GUARANTY

                             [Winthrop Realty Trust]

      GUARANTY, dated as of December 16, 2005 (the "Guaranty"), by WINTHROP
REALTY TRUST, an Ohio business trust (the "Guarantor"), in favor of KEYBANK
NATIONAL ASSOCIATION, a national banking association having an address at 225
Franklin Street 18th Floor, Boston, Massachusetts 02110, as agent (KeyBank
National Association, in such capacity as agent, hereinafter referred to as
"Agent") for a syndicate of lenders (singly and collectively, the "Lenders") as
specifically provided in the Loan Agreement (as defined below).

                             INTRODUCTORY STATEMENT

      WHEREAS, pursuant to that certain Loan Agreement dated as of December 16,
2005 (as amended, supplemented or otherwise modified from time to time, the
"Loan Agreement") entered into by and among WRT REALTY L.P., a Delaware limited
partnership (the "Borrower"), the Agent, and the Lenders, the Agent and the
Lenders have agreed to make a loan to the Borrower in the aggregate principal
amount of up to $100,000,000.00 (the "Loan"), upon the terms and subject to the
conditions set forth therein.

      WHEREAS, the Guarantor is the general partner of the Borrower, and the
lending of money and other extensions of the Obligations by the Agent and the
Lenders to the Borrower will enhance and benefit the business activities and
interests of the Guarantor.

      WHEREAS, as a condition to making the Loans, the Agent and the Lenders
have required the Guarantor to execute and deliver this Guaranty, guaranteeing
the payment and performance of all Obligations arising under or pursuant to the
Loan Agreement.

      NOW THEREFORE, in consideration of the premises and in order to induce the
Agent and the Lenders to make the Loans and extend other financial
accommodations under the Loan Agreement, the Guarantor hereby agrees as follows:

      Section 1. Guaranty. The Guarantor hereby irrevocably and unconditionally
guarantees the punctual payment when due, whether at stated maturity, after
maturity, by acceleration or otherwise, and the punctual performance, of all
present and future Obligations under the Loan Agreement and each other Loan
Document, each as the same may be hereafter amended, modified, extended, renewed
or recast, including but not limited to the payment of $100,000,000.00, together
with interest and other charges thereon, as provided in the Loan Agreement and
the Note executed thereunder (the foregoing being herein referred to as the
"Guaranteed Obligations").

      Section 2. Waiver. The Guarantor hereby absolutely, unconditionally and
irrevocably waives, to the fullest extent permitted by law, (a) promptness,
diligence, notice of acceptance and any other notice with respect to this
Guaranty, (b) presentment, demand of payment, protest, notice of dishonor or
nonpayment and any other notice with respect to the Guaranteed Obligations, (c)
any requirement that the Agent protect, secure, perfect or insure any security
interest or Lien on any property subject thereto or exhaust any right or take


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any action against the Borrower or any other Person or any collateral (other
than Collateral pledged by the Borrower to the Agent, for its own benefit and
the benefit of the other Lenders, pursuant to the Security Documents), (d) any
and all right to assert any defense (other than the defense of indefeasible
payment), set-off, counterclaim or cross-claim of any nature whatsoever with
respect to this Guaranty (except as otherwise provided in Section 20(a)(iii)
hereof), the obligations of the Guarantor hereunder or the obligations of any
other person or party relating to this Guaranty or the obligations of the
Guarantor hereunder or otherwise with respect to the Guaranteed Obligations in
any action or proceeding brought by the Agent to collect the Guaranteed
Obligations or any portion thereof or to enforce the obligations of the
Guarantor under this Guaranty, and (e) any other action, event or precondition
to the enforcement of this Guaranty or the performance by the Guarantor of the
obligations hereunder.

      Section 3. Guaranty Absolute.

            (a) The Guarantor guarantees that, to the fullest extent permitted
      by law, the Guaranteed Obligations will be paid or performed strictly in
      accordance with their terms, regardless of any law, regulation or order
      now or hereafter in effect in any jurisdiction affecting any of such terms
      or the rights of the Agent with respect thereto.

            (b) No invalidity, irregularity, voidability, voidness or
      unenforceability of the Loan Agreement, the Note, or any other Loan
      Document or any other agreement or instrument relating thereto, or of all
      or any part of the Guaranteed Obligations or of any security therefor
      shall affect, impair or be a defense to this Guaranty.

