X0306 4 2021-09-03 0001102934 CMC Materials, Inc. CCMP 0001201094 NOGLOWS WILLIAM P C/O CMC MATERIALS, INC. 870 COMMONS DRIVE AURORA IL 60504 1 Common Stock 2021-09-03 4 I 0 7500 0 D 33625 I Trust Common Stock 2021-09-03 4 I 0 7500 0 A 7500 I Trust Common Stock 2021-09-07 4 I 0 7500 0 D 26125 I Trust Common Stock 2021-09-07 4 I 0 7500 0 A 7500 I Trust Transfer of shares from Mrs. Noglows trust to a trust for the benefit of a child of Mr. and Mrs. Noglows, as to which Mr. Noglows has investment and voting, but no ownership, control. Represents shares that are held in trust for the benefit of a child of Mr. and Mrs. Noglows, as to which Mr. Noglows has investment and voting, but no ownership, control. He is not deemed the beneficial owner of such shares for Section 16 purposes but wishes to continue to report these shares on a voluntary basis. Transfer of shares from Mrs. Noglows trust to a trust for the benefit of a child of Mr. and Mrs. Noglows, as to which Mr. Noglows has investment and voting, but no ownership, control. Represents shares that are held in trust for the benefit of Mr. and Mrs. Noglows' child, as to which Mr. Noglows has investment and voting control, but no ownership, control. He is not deemed the beneficial owner of such shares for Section 16 purposes but wishes to continue to report these shares on a voluntary basis. /s/ H. Carol Bernstein (Power of Attorney) 2021-09-08