    <SEC-DOCUMENT>0000937556-19-000148-index.html : 20190731
    <SEC-HEADER>0000937556-19-000148.hdr.sgml : 20190731
    <ACCEPTANCE-DATETIME>20190731161232
    ACCESSION NUMBER:		0000937556-19-000148
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		39
    CONFORMED PERIOD OF REPORT:	20190731
    ITEM INFORMATION:		Results of Operations and Financial Condition
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20190731
    DATE AS OF CHANGE:		20190731

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			MASIMO CORP
    		CENTRAL INDEX KEY:			0000937556
    		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845]
    		IRS NUMBER:				330368882
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1228

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-33642
    		FILM NUMBER:		19988866

    	BUSINESS ADDRESS:
    		STREET 1:		52 DISCOVERY
    		CITY:			IRVINE
    		STATE:			CA
    		ZIP:			92618
    		BUSINESS PHONE:		949-297-7000

    	MAIL ADDRESS:
    		STREET 1:		52 DISCOVERY
    		CITY:			IRVINE
    		STATE:			CA
    		ZIP:			92618
    </SEC-HEADER>
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    <FILENAME>masi-20190731x8k.htm
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    <DOCUMENT>
    <TYPE>EX-99.1
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    <DESCRIPTION>EXHIBIT 99.1
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    <FILENAME>masimoq22019earningspres.htm
    <DESCRIPTION>EXHIBIT 99.2
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    Document 3 - file: masimoq22019earningspres.htm

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    <FILENAME>masimoq22019nongaapsuppl.htm
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    Document 26 - file: masimoq22019nongaapdefs001.jpg

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    Document 27 - file: masimoq22019nongaapdefs002.jpg

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    Document 28 - file: masimoq22019nongaapdefs003.jpg

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    Document 29 - file: masimoq22019nongaapdefs004.jpg

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    Document 30 - file: masimoq22019nongaapdefs005.jpg

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    Document 31 - file: masimoq22019nongaapdefs006.jpg

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    <SEQUENCE>32
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    Document 32 - file: masimoq22019nongaapdefs007.jpg

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    <SEQUENCE>33
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    Document 33 - file: masimoq22019nongaapdefs008.jpg

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    <SEQUENCE>34
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    Document 34 - file: masimoq22019nongaapdefs009.jpg

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    <SEQUENCE>35
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    Document 35 - file: masimoq22019nongaapsuppl001.jpg

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    Document 36 - file: masimoq22019nongaapsuppl002.jpg

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    Document 37 - file: masimoq22019nongaapsuppl003.jpg

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    Document 38 - file: masimoq22019nongaapsuppl004.jpg

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    Document 39 - file: masimoq22019nongaapsuppl005.jpg

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