<SEC-DOCUMENT>0001127602-20-021105.txt : 20200706
<SEC-HEADER>0001127602-20-021105.hdr.sgml : 20200706
<ACCEPTANCE-DATETIME>20200706120327
ACCESSION NUMBER:		0001127602-20-021105
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200702
FILED AS OF DATE:		20200706
DATE AS OF CHANGE:		20200706

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			COLELLA GERARD G
		CENTRAL INDEX KEY:			0001256715

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-23621
		FILM NUMBER:		201012613

	MAIL ADDRESS:	
		STREET 1:		6 SHATTUCK RD
		CITY:			ANDOVER
		STATE:			MA
		ZIP:			01810

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MKS INSTRUMENTS INC
		CENTRAL INDEX KEY:			0001049502
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL [3823]
		IRS NUMBER:				042277512
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2 TECH DRIVE
		STREET 2:		SUITE 201
		CITY:			ANDOVER
		STATE:			MA
		ZIP:			01810
		BUSINESS PHONE:		978-645-5500

	MAIL ADDRESS:	
		STREET 1:		2 TECH DRIVE
		STREET 2:		SUITE 201
		CITY:			ANDOVER
		STATE:			MA
		ZIP:			01810
</SEC-HEADER>
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    <footnotes>
        <footnote id="F1">Each restricted stock unit represents the contingent right to receive one share of common stock of MKS Instruments, Inc.</footnote>
        <footnote id="F2">Shares used to satisfy taxes.  This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the reporting person.</footnote>
        <footnote id="F3">These RSUs were awarded on February 15, 2017 and were subject to the achievement of performance criteria determined in the first year of grant.  These RSUs were scheduled to vest on February 18, 2020.</footnote>
        <footnote id="F4">On January 1, 2020, Mr. Colella retired from the Company and pursuant to the terms of his RSU Agreement, these RSUs fully vested on that date but were not distributable until July 2, 2020 in accordance with Internal Revenue Code Section 409A.</footnote>
        <footnote id="F5">These RSUs were awarded on February 15, 2017.  These RSUs were scheduled to vest on February 18, 2020.</footnote>
        <footnote id="F6">These RSUs were awarded on February 15, 2018 and were subject to the achievement of performance criteria determined in the first year of grant.  These RSUs were scheduled to vest on February 18, 2020.</footnote>
        <footnote id="F7">These RSUs were awarded on February 15, 2018 and were subject to the achievement of performance criteria determined in the first year of grant.  These RSUs were scheduled to vest on February 16, 2021.</footnote>
        <footnote id="F8">These RSUs were awarded on February 15, 2018.  These RSUs were scheduled to vest on February 18, 2020.</footnote>
        <footnote id="F9">These RSUs were awarded on February 15, 2018.  These RSUs were scheduled to vest on February 16, 2021.</footnote>
        <footnote id="F10">These RSUs were awarded on February 15, 2019 and were subject to the achievement of performance criteria determined in the first year of grant.  These RSUs were scheduled to vest on February 16, 2021.</footnote>
        <footnote id="F11">These RSUs were awarded on February 15, 2019 and were subject to the achievement of performance criteria determined in the first year of grant.  These RSUs were scheduled to vest on February 15, 2022.</footnote>
        <footnote id="F12">These RSUs were awarded on February 15, 2019.  These RSUs were scheduled to vest on February 18, 2020.</footnote>
        <footnote id="F13">These RSUs were awarded on February 15, 2019.  These RSUs were scheduled to vest on February 16, 2021.</footnote>
        <footnote id="F14">These RSUs were awarded on February 15, 2019.  These RSUs were scheduled to vest on February 15, 2022.</footnote>
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