X0306 4 2017-12-11 0001102934 CABOT MICROELECTRONICS CORP CCMP 0001559386 Polezoes Lisa A C/O CABOT MICROELECTRONICS CORPORATION 870 COMMONS DRIVE AURORA IL 60504 1 VP, Human Resources Common Stock 2017-12-11 4 A 0 1083 92.31 A 21425.843 D Common Stock 2017-12-11 4 A 0 541 92.31 A 21966.843 D Represents restricted shares purchased under the Issuer's Omnibus Incentive Plan pursuant to the Issuer's Deposit Share Program: 1083 of such shares are Deposit Shares under the Program purchased at full value by the Participant that vested on 12/11/2017, and 541 shares of such are Award Shares under the Program awarded to the Participant that will vest on 12/11/2020, subject to the satisfaction of certain conditions. /s/ H. Carol Bernstein (Power of Attorney) 2017-12-13