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        <issuerName>FEDERAL REALTY INVESTMENT TRUST</issuerName>
        <issuerTradingSymbol>FRT</issuerTradingSymbol>
        <issuerForeignTradingSymbol></issuerForeignTradingSymbol>
    </issuer>

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            <rptOwnerName>Lamb-Hale Nicole</rptOwnerName>
        </reportingOwnerId>
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            <rptOwnerStreet1>909 ROSE AVENUE SUITE 200</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NORTH BETHESDA</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20852</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
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            <isOfficer>0</isOfficer>
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            <isOther>0</isOther>
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    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Dawn M. Becker, by power of attorney</signatureName>
        <signatureDate>2026-10-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
