-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 GU5/qd9xgPWT2UwiVZeIOfGZSCV9+oho/jTD38jGhERe1I1E5H2Lq6oQShtJbL+p
 6aVvJoWI00/3HyVZAUKxkg==

<SEC-DOCUMENT>0001122681-09-000004.txt : 20091106
<SEC-HEADER>0001122681-09-000004.hdr.sgml : 20091106
<ACCEPTANCE-DATETIME>20091105175753
ACCESSION NUMBER:		0001122681-09-000004
CONFORMED SUBMISSION TYPE:	D
PUBLIC DOCUMENT COUNT:		1
ITEM INFORMATION:		Rule 506
FILED AS OF DATE:		20091106
DATE AS OF CHANGE:		20091105
EFFECTIVENESS DATE:		20091106

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Masthead Endeavour LLC
		CENTRAL INDEX KEY:			0001406127
		IRS NUMBER:				223681512
		STATE OF INCORPORATION:			ME
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		D
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	021-105704
		FILM NUMBER:		091162288

	BUSINESS ADDRESS:	
		STREET 1:		111 COMMERCIAL STREET
		STREET 2:		SUITE 302
		CITY:			Portland
		STATE:			ME
		ZIP:			04101
		BUSINESS PHONE:		(207) 780-0905

	MAIL ADDRESS:	
		STREET 1:		111 COMMERCIAL STREET
		STREET 2:		SUITE 302
		CITY:			Portland
		STATE:			ME
		ZIP:			04101
</SEC-HEADER>
<DOCUMENT>
<TYPE>D
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0603</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001406127</cik>
        <entityName>Masthead Endeavour LLC</entityName>
        <issuerAddress>
            <street1>111 COMMERCIAL STREET</street1>
            <street2>SUITE 302</street2>
            <city>Portland</city>
            <stateOrCountry>ME</stateOrCountry>
            <zipCode>04101</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>(207) 780-0905</issuerPhoneNumber>
        <jurisdictionOfInc>MAINE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Limited Liability Company</entityType>
        <yearOfInc>
            <overFiveYears>true</overFiveYears>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Braden</firstName>
                <middleName>M</middleName>
                <lastName>Bohrmann</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>111 Commercial street</street1>
                <street2>Ste 103</street2>
                <city>Portland</city>
                <stateOrCountry>ME</stateOrCountry>
                <zipCode>04101</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Manager of Managing Member, Masthead Venture Partners, LLC</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Stephen</firstName>
                <middleName>K</middleName>
                <lastName>Smith</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>111 Commercial street</street1>
                <street2>Ste 302</street2>
                <city>Portland</city>
                <stateOrCountry>ME</stateOrCountry>
                <zipCode>04101</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Manager of Managing Member, Masthead Venture Partners, LLC</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Richard</firstName>
                <middleName>W</middleName>
                <lastName>Levandov</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>55 Cambridge Pkwy</street1>
                <street2>Ste 103</street2>
                <city>Cambridge</city>
                <stateOrCountry>MA</stateOrCountry>
                <zipCode>02142</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Manager of Managing Member, Masthead Venture Partners, LLC</relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Investing</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>$1 - $1,000,000</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2009-10-23</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
            <isOptionToAcquireType>true</isOptionToAcquireType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>1</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>39200</totalOfferingAmount>
            <totalAmountSold>22686</totalAmountSold>
            <totalRemaining>16514</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>4</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>2937</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>2900</dollarAmount>
                <isEstimate>true</isEstimate>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Masthead Endeavour LLC</issuerName>
                <signatureName>Timothy P. Agnew</signatureName>
                <nameOfSigner>Timothy P. Agnew</nameOfSigner>
                <signatureTitle>Principal</signatureTitle>
                <signatureDate>2009-11-05</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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