<SEC-DOCUMENT>0001127602-20-015780.txt : 20200507
<SEC-HEADER>0001127602-20-015780.hdr.sgml : 20200507
<ACCEPTANCE-DATETIME>20200507165002
ACCESSION NUMBER:		0001127602-20-015780
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20200507
FILED AS OF DATE:		20200507
DATE AS OF CHANGE:		20200507

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WEEKS WENDELL P
		CENTRAL INDEX KEY:			0001206158

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06571
		FILM NUMBER:		20857268

	BUSINESS ADDRESS:	
		STREET 1:		ONE RIVERFRONT PLZ
		CITY:			CORNING
		STATE:			NY
		ZIP:			14831
		BUSINESS PHONE:		607-974-9000

	MAIL ADDRESS:	
		STREET 1:		ONE RIVERFRONT PLZ
		CITY:			CORNING
		STATE:			NY
		ZIP:			14831

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Merck & Co., Inc.
		CENTRAL INDEX KEY:			0000310158
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		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>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-05-07</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001206158</rptOwnerCik>
            <rptOwnerName>WEEKS WENDELL P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>CORNING INCORPORATED</rptOwnerStreet1>
            <rptOwnerStreet2>1 RIVERFRONT PLAZA</rptOwnerStreet2>
            <rptOwnerCity>CORNING</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>14831</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-05-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5100</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2020-05-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>76.0207</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>100</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>35.19</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-05-07</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2011-08-04</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2020-08-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <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 $76.0201 to $76.0250, 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>
        <footnote id="F2">The option became exercisable in equal installments on 08/04/2011, 08/04/2012 and 08/04/2013.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Faye C. Brown as Attorney-in-Fact for Wendell P. Weeks</signatureName>
        <signatureDate>2020-05-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