            (c) This Guaranty is one of payment and performance, not collection,
      and the obligations of the Guarantor under this Guaranty are independent
      of the Guaranteed Obligations, and a separate action or actions may be
      brought and prosecuted against the Guarantor to enforce this Guaranty,
      irrespective of whether any action is brought against the Borrower or any
      Affiliate or Subsidiary thereof or whether the Borrower or any Affiliate
      or Subsidiary thereof is joined in any such action or actions.

            (d) The liability of the Guarantor under this Guaranty shall be
      absolute and unconditional irrespective of:

                  (i) any change in the manner, place or terms of payment or
      performance, and/or any change or extension of the time of payment or
      performance of, renewal or alteration of, any Guaranteed Obligation, any
      security therefor, or any liability incurred directly or indirectly in
      respect thereof, or any other amendment or waiver of or any consent to
      departure from the Loan Agreement or the Note or any other Loan Document,
      including any increase in the Guaranteed Obligations resulting from the
      extension of additional credit to the Borrower or any Subsidiary or
      Affiliate thereof or otherwise;


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                  (ii) any sale, exchange, release, surrender, realization upon
      any property by whomsoever at any time pledged or mortgaged to secure, or
      howsoever securing, all or any of the Guaranteed Obligations (other than
      the Collateral pledged to the Agent, for its own benefit and the benefit
      of the other Lenders, under the Security Documents), and/or any offset
      against such Guaranteed Obligations, or failure to perfect, or continue
      the perfection of, any Lien in any such property, or delay in the
      perfection of any such Lien, or any amendment or waiver of or consent to
      departure from any other guaranty for all or any of the Guaranteed
      Obligations;

                  (iii) any exercise or failure to exercise any rights against
      the Borrower or any Affiliate or Subsidiary thereof or others (including
      the Guarantor);

                  (iv) any settlement or compromise of any Guaranteed
      Obligation, any security therefor or any liability (including any of those
      hereunder) incurred directly or indirectly in respect thereof or hereof;

                  (v) any manner of application of Collateral, or proceeds
      thereof, to all or any of the Guaranteed Obligations, or any manner of
      sale or other disposition of any Collateral for all or any of the
      Guaranteed Obligations or any other assets of the Borrower or any
      Affiliate or Subsidiary thereof;

                  (vi) any change, restructuring or termination of the existence
      of the Borrower or any Affiliate or Subsidiary thereof;

                  (vii) the release of the Borrower or any other party, other
      than the Guarantor, now or hereafter liable upon or in respect of the Loan
      Documents; or

                  (viii) any other agreements or circumstance of any nature
      whatsoever which might otherwise constitute a defense available to, or a
      discharge of, this Guaranty and/or the obligations of the Guarantor
      hereunder, or a defense to, or discharge of, the Borrower or any Affiliate
      or Subsidiary thereof relating to this Guaranty or the obligations of the
      Guarantor hereunder or otherwise with respect to the Loan or other
      financial accommodations to the Borrower (other than the defense of
      indefeasible payment).

            (e) The Agent may at any time and from time to time (whether or not
      after revocation or termination of this Guaranty) without the consent of,
      or notice (except as shall be required by applicable statute and cannot be
      waived) to, the Guarantor, and without incurring responsibility to the
      Guarantor or impairing or releasing the obligations of the Guarantor
      hereunder, apply any sums by whomsoever paid or howsoever realized to any
      Guaranteed Obligation regardless of what Guaranteed Obligations remain
      unpaid.


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            (f) This Guaranty shall continue to be effective or be reinstated,
      as the case may be, if a claim is ever made upon the Agent for repayment
      or recovery of any amount or amounts received by the Agent in payment or
      on account of any of the Guaranteed Obligations as a result of laws
      relating to preferences, fraudulent transfers and fraudulent conveyances,
      and the Agent repays all or part of said amount by reason of any judgment,
      decree or order of any court or administrative body having jurisdiction
      over the Agent or its property, or any settlement or compromise of any
      such claim effected by the Agent with any such claimant (including the
      Borrower). In such event the Guarantor agrees that any such judgment,
      decree, order, settlement or compromise shall be binding upon the
      Guarantor, notwithstanding any revocation hereof or the cancellation of
      any note (including the Note) or other instrument evidencing any
      Guaranteed Obligation, and the Guarantor shall be and remain liable to the
      Agent hereunder for the amount so repaid or recovered to the same extent
      as if such amount had never originally been received by the Agent.

