X0607 3 2026-06-01 0 0001049502 MKS INC MKSI 0002135522 Donlan Renee Martel false C/O MKS INC. 2 TECH DRIVE ANDOVER MA 01810 1 EVP, GC & CCO Common Stock 9471.7084 D Restricted Stock Unit Common Stock 415.813 D Restricted Stock Unit Common Stock 2481.346 D Restricted Stock Unit Common Stock 929.368 D These restricted stock units (RSUs) vest on April 15, 2027. Each RSU represents the contingent right to receive one share of common stock of MKS Inc. These RSUs vest in two equal annual installments commencing on April 15, 2027, provided that if, in any vesting year, April 15th is not a business day, such vesting shall occur on the next business day. These RSUs vest in three equal annual installments commencing on April 15, 2027, provided that if, in any vesting year, April 15th is not a business day, such vesting shall occur on the next business day. Exhibit 24 - Power of Attorney /s/ M. Kathryn Rickards, attorney-in-fact 2026-06-04