    <SEC-DOCUMENT>0000937556-19-000036-index.html : 20190226
    <SEC-HEADER>0000937556-19-000036.hdr.sgml : 20190226
    <ACCEPTANCE-DATETIME>20190226162618
    ACCESSION NUMBER:		0000937556-19-000036
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		31
    CONFORMED PERIOD OF REPORT:	20190226
    ITEM INFORMATION:		Results of Operations and Financial Condition
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20190226
    DATE AS OF CHANGE:		20190226

    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:			1229

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-33642
    		FILM NUMBER:		19633784

    	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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    <TYPE>8-K
    <SEQUENCE>1
    <FILENAME>masi-20180226x8k.htm
    <DESCRIPTION>8-K
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    <DOCUMENT>
    <TYPE>EX-99.1
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    <FILENAME>masi-20190226xex991.htm
    <DESCRIPTION>EXHIBIT 99.1
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    <SEQUENCE>3
    <FILENAME>q4fy2018investorpres.htm
    <DESCRIPTION>EXHIBIT 99.2
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    Document 3 - file: q4fy2018investorpres.htm

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    <DOCUMENT>
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    <SEQUENCE>4
    <FILENAME>q4fy2018supplementalsche.htm
    <DESCRIPTION>EXHIBIT 99.3
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