      Section 4. Continuing Guaranty. This Guaranty is a continuing one and
shall (a) remain in full force and effect until the indefeasible payment and
satisfaction in full of the Guaranteed Obligations, (b) be binding upon the
Guarantor, its successors and assigns, and (c) inure to the benefit of, and be
enforceable by, the Agent and the Lenders. All obligations to which this
Guaranty applies shall be conclusively presumed to have been created in reliance
hereon.

      Section 5. Representations, Warranties and Covenants. The Guarantor hereby
represents, warrants and covenants to and with the Agent and the Lenders that:

            (a) The Guarantor has the power to execute and deliver this Guaranty
      and to incur and perform its obligations hereunder;

            (b) The Guarantor has duly taken all necessary action to authorize
      the execution, delivery and performance of this Guaranty and to incur and
      perform its obligations hereunder;

            (c) No consent, approval, authorization or other action by, and no
      notice to or of, or declaration or filing with, any governmental or other
      public body, or any other Person, is required for the due authorization,
      execution, delivery and performance by the Guarantor of this Guaranty or
      the consummation of the transactions contemplated hereby;

            (d) The execution, delivery and performance by the Guarantor of this
      Guaranty does not and will not, with the passage of time or the giving of
      notice or both, violate or otherwise conflict with any term or provision
      of any material agreement, instrument, judgment, decree, order or any
      statute, rule or governmental regulation applicable to the Guarantor or
      result in the creation of any Lien upon any of its properties or assets
      pursuant thereto;


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            (e) This Guaranty has been duly authorized, executed and delivered
      by the Guarantor and constitutes the legal, valid and binding obligation
      of the Guarantor, and is enforceable against the Guarantor in accordance
      with its terms, except as enforcement thereof may be subject to the effect
      of any applicable bankruptcy, insolvency, reorganization, moratorium or
      similar law affecting creditors' rights generally, and general principles
      of equity (regardless of whether such enforcement is sought in a
      proceeding in equity or at law); and

      (f) The granting of the Loan to the Borrower will constitute a material
economic benefit to the Guarantor.

      Section 6. Affirmative Covenants. The Guarantor covenants and agrees that,
from the date hereof and so long as the Loan or the other Guaranteed Obligations
remain outstanding, the Guarantor shall pay, perform, observe and otherwise
comply with all of the affirmative covenants set forth in Article 7 of the Loan
Agreement that have been made by the Borrower therein with respect to the
Subsidiaries or the Loan Parties, but only to the extent that such covenants
were made with respect to the Guarantor.

      Section 7. Negative Covenants. The Guarantor covenants and agrees that,
from the date hereof and so long as the Loan or the other Guaranteed Obligations
remain outstanding, the Guarantor shall not take any action (or otherwise suffer
or permit to occur any event) contrary to the negative covenants set forth in
Article 8 of the Loan Agreement, as agreed by the Borrower therein with respect
to the Subsidiaries or the Loan Parties, but only to the extent that such
covenants were made with respect to the Guarantor.

      Section 8. Expenses. The Guarantor will, upon demand, reimburse the Agent
for any sums, costs, and expenses which the Agent and/or the Lenders may pay or
incur pursuant to the provisions of this Guaranty or in enforcing this Guaranty
or in enforcing payment of the Guaranteed Obligations or otherwise in connection
with the provisions hereof, including court costs, collection charges, and
reasonable attorneys' fees, together with interest thereon as specified in
Section 15 hereof.

      Section 9. Terms.

            (a) All terms defined in the Uniform Commercial Code of The
      Commonwealth of Massachusetts (as amended and in effect from time to time,
      the "UCC") and used herein shall have the meanings as defined in the UCC,
      unless the context otherwise requires.

            (b) The words "include," "includes" and "including" shall be deemed
      to be followed by the phrase "without limitation".


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            (c) All references herein to Sections and subsections shall be
      deemed to be references to Sections and subsections of this Guaranty
      unless the context shall otherwise require.

      Section 10. Amendments and Modification. No provision hereof shall be
modified, altered or limited except by written instrument expressly referring to
this Guaranty and to such provision, and executed by the party to be charged.

      Section 11. Waiver of Subrogation Rights. Until such time as all the
Guaranteed Obligations have been indefeasibly satisfied (including the
expiration of any applicable voidable preference period under the federal
bankruptcy laws), the Guarantor hereby waives and releases any and all rights
and claims it may now or hereafter have or acquire against the Borrower that
would constitute it a "creditor" of the Borrower for purposes of the federal
bankruptcy laws, including all rights of subrogation against the Borrower and
its property and all rights of indemnification, contribution and reimbursement
from the Borrower and its property, regardless of whether such rights arise in
connection with this Guaranty, by operation of law, pursuant to contract or
otherwise.

