<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2020-08-09</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001616543</issuerCik>
        <issuerName>Senseonics Holdings, Inc.</issuerName>
        <issuerTradingSymbol>SENS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001831357</rptOwnerCik>
            <rptOwnerName>PHC Holdings Corp</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2-38-5 NISHISHIMBASHI</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TOKYO</rptOwnerCity>
            <rptOwnerState>M0</rptOwnerState>
            <rptOwnerZipCode>105-8433</rptOwnerZipCode>
            <rptOwnerStateDescription>JAPAN</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isTenPercentOwner>true</isTenPercentOwner>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2941176</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Senior Secured Convertible Note</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-10-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>65359476</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">On August 9, 2020, the Issuer and PHC Holdings Corporation entered into a note purchase agreement pursuant to which the Issuer issued and sold $35 million in aggregate principal amount of its Senior Secured Convertible Note due October 31, 2024 (the &quot;2024 Note&quot;) on August 14, 2020 (the &quot;Closing Date&quot;). The Issuer also issued 2,941,176 shares of Common Stock to the Reporting Person as a financing fee on the Closing Date. At issuance of the 2024 Note, there were originally 65,359,476, shares of Common Stock issuable upon conversion of the 2024 Note, based on a conversion rate as of August 14, 2020 of 1,867.4136 shares of Common Stock per $1,000 principal amount of the 2024 Note (which conversion rate was subject to adjustment in accordance with the terms of the 2024 Note).</footnote>
    </footnotes>

    <remarks>On March 13, 2023, the Reporting Person entered into an agreement with the Issuer to exchange the 2024 Note reported herein, including accrued and unpaid interest thereon, for a warrant to purchase Common Stock, as described in the Form 4 filed by the Reporting Person on the date hereof.</remarks>

    <ownerSignature>
        <signatureName>/s/ Kaiju Yamaguchi</signatureName>
        <signatureDate>2023-03-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
