THIRD AMENDMENT TO THIRD AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP

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                                                                    EXHIBIT 10.4

                               THIRD AMENDMENT TO

                           THIRD AMENDED AND RESTATED

                        AGREEMENT OF LIMITED PARTNERSHIP

                       OF EOP OPERATING LIMITED PARTNERSHIP

                  THIS THIRD AMENDMENT TO THIRD AMENDED AND RESTATED AGREEMENT

OF LIMITED PARTNERSHIP OF EOP OPERATING LIMITED PARTNERSHIP (this "AMENDMENT")

is entered into on December 8, 2003, by EQUITY OFFICE PROPERTIES TRUST, a

Maryland real estate investment trust, as the general partner (the "GENERAL

PARTNER") of EOP Operating Limited Partnership, a Delaware limited partnership

(the "PARTNERSHIP").

                  WHEREAS, pursuant to Sections 14.1.B(3) and (4) of the

Agreement, the General Partner has determined that it is desirable to amend, in

the manner described below, the terms and conditions of the Series G Preferred

Units as set forth in Attachment G of the Agreement;

                   NOW, THEREFORE, in consideration of the premises set forth

above and for other good and valuable consideration, the receipt and sufficiency

of which hereby are