X0306 4 2021-03-10 0001102934 CMC Materials, Inc. CCMP 0001189831 ECKSTEIN BERNSTEIN H CAROL C/O CABOT MICROELECTRONICS CORPORATION 870 COMMONS DRIVE AURORA IL 60504 1 VP, Sec & General Counsel Common Stock 2021-03-10 4 M 0 3950 60.27 A 47304.024 D Common Stock 2021-03-10 4 S 0 3950 166.1875 D 43354.024 D Stock Options (Right to Buy) 60.27 2021-03-10 4 M 0 3950 0 D 2017-12-05 2026-12-05 Common Stock 3950 0 D 2016 (FY17) Restricted Stock Unit Award Vesting Schedule: 25% 12/05/2017, 25% 12/05/2018, 25% 12/05/2019, 25% 12/05/2020. 2016 (FY17) Non-Qualified Stock Option Grant Vesting Schedule: 25% 12/05/2017, 25% 12/05/2018, 25% 12/05/2019, 25% 12/05/2020. /s/ H. Carol Bernstein (Power of Attorney) 2021-03-10