 ORCHARD PARKWAY SAN JOSE CA 95131 1 0 0 0 Common Stock 2018-05-16 4 M 0 3115 0 A 22115 I By Trust Restricted Stock Unit 0.0001 2018-05-16 4 M 0 3115 0 D Common Stock 3115 0 D Restricted Stock Unit 0.0001 2018-05-16 4 A 0 1042 0 A Common Stock 1042 1042 D The shares are held directly by a family trust for which the reporting person is a co-trustee. Represents par value of ALGN common stock. 100% of the restricted stock unit granted on May 17, 2017 became vested on May 16, 2018 and shares were delivered to reporting person on that date. 100% of the restricted stock unit granted on May 16, 2018 will become vested on the earlier of (i) May 16, 2019 or (ii) the date of the 2019 annual meeting of stockholders. Shares will be delivered to reporting person on the vest date. Roger E. George Atty-in-Fact for Greg J. Santora 2018-05-18