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                                                                EXHIBIT 10.1.4

                                SEVENTH AMENDMENT
                       TO AGREEMENT OF LIMITED PARTNERSHIP
                      OF EOP OPERATING LIMITED PARTNERSHIP

            THIS SEVENTH AMENDMENT TO AGREEMENT OF LIMITED PARTNERSHIP OF EOP
OPERATING LIMITED PARTNERSHIP (this "Amendment"), dated September 30, 1998, is
entered into by EQUITY OFFICE PROPERTIES TRUST, a Maryland real estate
investment trust, as managing general partner (the "General Partner") of EOP
Operating Limited Partnership, a Delaware limited partnership (the
"Partnership"), for itself and on behalf of the limited partners of the
Partnership.

            WHEREAS, on the date hereof, BRE/WORLDWIDE L.L.C. ("BRE") is
receiving 6,861,166 Class B units of limited partnership interest ("OP Units")
in the Partnership in exchange for, among other things, the office property
known as Worldwide Plaza in New York, New York (the "Property") pursuant to a
closing under, and as more particularly described in, that certain Agreement of
Purchase and Sale dated as of July 31, 1998 by and between the Partnership, BRE
and others (the "Purchase Agreement"); and

            WHEREAS, BRE has assigned certain of the OP Units to its constituent
members as set forth on Schedule I (the "BRE Partnerships") which in turn have
assigned certain of the OP Units to their constituent partners as set forth on
Schedule 2 (the "BRE Partners" and together with BRE and the BRE Partnerships,
the "BRE Entities"); and

            WHEREAS, the BRE Entities set forth on Schedule 3, Column A (the
"Electing BRE Entities") have elected to exercise their Redemption Rights under
the Partnership Agreement as evidenced by that certain Certificate of Election
dated September _, 1998; and

            WHEREAS, BRE, the BRE Partnerships and the non-Electing BRE Entities
set forth on Schedule 3, Column B (collectively, the "Remaining BRE Entities")
desire to become parties to the Partnership Agreement and to be bound by all the
terms, conditions and other provisions of this Amendment and the Partnership
Agreement; and

            WHEREAS, pursuant to the authority granted to the General Partner
under the Agreement of Limited Partnership of the Partnership dated as of July
3, 1997, and as amended thereafter (the "Partnership Agreement"), the General
Partner desires to amend the Partnership Agreement to admit the Remaining BRE
Entities as a result of the foregoing transactions, and to reflect in its
records the admission of the Remaining BRE Entities as Additional Limited
Partners and the holders of the OP Units; and

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

            1. The Remaining BRE Entities (i) are hereby admitted as Additional
Limited Partners in accordance with Section 12.2 of this Partnership Agreement
holding the OP Units and (ii) hereby agree

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to become parties to the Partnership Agreement and to be bound by all of the
terms, conditions and other provisions of the Partnership Agreement.

            2. Exhibit A to the Partnership Agreement hereby is amended by
inserting in such Exhibit A, the information set forth on Exhibit "A-1" attached
to this Amendment to reflect (i) those Remaining BRE Entities which remain as
Limited Partners subsequent to the consummation of all transactions contemplated
by, and/or closed immediately subsequent to, the closing of the Purchase
Agreement and (ii) the number of additional OP Units held by the General Partner
as a result of the election by the Electing BRE Entities to redeem the OP Units
set forth on Schedule 3, Column A.

            3. Notwithstanding any provision in the Partnership Agreement to the
contrary, the Specified Redemption Date with respect to the OP Units shall be
September __, 1998.

            4. The General Partner agrees that, notwithstanding the provisions
of Section 2.C of Exhibit C to the Partnership Agreement, for purposes of
allocating items of income, gain, loss and deduction with respect to the Assets
(as defined in the Purchase Agreement) in the manner required by Section 704(c)
of the Internal Revenue Code, as amended, the Partnership shall employ, and
shall cause any entity controlled by the Partnership which holds title to any of
the Assets to employ, the "traditional method" as set forth in Treasury
Regulations section 1.704-3(b).

            5. Time is of the essence of each and every provision of this
Amendment.

            6. All capitalized terms used in this Amendment and not otherwise
defined shall have the meanings assigned in the Partnership Agreement. Except as
modified herein, all terms and conditions of the Partnership Agreement shall
remain in full force and effect, which terms and conditions the General Partner
hereby ratifies and affirms.

