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    ACCESSION NUMBER:		0001193125-19-281646
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		34
    CONFORMED PERIOD OF REPORT:	20191028
    ITEM INFORMATION:		Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers
    ITEM INFORMATION:		Amendments to the Registrant's Code of Ethics, or Waiver of a Provision of the Code of Ethics
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20191101
    DATE AS OF CHANGE:		20191101

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    	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

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    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-23621
    		FILM NUMBER:		191186125

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

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    		STATE:			MA
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