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

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    <periodOfReport>2016-02-23</periodOfReport>

    <issuer>
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        <issuerName>Facebook Inc</issuerName>
        <issuerTradingSymbol>FB</issuerTradingSymbol>
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            <rptOwnerName>Koum Jan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O FACEBOOK, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>1601 WILLOW ROAD</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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                    <value>2528672</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Jan Koum, Trustee of The Jan Koum Trust III U/A/D 10/9/2014</value>
                    <footnoteId id="F22"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares of Class A Common Stock that were donated as a gift. The reporting person does not exercise voting or investment control, directly or indirectly, over the donated shares following this transfer.</footnote>
        <footnote id="F2">Shares held of record by Jan Koum, Trustee of The Butterfly Trust U/A/D 1/20/2004.</footnote>
        <footnote id="F3">The sales reported were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.</footnote>
        <footnote id="F4">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $105.13 to $106.125 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F5">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $106.13 to $107.12 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F6">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $107.13 to $107.45 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F7">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $102.77 to $103.76 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F8">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $103.77 to $104.76 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F9">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $104.78 to $105.77 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F10">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $105.78 to $106.77 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F11">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $106.78 to $106.90 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F12">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $105.64 to $106.63 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F13">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $106.64 to $107.63 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F14">The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $107.64 to $108.05 per share, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, 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 in this footnote.</footnote>
        <footnote id="F15">Shares held of record by Jan Koum and BNY Mellon Trust of Delaware, Co-Trustees of The Jan Koum Trust VIII U/A/D 01/29/2016.</footnote>
        <footnote id="F16">Shares held of record by Jan Koum and BNY Mellon Trust of Delaware, Co-Trustees of The Jan Koum Trust IV U/A/D 2/4/2015.</footnote>
        <footnote id="F17">Shares held of record by Jan Koum and BNY Mellon Trust of Delaware, Co-Trustees of The Jan Koum Trust V U/A/D 4/29/2015.</footnote>
        <footnote id="F18">Shares held of record by Jan Koum and BNY Mellon Trust of Delaware, Co-Trustees of The Jan Koum Trust VI U/A/D 8/5/2015.</footnote>
        <footnote id="F19">Shares held of record by Jan Koum and BNY Mellon Trust of Delaware, Co-Trustees of The Jan Koum Trust VII U/A/D 10/20/2015.</footnote>
        <footnote id="F20">Shares held of record by Jan Koum, Trustee of The Jan Koum Trust I U/A/D 4/29/2014.</footnote>
        <footnote id="F21">Shares held of record by Jan Koum, Trustee of The Jan Koum Trust II U/A/D 8/5/2014.</footnote>
        <footnote id="F22">Shares held of record by Jan Koum, Trustee of The Jan Koum Trust III U/A/D 10/9/2014.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Michael Johnson as attorney-in-fact for Jan Koum</signatureName>
        <signatureDate>2016-02-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