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

                     GENERAL PARTNER:

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

                     By:  /s/ STANLEY STEVENS
                          -------------------------------------
                          Name:    Stanley Stevens
                          Title:   EVP

                     REMAINING BRE ENTITIES:

                     BRE/WORLDWIDE L.L.C., a Delaware limited liability company

                     By:  /s/ THOMAS J. SAYLAK
                          -------------------------------------
                          Name:    Thomas J. Saylak
                          Title:   Vice President

                     BLACKSTONE REAL ESTATE PARTNERS I L.P.
                     BLACKSTONE REAL ESTATE PARTNERS TWO L.P.
                     BLACKSTONE REAL ESTATE PARTNERS III L.P.
                     BLACKSTONE REAL ESTATE PARTNERS IV L.P.
                     BLACKSTONE RE CAPITAL PARTNERS L.P.
                     BLACKSTONE RE CAPITAL PARTNERS II L.P.
                     BLACKSTONE RE OFFSHORE CAPITAL PARTNERS L.P.

                     By:  Blackstone Real Estate Associates L.P., a Delaware
                          limited partnership, general partner

                          By:  BREA L.L.C., a Delaware limited liability
                               company, general partner

                               By:   /s/ STEPHEN A. SCHWARZMAN
                                     -----------------------------
                                     Name:   Stephen A. Schwarzman
                                     Title:  Founding Member

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                     WW WEST "A" ASSOCIATES L.P.

                     By:   GLK West "A" Corp., general partner

                           By:    /s/
                                  ------------------------------------
                                  Name:
                                  Title:

                     BLACKSTONE REAL ESTATE HOLDINGS L.P.

                     By:   BREA L.L.C., a Delaware limited liability
                           company, general partner

                           By:    /s/
                                  ------------------------------------
                                  Name:
                                  Title:

                     TRAVELERS INSURANCE CO.

                     By:   /s/
                           --------------------------------------------
                           Name:   John W. Fletcher
                           Title:  Second Vice President

                     BLACKSTONE REAL ESTATE ASSOCIATES L.P.

                     By:   BREA L.L.C., a Delaware limited liability
                           company, general partner

                           By:   /s/
                                 ---------------------------------
                                 Name:
                                 Title:

                     BREA L.L.C.

                     By:   /s/
                           ------------------------------------------
                           Name:
                           Title:

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                     CENTAUR PARTNERS IV L.P.

                     By:   SB WESTRIDGE, INC.

                           By:   /s/
                                 ------------------------------------
                                 Name:
                                 Title:

                     SB WESTRIDGE, INC.

                     By:   /s/
                           -----------------------------------
                           Name:
                           Title:

                     BLACKSTONE REAL ESTATE
                     CAPITAL ASSOCIATES L.P.

                     By:   BCAS L.L.C., general partner

                           By:   /s/ STEPHEN A. SCHWARZMAN
                                 ------------------------------------
                                 Name:    Stephen A. Schwarzman
                                 Title:

                     BLACKSTONE REAL ESTATE
                     MANAGEMENT ASSOCIATES L.P.

                     By:   /s/ STEPHEN A. SCHWARZMAN
                           -------------------------------------------
                           Name:   Stephen A. Schwarzman
                           Title:

                     BLACKSTONE GROUP HOLDINGS L.P.

                     By:   Blackstone Group Holdings L.L.C., general partner

                           By:   /s/ STEPHEN A. SCHWARZMAN
                                 ---------------------------------------
                                 Name:    Stephen A. Schwarzman
                                 Title:   Founding Member

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                     BLACKSTONE FAMILY REAL
                     ESTATE PARTNERSHIP L.P.

                     By:   Blackstone Real Estate Management Associates
                           L.P., general partner

                           By:   /s/ STEPHEN A. SCHWARZMAN
                                 -----------------------------
                                 Name:   Stephen A. Schwarzman
                                 Title:

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                                                                  EXHIBIT 10.1.5

                               EIGHTH AMENDMENT TO

                        AGREEMENT OF LIMITED PARTNERSHIP

                                       OF

                        EOP OPERATING LIMITED PARTNERSHIP

       This Eighth Amendment (this "Amendment") is made as of December 14, 1998
by and among Equity Office Properties Trust, a Maryland real estate investment
trust, as managing general partner (the "Company" or the "Managing General
Partner") of EOP Operating Limited Partnership, a Delaware limited partnership
(the "Partnership"), and as attorney-in-fact for the Persons named on Exhibit A
to the Agreement of Limited Partnership of EOP Operating Limited Partnership,
dated as of July 3, 1997, as amended, (the "Partnership Agreement") for the
purpose of amending the Partnership Agreement. Capitalized terms used herein and
not defined shall have the meanings given to them in the Partnership Agreement.

