<SEC-DOCUMENT>0001127602-25-005928.txt : 20250220
<SEC-HEADER>0001127602-25-005928.hdr.sgml : 20250220
<ACCEPTANCE-DATETIME>20250220160154
ACCESSION NUMBER:		0001127602-25-005928
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250219
FILED AS OF DATE:		20250220
DATE AS OF CHANGE:		20250220

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Oosthuizen Johannes Jacobus
		CENTRAL INDEX KEY:			0001916310
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06571
		FILM NUMBER:		25645171

	MAIL ADDRESS:	
		STREET 1:		2000 GALLOPING HILL RD
		CITY:			KENILWORTH
		STATE:			NJ
		ZIP:			07033

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Merck & Co., Inc.
		CENTRAL INDEX KEY:			0000310158
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		ORGANIZATION NAME:           	03 Life Sciences
		IRS NUMBER:				221918501
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2000 GALLOPING HILL ROAD
		CITY:			KENILWORTH
		STATE:			NJ
		ZIP:			07033
		BUSINESS PHONE:		908-740-4000

	MAIL ADDRESS:	
		STREET 1:		2000 GALLOPING HILL ROAD
		CITY:			KENILWORTH
		STATE:			NJ
		ZIP:			07033

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Merck & Co. Inc.
		DATE OF NAME CHANGE:	20091103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SCHERING PLOUGH CORP
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-02-19</periodOfReport>

    <issuer>
        <issuerCik>0000310158</issuerCik>
        <issuerName>Merck &amp; Co., Inc.</issuerName>
        <issuerTradingSymbol>MRK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001916310</rptOwnerCik>
            <rptOwnerName>Oosthuizen Johannes Jacobus</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>MERCK &amp; CO., INC.</rptOwnerStreet1>
            <rptOwnerStreet2>126 EAST LINCOLN AVENUE</rptOwnerStreet2>
            <rptOwnerCity>RAHWAY</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07065</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>President, U.S. Market</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-02-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>8500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>84.0876</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>30705.474</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $84.0700 to $84.1000, inclusive. The reporting person undertakes to provide to Merck &amp; Co., Inc., any security holder of Merck &amp; Co., Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above in this footnote.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Kelly E. W. Grez, as attorney-in-fact for Johannes Oosthuizen</signatureName>
        <signatureDate>2025-02-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
