James Alan Schreiner - 16 Sep 2021 Form 4 Insider Report for MKS INSTRUMENTS INC (MKSI)

Role: Sr. VP & COO
Signature: /s/ M. Kathryn Rickards, attorney-in-fact
Issuer symbol: MKSI
Transactions as of: 16 Sep 2021
Net transactions value: -$68,327
Form type: 4
Filing time: 17 Sep 2021, 11:29:23 UTC
Next filing: 24 Jan 2022
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MKSI	Common Stock	Options Exercise		+1,434	+63%		3,727	16 Sep 2021	Direct	F1
transaction	MKSI	Common Stock	Tax liability	$68,327	-454	-12%	$150.50	3,273	16 Sep 2021	Direct	F2

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	MKSI	Restricted Stock Unit	Options Exercise		-1,434	-17%		6,787	16 Sep 2021	Common Stock	1,434		Direct	F1, F3

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
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 vest in three equal annual installments commencing on September 16, 2020, provided that if, in any vesting year, September 16th is not a business day, such vesting shall occur on the next business day.