      Section 12. Remedies Upon Default.

            (a) Upon the occurrence and during the continuance of any Event of
      Default, in addition to any other rights and remedies which the Agent
      and/or the Lenders may have hereunder or at law, and not in limitation
      thereof, the Agent may, without notice to or demand upon the Borrower or
      the Guarantor, declare any Guaranteed Obligations immediately due and
      payable, and shall be entitled to enforce the obligations of the Guarantor
      hereunder.

            (b) The Agent's rights under this Guaranty shall be in addition to,
      and not in limitation of, all of the rights and remedies of the Agent
      and/or the Lenders under the Loan Documents. All rights and remedies of
      the Agent and/or the Lenders shall be cumulative and may be exercised in
      such manner and combination as the Agent and/or the Lenders, respectively,
      may determine.

      Section 13. Set-Off. After the occurrence and during the continuance of
any Event of Default, any Accounts, deposits, balances or other sums credited by
or due from the Agent, any affiliate of the Agent, or any of the Lenders, or
from any affiliate of any of the Lenders, to the Guarantor may to the fullest
extent not prohibited by applicable law at any time or from time to time,
without regard to the existence, sufficiency or adequacy of any other
collateral, and without notice or compliance with any other condition precedent
now or hereafter imposed by statute, rule of law or otherwise, all of which are
hereby waived to the fullest extent permitted by law, be set off, appropriated
and applied by the Agent against any or all of the Guaranteed Obligations
irrespective of whether demand shall have been made, in such manner as the Agent
in its sole and absolute discretion may determine. Within three (3) Business
Days of making any such set off, appropriation or application, the Agent agrees


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to notify Guarantor thereof, provided the failure to give such notice shall not
affect the validity of such set off or appropriation or application. ANY AND ALL
RIGHTS TO REQUIRE THE AGENT OR ANY OF THE LENDERS TO EXERCISE ITS RIGHTS OR
REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE LOAN, PRIOR TO
EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH ACCOUNTS, DEPOSITS, CREDITS
OR OTHER PROPERTY OF THE GUARANTOR, ARE HEREBY KNOWINGLY, VOLUNTARILY AND
IRREVOCABLY WAIVED.

      Section 14. Statute of Limitations. Any acknowledgment or new promise,
whether by payment of principal or interest or otherwise and whether by the
Borrower or others (including the Guarantor), with respect to any of the
Guaranteed Obligations shall, if the statute of limitations in favor of the
Guarantor against the Agent shall have commenced to run, toll the running of
such statute of limitations and, if the period of such statute of limitations
shall have expired, prevent the operation of such statute of limitations.

      Section 15. Interest. All amounts payable from time to time by the
Guarantor hereunder shall bear interest at the Default Rate, provided, that such
interest shall not be duplicative of any obligations payable under the Loan
Agreement.

      Section 16. Rights and Remedies Not Waived. No act, omission or delay by
the Agent shall constitute a waiver of its rights and remedies hereunder or
otherwise. No single or partial waiver by the Agent of any default hereunder or
right or remedy which it may have shall operate as a waiver of any other
default, right or remedy or of the same default, right or remedy on a future
occasion.

      Section 17. Admissibility of Guaranty. The Guarantor agrees that any copy
of this Guaranty signed by the Guarantor and transmitted by telecopier for
delivery to the Agent shall be admissible in evidence as the original itself in
any judicial or administrative proceeding, whether or not the original is in
existence.

      Section 18. Notices. All notices, requests and demands to or upon the
Agent, the Lenders or the Guarantor under this Guaranty shall be in writing and
given as provided in the Loan Agreement (and with respect to the Guarantor, c/o
the Borrower at the address of the Borrower as set forth in the Loan Agreement).

      Section 19. Counterparts. This Guaranty may be executed in any number of
counterparts and by the different parties hereto on separate counterparts, each
of which when so executed and delivered shall be an original and all of which
shall together constitute one and the same agreement.

      Section 20. CONSENT TO JURISDICTION; WAIVER OF JURY TRIAL; ETC.


