MKS INC — Director's Dealing 2018

May 10, 2018

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2018-05-09

Reporting Person: BERTUCCI JOHN R (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2018-05-09	Common Stock	A	1499.118	—	Acquired	198745.118	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	51000	Indirect
Common Stock	27782	Indirect
Common Stock	186505	Indirect

Footnotes

F1: These restricted stock units become fully vested on the day prior to the first annual meeting of shareholders following the date of grant (or if no such meeting is held within 13 months after the date of grant, on the 13 month anniversary of the date of grant).

F2: Each restricted stock unit represents the contingent right to receive one share of common stock of MKS Instruments, Inc.

F3: Adjusted to reflect cash payment in lieu of distribution of a fractional share.