       WHEREAS, the Company has issued and sold 4,600,000 8 5/8% Series C
Cumulative Redeemable Preferred Shares of Beneficial Interest (the "Series C
Preferred Shares") in an underwritten public offering (the "Offering") made
pursuant to the Company's effective shelf registration statement on Form S-3
(Reg. No. 333-58729), its prospectus dated July 22, 1998, and its related
prospectus supplement dated December 1, 1998; and

       WHEREAS, the Managing General Partner has determined that it is necessary
and desirable to amend the Partnership Agreement (i) to create additional
Partnership Units having designations, preferences and other rights which are
substantially the same as the economic rights of the Series C Preferred Shares.

       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 Partnership
Agreement as follows:

       1. Article I of the Partnership Agreement is hereby amended by adding the
following definitions:

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       "Series C Preferred Shares" means the 8 5/8% Series C Cumulative
Redeemable Preferred Shares of Beneficial Interest of the Company issued and
sold in the Offering; and

       "Series C Preferred Units" means the series of Partnership Units
representing units of Limited Partnership Interests designated as the 8 5/8%
Series C Cumulative Redeemable Preferred Units with the designations,
preferences and other rights set forth herein.

       2.     In accordance with Section 4.2.A of the Partnership Agreement, set
forth below are the terms and conditions of the Series C Preferred Units hereby
established and issued to the Company in connection with the Partnership Merger.

       A.     Designation and Number. A series of Partnership Units designated
as Series C Preferred Units is hereby established. The number of Series C
Preferred Units shall be 4,600,000.

       B.     Rank. The Series C Preferred Units will, with respect to
distribution rights and rights upon liquidation, dissolution or winding up of
the Partnership, rank (a) senior to the Class A Units, Class B Units and all
Partnership Interests ranking junior to the Series C Preferred Units; (b) on a
parity with the Series A Preferred Units, the Series B Preferred Units and all
other Partnership Interests issued by the Partnership the terms of which
specifically provide that such Partnership Interests rank on a parity with the
Series C Preferred Units; and (c) junior to all Partnership Interests issued by
the Partnership the terms of which specifically provide that such Partnership
Interests rank senior to the Series C Preferred Units.

       C.     Distributions.

       (i)    Pursuant to Section 5.1 of the Partnership Agreement, holders of
Series C Preferred Units shall be entitled to receive, out of Available Cash,
cumulative preferential distributions of Available Cash at the rate of 8 5/8% of
the $25.00 liquidation preference per annum (equivalent to a fixed annual amount
of $2.15625 per unit). Such distributions shall accumulate on a daily basis and
be cumulative from the date of original issuance (December 8, 1998) and shall be
payable quarterly in arrears on March 15, June 15, September 15 and December 15
of each year or, if not a business day, the next succeeding business day (each a
"Series C Preferred Unit Distribution Payment Date"), commencing March 15, 1999.
Any distribution payable on the Series C Preferred Units for any partial
distribution period will be computed on the basis of a 360-day year consisting
of twelve 30-day months.

       (ii)   No distributions on Series C Preferred Units shall be authorized
or paid or set apart for payment at such time as the terms and provisions of any

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agreement of the Partnership, including any agreement relating to its
indebtedness, prohibits such authorization, payment or setting apart for payment
or provides that such authorization, payment or setting apart for payment would
constitute a breach thereof, or a default thereunder, or if such authorization
or payment shall be restricted or prohibited by law.

       (iii)  Notwithstanding the foregoing, distributions with respect to the
Series C Preferred Units will accumulate whether or not the terms and provisions
set forth in Section 2.C.(ii) at any time prohibit the current payment of
distributions, whether or not there is sufficient Available Cash for such
distributions and whether or not such distributions are authorized. Accumulated
but unpaid distributions on the Series C Preferred Units will accumulate as of
the Series C Preferred Unit Distribution Payment Date on which they first become
payable.

       (iv)   When distributions are not paid in full (or a sum sufficient for
such full payment is not so set apart) upon the Series C Preferred Units and any
other Partnership Interests ranking on a parity as to distributions with the
Series C Preferred Units, all distributions authorized upon the Series C
Preferred Units and any other Partnership Interests ranking on a parity as to
distributions with the Series C Preferred Units shall be authorized pro rata so
that the amount of distributions authorized per Partnership Unit of Series C
Preferred Units and such other Partnership Interests shall in all cases bear to
each other the same ratio that accumulated distributions per Partnership Unit on
the Series C Preferred Units and such other Partnership Interests (which shall
not include any accumulation in respect of unpaid distributions for prior
distribution periods if such other Partnership Interests do not have a
cumulative distribution) bear to each other. No interest, or sum of money in
lieu of interest, shall be payable in respect of any distribution payment or
payments on Series C Preferred Units which may be in arrears.

