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    PUBLIC DOCUMENT COUNT:		67
    CONFORMED PERIOD OF REPORT:	20210102
    FILED AS OF DATE:		20210415
    DATE AS OF CHANGE:		20210415

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			MASIMO CORP
    		CENTRAL INDEX KEY:			0000937556
    		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845]
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    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			0102

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    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-33642
    		FILM NUMBER:		21827466

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    		STATE:			CA
    		ZIP:			92618
    		BUSINESS PHONE:		949-297-7000

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