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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000931017-07-000027.txt : 20070518
<SEC-HEADER>0000931017-07-000027.hdr.sgml : 20070518
<ACCEPTANCE-DATETIME>20070518164159
ACCESSION NUMBER:		0000931017-07-000027
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070517
FILED AS OF DATE:		20070518
DATE AS OF CHANGE:		20070518

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Winthrop Realty Trust
		CENTRAL INDEX KEY:			0000037008
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				346513657
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		7 BULFINCH PLACE
		STREET 2:		SUITE 500 PO BOX 9507
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02114
		BUSINESS PHONE:		6175704614

	MAIL ADDRESS:	
		STREET 1:		7 BULFINCH PLACE
		STREET 2:		SUITE 500 PO BOX 9507
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02114

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST UNION REAL ESTATE EQUITY & MORTGAGE INVESTMENTS
		DATE OF NAME CHANGE:	19920703

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	FIRST UNION REALTY
		DATE OF NAME CHANGE:	19691012

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MANDIS STEVEN GEORGE
		CENTRAL INDEX KEY:			0001319846

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06249
		FILM NUMBER:		07865281

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		2123039493

	MAIL ADDRESS:	
		STREET 1:		HALCYON ASSET MANAGEMENT LLC
		STREET 2:		477 MADISON AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-05-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000037008</issuerCik>
        <issuerName>Winthrop Realty Trust</issuerName>
        <issuerTradingSymbol>FUR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001319846</rptOwnerCik>
            <rptOwnerName>MANDIS STEVEN GEORGE</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>HALCYON ASSET MANAGEMENT LLC</rptOwnerStreet1>
            <rptOwnerStreet2>477 MADISON AVENUE</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <transactionDate>
                <value>2007-05-17</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3238</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>6.4246</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>430441</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>see</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Shares sold were held by an investment fund in liquidation which is managed by Halcyon Structured Asset Management LP or its affiliate (&quot;Halcyon&quot;) an entity in which the Reporting Person serves as the Chief Investment Officer.  The Reporting Person derives no pecuniary interest from such shares and previously disclaimed beneficial ownership of such shares.</footnote>
        <footnote id="F2">Shares are held in investment funds managed by Halcyon.  In addition to the Shares listed, the investment funds own in the aggregate 936,000 shares of the Issuer's Series B-1 Preferred Shares which are immediately convertible into 5,200,000 of the Issuer's Common Shares.</footnote>
        <footnote id="F3">The Reporting Person disclaims beneficial ownership of all securities reported except to the extent of his pecuniary interest.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Steven G. Mandis</signatureName>
        <signatureDate>2007-05-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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