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    <ACCEPTANCE-DATETIME>20190109080049
    ACCESSION NUMBER:		0001193125-19-004961
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		53
    CONFORMED PERIOD OF REPORT:	20190109
    ITEM INFORMATION:		Results of Operations and Financial Condition
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20190109
    DATE AS OF CHANGE:		20190109

    FILER:

    	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

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-23621
    		FILM NUMBER:		19517341

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

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    		STREET 2:		SUITE 201
    		CITY:			ANDOVER
    		STATE:			MA
    		ZIP:			01810
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