       (v)    Except as provided in Section 2.B.(iv), unless full cumulative
distributions on the Series C Preferred Units have been or contemporaneously are
authorized and paid or authorized and a sum sufficient for the payment thereof
is set apart for payment for all past distribution periods and the then current
distribution period, no distributions (other than in Partnership Interests
ranking junior to the Series C Preferred Units as to distributions and upon
liquidation) shall be authorized or paid or set aside for payment nor shall any
other distribution be authorized or made upon the Class A Units, the Class B
Units, or any other Partnership Interests ranking junior to or on a parity with
the Series C Preferred Units as to distributions or upon liquidation, nor shall
any Class A Units, Class B Units, or any other Partnership Interests ranking
junior to or on a parity with the Series C Preferred Shares as to distributions
or upon liquidation be redeemed, purchased or otherwise acquired for any
consideration (or any moneys be paid to or made available for a sinking fund for
the redemption of any such units or other

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Partnership Interests) by the Partnership (except by conversion into or
exchange for Partnership Interests ranking junior to the Series C Preferred
Units as to distributions and upon liquidation).

       (vi)   Holders of the Series C Preferred Units shall not be entitled to
any distribution, whether payable in cash, property or Partnership Units in
excess of full cumulative distributions on the Series C Preferred Units as
described above. Any distribution payment made on the Series C Preferred Units
shall first be credited against the earliest accumulated but unpaid distribution
due with respect to such Series C Preferred Units which remains payable.

       D.     Allocations.

       Allocations of the Partnership's items of income, gain, loss and
deduction shall be allocated among holders of Series C Preferred Units in
accordance with Article VI of the Partnership Agreement.

       E.     Liquidation Preference.

       (i)    Upon any voluntary or involuntary liquidation, dissolution or
winding up of the affairs of the Partnership, the holders of Series C Preferred
Units then outstanding are entitled to be paid out of the assets of the
Partnership available for distribution to the Partners pursuant to Section
13.2.A of the Partnership Agreement a liquidation preference of $25.00 per
Series C Preferred Unit, plus an amount equal to any accumulated and unpaid
distributions to the date of payment, before any distribution of assets is made
to holders of Class A Units, Class B Units or any other Partnership Interests
that rank junior to the Series C Preferred Units as to liquidation rights.

       (ii)   In the event that, upon any such voluntary or involuntary
liquidation, dissolution or winding up, the available assets of the Partnership
are insufficient to pay the amount of the liquidating distributions on all
outstanding Series C Preferred Units and the corresponding amounts payable on
all other Partnership Interests ranking on a parity with the Series C Preferred
Units in the distribution of assets, then such assets shall be allocated among
the Series C Preferred Units, as a class, and each class or series of such other
such Partnership Interests, as a class, in proportion to the full liquidating
distributions to which they would otherwise be respectively entitled.

       (iii)  After payment of the full amount of the liquidating distributions
to which they are entitled, the holders of Series C Preferred Units will have no
right or claim to any of the remaining assets of the Partnership.

       (iv)   The consolidation or merger of the Partnership with or into any
other partnership, corporation, trust or entity or of any other partnership,
corporation, trust or other entity with or into the Partnership or the sale,
lease or
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conveyance of all or substantially all of, the property or business of
the Partnership, shall not be deemed to constitute a liquidation, dissolution or
winding up of the Partnership for purposes of this Section 2.E.

       F.     Redemption.

       In connection with a redemption by the Company of any or all of the
Series C Preferred Shares, the Partnership shall provide cash to the Company for
such purpose which shall be equal to redemption price of the Series C Preferred
Shares to be redeemed and one Series C Preferred Unit shall be canceled with
respect to each Series C Preferred Share so redeemed. From and after the date in
which the Series C Preferred Shares are redeemed, the Series C Preferred Units
so canceled shall no longer be outstanding and all rights hereunder, to
distributions or otherwise, with respect to such Series C Preferred Units shall
cease.

       3.     Except as modified herein, all terms and conditions of the
Partnership Agreement shall remain in full force and effect, which terms and
conditions the Managing General Partner hereby ratifies and confirms.

       4.     This Amendment is effective as of the date first set forth above.

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       IN WITNESS WHEREOF, the undersigned have executed 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 existing
                                    Limited Partners.

                                    By:   /s/ STANLEY M. STEVENS
                                         --------------------------------------

                                    Name: Stanley M. Stevens
                                         --------------------------------------
                                    Title:  Executive Vice President and Chief
                                            Legal Counsel

                                    ZELL/MERRILL LYNCH REAL ESTATE
                                    OPPORTUNITY PARTNERS LIMITED
                                    PARTNERSHIP II, General Partner

                                    By:  Equity Office Properties Trust, its
                                         managing general partner

                                         By: /s/ STANLEY M. STEVENS
                                            ------------------------------------

                                         Name: Stanley M. Stevens
                                            ------------------------------------

                                         Title: Executive Vice President and
                                                Chief Legal Counsel

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