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                             ELEVENTH AMENDMENT TO

                        AGREEMENT OF LIMITED PARTNERSHIP

                                       OF

                       EOP OPERATING LIMITED PARTNERSHIP


         THIS ELEVENTH AMENDMENT TO AGREEMENT OF LIMITED PARTNERSHIP OF EOP
OPERATING LIMITED PARTNERSHIP (this "Amendment"), dated as of May 1, 2000, is
entered into by EQUITY OFFICE PROPERTIES TRUST, a Maryland real estate
investment trust, as managing general partner (the "Managing General Partner")
of EOP Operating Limited Partnership (the "Partnership"), for itself and on
behalf of the Limited Partners of the Partnership.

                                  WITNESSETH:

         WHEREAS, the Managing General Partner and the Limited Partners have
entered into the Agreement of Limited Partnership of EOP Operating Limited
Partnership, dated as of July 3, 1997, as the same has been amended through the
date hereof (the "Agreement"); and

         WHEREAS, the Managing General Partner, pursuant to the authority
granted to it under Sections 14.1.A and 14.1.B(4) of the Agreement, as
applicable, desires to amend Sections 7.4, 8.5.C and 14.1.B of the Agreement as
set forth herein, and the Managing General Partner, for itself and, to the
extent this action is taken pursuant to Section 14.1.A of the Agreement, as the
holder of a majority of the Percentage Interests of the Limited Partners, has
approved such amendment.

         NOW, THEREFORE, in consideration of the premises and for other good
and valuable consideration, the receipt and sufficiency of which hereby are
acknowledged, the Managing General Partner hereby amends the Agreement as
follows:

         1.      Amendment to Section 7.4 of Agreement.  Section 7.4 of the
Agreement is hereby amended to add the following new Paragraph F:

                 F.               Funding for Certain Capital Transactions.  In
         the event that the Managing General Partner shall undertake to acquire
         (whether by merger, consolidation, purchase, or otherwise) the assets
         or equity interests of another Person and such acquisition shall
         require the payment of cash by the Managing General Partner (whether
         to such Person or to any other selling party or parties in such
         transaction
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         or to one or more creditors, if any, of such Person or such selling
         party or parties), (i) the Partnership shall advance to the Managing
         General Partner the cash required to consummate such acquisition if,
         and to the extent that, such cash is not to be obtained by the
         Managing General Partner through an issuance of Shares described in
         Section 4.2 or pursuant to a transaction described in Section 7.5.B,
         (ii) the Managing General Partner shall immediately, upon consummation
         of such acquisition, transfer to the Partnership (or cause to be
         transferred to the Partnership), in full and complete satisfaction of
         such advance and as required by Section 7.5, the assets or equity
         interests of such Person acquired by the Managing General Partner in
         such acquisition, and (iii) pursuant to and in accordance with Section
         4.2 and Section 7.5.B, the Partnership shall issue to the Managing
         General Partner Partnership Interests and/or rights, options, warrants
         or convertible or exchangeable securities of the Partnership having
         designations, preferences and other rights that are substantially the
         same as those of any additional Shares, other equity securities, New
         Securities and/or Convertible Funding Debt, as the case may be, issued
         by the Managing General Partner in connection with such acquisition
         (whether issued directly to participants in the acquisition
         transaction or to third parties in order to obtain cash to complete
         the acquisition).  In addition to, and without limiting the foregoing,
         in the event that the Managing General Partner engages in a
         transaction in which (x) the Managing General Partner (or a wholly
         owned direct or indirect Subsidiary of the Managing General Partner)
         merges with another entity (referred to as the "Parent Entity") that
         is organized in the "UPREIT format" (i.e., where the Parent Entity
         holds substantially all of its assets and conducts substantially all
         of its operations through a partnership, limited liability company or
         other entity (referred to as an "Operating Entity")) and the Managing
         General Partner survives such merger, (y) such Operating Entity merges
         with or is otherwise acquired by the Partnership in exchange in whole
         or in part for Partnership Interests, and (z) the Managing General
         Partner is required or elects to pay part of the consideration in
         connection with such merger involving the Parent Entity in the form of
         cash and part of the consideration in the form of Shares, the
         Partnership shall distribute to the Managing General Partner with
         respect to its existing Partnership Interest an amount of cash
         sufficient to complete such transaction and the Managing General
         Partner shall cause the Partnership to cancel a number of Partnership
         Units (rounded to the nearest whole number) held by the Managing
         General Partner equal to the product attained by multiplying the
         number of additional Shares of the Managing General Partner that the
         Managing General Partner would have issued to the Parent Entity or





