<SEC-DOCUMENT>0000937556-20-000034.txt : 20200316
<SEC-HEADER>0000937556-20-000034.hdr.sgml : 20200316
<ACCEPTANCE-DATETIME>20200316185858
ACCESSION NUMBER:		0000937556-20-000034
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200312
FILED AS OF DATE:		20200316
DATE AS OF CHANGE:		20200316

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KIANI JOE E
		CENTRAL INDEX KEY:			0001228621

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33642
		FILM NUMBER:		20718727

	MAIL ADDRESS:	
		STREET 1:		4320 FOREST PARK AVENUE
		STREET 2:		SUITE 100
		CITY:			ST. LOUIS
		STATE:			MO
		ZIP:			63108

ISSUER:		

	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

	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>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_158439952071359.xml
<DESCRIPTION>FORM 4
<TEXT>
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            <rptOwnerStreet1>C/O MASIMO CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>52 DISCOVERY</rptOwnerStreet2>
            <rptOwnerCity>IRVINE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92618</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CEO and Chairman of the Board</officerTitle>
            <otherText></otherText>
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            <securityTitle>
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        </nonDerivativeHolding>
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            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
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                    <value>2250291</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
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                <directOrIndirectOwnership>
                    <value>I</value>
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                    <value>By Trust</value>
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                <directOrIndirectOwnership>
                    <value>I</value>
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                    <value>See Footnote</value>
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                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
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            </postTransactionAmounts>
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                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
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            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Non-Qualified Stock Option (Right to Buy)</value>
            </securityTitle>
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            </conversionOrExercisePrice>
            <transactionDate>
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            </transactionDate>
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                </transactionShares>
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                </transactionPricePerShare>
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                <footnoteId id="F8"/>
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                <value>2021-10-27</value>
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                <transactionFormType>4</transactionFormType>
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                <equitySwapInvolved>0</equitySwapInvolved>
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                    <value>66336</value>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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            <exerciseDate>
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                <value>Non-Qualified Stock Option (Right to Buy)</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
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                <transactionShares>
                    <value>23982</value>
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                <transactionPricePerShare>
                    <value>20.19</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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            <exerciseDate>
                <value>2012-10-27</value>
                <footnoteId id="F8"/>
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                <value>2021-10-27</value>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <sharesOwnedFollowingTransaction>
                    <value>257915</value>
                </sharesOwnedFollowingTransaction>
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    <footnotes>
        <footnote id="F1">The shares covered by this Form 4 were exercised and sold pursuant to a Rule 10b5-1 Sales Plan dated as of February 24, 2020, which is intended to comply with Rule 10b5-1 promulgated under the Securities Exchange Act of 1934, as amended.</footnote>
        <footnote id="F2">The price reported in Column 4 represents the weighted average sales price per share. The actual sales prices ranged from a low of $185.00 per share to a high of $187.85 per share. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer, or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.</footnote>
        <footnote id="F3">The price reported in Column 4 represents the weighted average sales price per share. The actual sales prices ranged from a low of $185.00 per share to a high of $186.81 per share. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer, or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.</footnote>
        <footnote id="F4">Shares held in four trusts for which Mr. Kiani is not the Trustee.</footnote>
        <footnote id="F5">Shares held in one trust for which Mr. Kiani is the sole trustee.</footnote>
        <footnote id="F6">Shares held in Masimo Retirement Savings Plan.</footnote>
        <footnote id="F7">Shares held by an immediate family member for which Mr. Kiani exercises voting and investment control.</footnote>
        <footnote id="F8">This option was granted on October 27, 2011 and was exercisable as the option vested. The option vested over a five year period, with 20% of the shares subject to the option vesting on each anniversary of the grant date.</footnote>
        <footnote id="F9">This option was granted on March 12, 2020 and is exercisable as the option vests.  The option vests over a 5 year period, with 20% of the shares subject to the option vesting each year starting March 22, 2021.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David J. Van Ramshorst, Attorney-In-Fact</signatureName>
        <signatureDate>2020-03-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
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</SEC-DOCUMENT>
