<SEC-DOCUMENT>0001093557-23-000089.txt : 20230317
<SEC-HEADER>0001093557-23-000089.hdr.sgml : 20230317
<ACCEPTANCE-DATETIME>20230317161410
ACCESSION NUMBER:		0001093557-23-000089
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20230316
FILED AS OF DATE:		20230317
DATE AS OF CHANGE:		20230317

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Dolan Matthew Vincent
		CENTRAL INDEX KEY:			0001914994

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-51222
		FILM NUMBER:		23742735

	MAIL ADDRESS:	
		STREET 1:		6340 SEQUENCE DR
		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>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2023-03-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001093557</issuerCik>
        <issuerName>DEXCOM INC</issuerName>
        <issuerTradingSymbol>DXCM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001914994</rptOwnerCik>
            <rptOwnerName>Dolan Matthew Vincent</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>6340 SEQUENCE DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92121</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP Corporate Strategy-Develop</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2023-03-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2303</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>115.0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33569</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">On December 15, 2021, Mr. Dolan adopted a 10b5-1 Plan which was amended on December 6, 2022.  This 10b5-1 Plan allows the orderly disposition of shares owned by Mr. Dolan.  The shares set forth above were sold pursuant to the 10b5-1 Plan.</footnote>
        <footnote id="F2">Included in this number are 33,569 unvested restricted stock units, 21,769 of which were granted on March 8, 2023 and shall vest through March 8, 2026, 7,704 of which were granted on March 8, 2022 and shall vest through March 8, 2025, 4,096 of which were granted on March 8, 2021 and shall vest through March 8, 2024.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Jereme Sylvain For: Matthew V Dolan</signatureName>
        <signatureDate>2023-03-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