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         the owners of the Parent Entity in such transaction if the entire
         consideration therefor were to have been paid in Shares by a fraction,
         the numerator of which is one and the denominator of which is the
         Conversion Factor.

         2.      Amendment to Section 8.5.C of Agreement.  Section 8.5.C of the
Agreement is hereby amended to add the following proviso at the end of the
existing first sentence of Section 8.5.C:

         ; provided, however, that the Managing General Partner, in its sole
         discretion, may shorten the required notice period of not less than
         twenty (20) business days prior to the record date to determine the
         shareholders eligible to vote upon a merger transaction (but not any
         of the other transactions covered by this Section 8.5.C.) to a period
         of not less than ten (10) calendar days (thereby continuing to afford
         the holders of Units the opportunity to redeem Units under Section 8.6
         on or prior to the record date for the shareholder vote on the merger
         transaction) so long as (i) the General Partner Entity will be the
         surviving entity in such merger transaction, (ii) immediately
         following the merger transaction, Persons who held voting securities
         of the General Partner Entity immediately prior to such merger
         transaction will hold, solely by reason of the ownership of voting
         securities of the General Partner Entity immediately prior to the
         merger transaction, voting securities of the General Partner Entity
         representing not less than fifty-one percent (51%) of the total
         combined voting power of all outstanding voting securities of the
         General Partner Entity after such merger, and (iii) in the event that
         in connection with such merger transaction the Partnership will merge
         with another entity, the Partnership will be the surviving entity in
         such merger.

         3.      Amendment to Section 14.1.B of Agreement. Section 14.1.B of
the Agreement hereby is amended by deleting the last sentence of Section 14.1.B
in its entirety and by substituting therefor the following:

         The Managing General Partner shall notify the Limited Partners when
         any action under this Section 14.1.B is taken in the next regular
         communication to the Limited Partners; provided, however, that no
         notice need be given of any amendment of this Agreement to reflect the
         admission, substitution, termination, or withdrawal of Partners in
         accordance with this Agreement (whether or not effected through the
         replacement of Exhibit A with an amended Exhibit A).  For purposes of
         the immediately preceding sentence, notwithstanding any other means by
         which the Managing General Partner may provide any such notice to the
         Limited Partners, such notice requirement shall be deemed to





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         have been satisfied upon the filing with the Securities and Exchange
         Commission by the Partnership of any amendment to this Agreement
         permitted under this Section 14.1.B as an exhibit to (i) a
         registration statement filed by the Partnership under the Securities
         Act or (ii) any report or other document filed by the Partnership
         under the Exchange Act.

         4.      Definitions; Full Force and Effect.   All capitalized terms
used in this Amendment and not otherwise defined herein shall have the meanings
assigned to them in the Agreement.  Except as modified herein, all terms and
conditions of the Agreement shall remain in full force and effect, which terms
and conditions the Managing General Partner, for itself and the Limited
Partners, hereby ratifies and affirms.

         IN WITNESS WHEREOF, the undersigned has executed and delivered this
Amendment as of the date first set forth above.

                               EQUITY OFFICE PROPERTIES TRUST,
                               a Maryland real estate investment trust, as
                               Managing General Partner of EOP
                               Operating Limited Partnership and on
                               behalf of the Limited Partners thereof


                               By:  /s/ STANLEY M. STEVENS
                                    --------------------------------
                                        Name:  Stanley M. Stevens
                                        Title: Executive Vice President






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