MKS INC — Director's Dealing 2016

Feb 29, 2016

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2016-02-25

Reporting Person: Lee John Tseng-Chung (Sr. VP, Business Units)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2016-02-25	Common Stock	M	2862.81	—	Acquired	10119.097	Direct
2016-02-25	Common Stock	M	2105.007	—	Acquired	12224.104	Direct
2016-02-25	Common Stock	F	1613	$32.77	Disposed	10611.104	Direct
2016-02-26	Common Stock	S	994	$32.70	Disposed	9617.104	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2016-02-25	Restricted Stock Unit	$	M	2862.81	Disposed		Common Stock (2862.81)	Direct
2016-02-25	Restricted Stock Unit	$	M	2105.007	Disposed		Common Stock (2105.007)	Direct

Footnotes

F1: Each restricted stock unit represents the contingent right to receive one share of common stock of MKS Instruments, Inc.

F2: This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the reporting person.

F3: These RSUs are subject to the achievement of performance criteria determined in the first year of grant and thereafter vest in three equal annual installments commencing on the first anniversary of the grant date.

F4: These RSUs vest in three equal annual installments commencing on the first anniversary of the grant date.