<SEC-DOCUMENT>0001093557-20-000249.txt : 20200911
<SEC-HEADER>0001093557-20-000249.hdr.sgml : 20200911
<ACCEPTANCE-DATETIME>20200911185759
ACCESSION NUMBER:		0001093557-20-000249
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200909
FILED AS OF DATE:		20200911
DATE AS OF CHANGE:		20200911

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Blackford Quentin S.
		CENTRAL INDEX KEY:			0001612451

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-51222
		FILM NUMBER:		201171942

	MAIL ADDRESS:	
		STREET 1:		7475 LUSK BLVD.
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DEXCOM INC
		CENTRAL INDEX KEY:			0001093557
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				330857544
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6340 SEQUENCE DRIVE
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121
		BUSINESS PHONE:		8582000200

	MAIL ADDRESS:	
		STREET 1:		6340 SEQUENCE DRIVE
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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        <issuerName>DEXCOM INC</issuerName>
        <issuerTradingSymbol>DXCM</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>Blackford Quentin S.</rptOwnerName>
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            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92121</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Operating Officer &amp; CFO</officerTitle>
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    <footnotes>
        <footnote id="F1">Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of RSUs. This sale is mandated by the Issuer's election under its equity incentive plans to require the satisfaction of tax withholding obligations to be funded by a &quot;sell to cover&quot; transaction and does not represent a discretionary trade by the reporting person.</footnote>
        <footnote id="F2">Included in this number are 43,950 unvested restricted stock units, 12,727 of which were granted on March 8, 2020 and shall vest through March 8, 2023, 9,216 of which were granted on March 8, 2019 and shall vest through March 8, 2022, 6,417 of which were granted on March 8, 2018 and shall vest through March 8, 2021 and 15,590 of which were granted on September 7, 2017 and shall vest through September 7, 2021.</footnote>
        <footnote id="F3">On December 9, 2019, Mr. Blackford adopted a 10b5-1 Plan.  This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Blackford.   The shares set forth above were sold pursuant to the 10b5-1 Plan.</footnote>
        <footnote id="F4">This transaction was executed in multiple trades at prices ranging from $396.29 to $397.22. The price above reflects the weighted average sale price.  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 transactions were effected.</footnote>
        <footnote id="F5">This transaction was executed in multiple trades at prices ranging from $397.47 to $398.384. The price above reflects the weighted average sale price.  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 transactions were effected.</footnote>
        <footnote id="F6">This transaction was executed in multiple trades at prices ranging from $398.55 to $399.50. The price above reflects the weighted average sale price.  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 transactions were effected.</footnote>
        <footnote id="F7">This transaction was executed in multiple trades at prices ranging from $399.55 to $400.345. The price above reflects the weighted average sale price.  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 transactions were effected.</footnote>
        <footnote id="F8">This transaction was executed in multiple trades at prices ranging from $401.21 to $402.20. The price above reflects the weighted average sale price.  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 transactions were effected.</footnote>
        <footnote id="F9">This transaction was executed in multiple trades at prices ranging from $402.23 to $403.08. The price above reflects the weighted average sale price.  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 transactions were effected.</footnote>
        <footnote id="F10">This transaction was executed in multiple trades at prices ranging from $403.28 to $404.25. The price above reflects the weighted average sale price.  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 transactions were effected.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Jereme Sylvain For: Quentin S Blackford</signatureName>
        <signatureDate>2020-09-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