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            (a) ANY LEGAL ACTION OR PROCEEDING WITH RESPECT TO THIS GUARANTY OR
      ANY SECURITY DOCUMENT MAY BE BROUGHT IN THE COURTS OF THE COMMONWEALTH OF
      MASSACHUSETTS OR OF THE UNITED STATES OF AMERICA FOR THE DISTRICT OF
      MASSACHUSETTS, AND, BY EXECUTION AND DELIVERY OF THIS GUARANTY, THE
      GUARANTOR HEREBY ACCEPTS FOR ITSELF AND IN RESPECT OF ITS PROPERTY,
      GENERALLY AND UNCONDITIONALLY, THE NONEXCLUSIVE JURISDICTION OF THE
      AFORESAID COURTS. THE GUARANTOR HEREBY KNOWINGLY, VOLUNTARILY AND
      IRREVOCABLY WAIVES, IN CONNECTION WITH ANY SUCH ACTION OR PROCEEDING, (i)
      TRIAL BY JURY, (ii) TO THE EXTENT IT MAY EFFECTIVELY DO SO UNDER
      APPLICABLE LAW, ANY OBJECTION, INCLUDING ANY OBJECTION TO THE LAYING OF
      VENUE OR BASED ON THE GROUNDS OF FORUM NON CONVENIENS, WHICH IT MAY NOW OR
      HEREAFTER HAVE TO THE BRINGING OF ANY SUCH ACTION OR PROCEEDING IN SUCH
      RESPECTIVE JURISDICTIONS AND (iii) THE RIGHT TO IMPOSE ANY SET-OFF,
      COUNTERCLAIM OR CROSS-CLAIM UNLESS SUCH SET-OFF, COUNTERCLAIM OR
      CROSS-CLAM COULD NOT, BY REASON OF ANY APPLICABLE FEDERAL OR STATE
      PROCEDURAL LAWS, BE INTERPOSED, PLEADED OR ALLEGED IN ANY OTHER ACTION.

            (b) The Guarantor irrevocably consents to the service of process of
      any of the aforementioned courts in any such action or proceeding by the
      mailing of copies thereof by certified mail, postage prepaid, to the
      Guarantor at its address determined pursuant to Section 18 hereof.

            (c) Nothing herein shall affect the right of the Agent to serve
      process in any other manner permitted by law or to commence legal
      proceedings or otherwise proceed against the Guarantor in any other
      jurisdiction.

            (d) The Guarantor hereby waives presentment, notice of dishonor and
      protests of all instruments included in or evidencing any of the
      Guaranteed Obligations, and any and all other notices and demands
      whatsoever (except as expressly provided herein).

      Section 21. GOVERNING LAW. THIS GUARANTY, THE SECURITY DOCUMENTS AND THE
GUARANTEED OBLIGATIONS SHALL BE GOVERNED IN ALL RESPECTS BY THE LAWS OF THE
COMMONWEALTH OF MASSACHUSETTS APPLICABLE TO CONTRACTS EXECUTED AND TO BE
PERFORMED IN SUCH STATE, WITHOUT GIVING EFFECT TO THE CONFLICT OF LAW PRINCIPLES
THEREOF.


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      Section 22. Captions; Separability.

            (a) The captions of the Sections and subsections of this Guaranty
      have been inserted for convenience only and shall not in any way affect
      the meaning or construction of any provision of this Guaranty.

            (b) If any term of this Guaranty shall be held to be invalid,
      illegal or unenforceable, the validity of all other terms hereof shall in
      no way be affected thereby.

      Section 23. Acknowledgment of Receipt. The Guarantor acknowledges receipt
of a copy of this Guaranty and each of the Loan Documents.

      Section 24. Entire Agreement. This Guaranty sets forth the entire
agreement and understanding of the Agent, the Lenders and the Guarantor with
respect to the matters covered hereby and, by accepting this Guaranty, the
Guarantor acknowledges that no oral or other understanding, agreements,
representations or warranties have been made and/or exist with respect to the
matters covered by this Guaranty or with respect to the obligations of the
Guarantor hereunder or otherwise, except as specifically set forth in this
Guaranty.

                            [SIGNATURE PAGE FOLLOWS]


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      IN WITNESS WHEREOF, the Guarantor has duly executed or caused this
Guaranty to be duly executed in The Commonwealth of Massachusetts as of the date
first above set forth.

                                                  WINTHROP REALTY TRUST


                                                  By:
                                                      --------------------------
                                                  Name:  Carolyn Tiffany
                                                  Title: Chief Operating Officer


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