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                                                                   EXHIBIT 10.23

                     SECOND AMENDMENT TO OPERATING AGREEMENT
                             OF GGP/HOMART II L.L.C.

     Second Amendment to Operating Agreement, dated January 31, 2003 (the
"Amendment"), among GGP Limited Partnership, a Delaware limited partnership
("GGPLP"), The Comptroller of the State of New York as Trustee of the Common
Retirement Fund, a fund established pursuant to NY Retirement and Social
Security Law Section 422, in the custody of the Comptroller of the State of New
York ("NYSCRF" and, together with GGPLP, the "Members"), and GGP/Homart II
L.L.C., a Delaware limited liability company (the "Company").

                                    RECITALS

     WHEREAS, the Members are all of the members of the Company;

     WHEREAS, the Company and the Members entered into that certain Operating
Agreement dated November 10, 1999, as amended (the "Existing Operating
Agreement"), relating to, among other things, the management of the Company and
the transfer of units of membership interest therein; and

     WHEREAS, the parties hereto desire to amend the Existing Operating
Agreement as set forth herein.

     NOW, THEREFORE, for and in consideration of the mutual covenants and
agreements set forth herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties do hereby
agree as follows:

     1. Definitions. Capitalized terms used herein without definition shall have
the meanings set forth in the Existing Operating Agreement.

     2. Amendment to Section 7.2(a). Section 7.2(a) of the Existing Operating
Agreement is hereby deleted in its entirety and the following is hereby inserted
in lieu thereof:

               "7.2. Board.

                    (a) Except as otherwise expressly set forth herein, the
               Board of Directors of the Company shall consist of four (4)
               members, and the holders of Class A Units (by majority vote)
               shall have the right from time to time at their election to
               designate two (2) members to the Board (the "Class A Board
               Members"), and the holders of Class B Units (by majority vote)
               shall have the right from time to time at their election to
               designate two (2) members to the Board (the "Class B Board

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               Members" and, together with the Class A Board Members, the "Board
               Members")."

     3. Amendment to Section 7.7(a). Section 7.7(a) of the Existing Operating
Agreement is hereby deleted in its entirety and the following is hereby inserted
in lieu thereof:

               "7.7 Actions by the Board.

                    (a) Actions by Directors. Except as otherwise provided
               herein, at such times as both Class A Units and Class B Units
               shall be outstanding, at all meetings of the Board a quorum shall
               exist for the transaction of business if at least one (1) Class A
               Board Member and one (1) Class B Board Member are present. At
               such times as both Class A Units and Class B Units shall be
               outstanding, at all meetings of any committee of the Board a
               quorum shall exist for the transaction of business if at least
               one member designated by the Class A Board Members and one member
               designated by the Class B Board Members are present, unless the
               Board shall determine otherwise. At all other times (i.e., when
               the Board is constituted pursuant to Section 8.4(c)), a quorum
               shall exist for the transaction of business if at least a
               majority of Board or committee members are present. Actions of
               the Board or any committee thereof may be taken at meetings or by
               written consent, and any written consent shall be filed with the
               minutes of proceedings of the Board or the appropriate committee
               thereof. Attendance at any meeting may be by conference telephone
               or similar communications equipment by means of which all persons
               participating in the meeting can hear each other. In case at any
               meeting of the Board or a committee thereof a quorum shall not be
               present, the members of the Board or such committee present may
               adjourn the meeting from time to time until a quorum shall be
               present."

     4. Counterparts. This Amendment may be executed in counterparts, each of
which shall constitute an original and all which together shall constitute the
same agreement.

     5. Captions. The article and section headings appearing in this Amendment
are for convenience of reference only and are not intended, to any extent and
for any purpose, to limit or define the text of any section or any subsection
hereof.

     6. Full Force and Effect; Etc. Except as expressly set forth herein, this
Amendment does not constitute a waiver or modification of any provision of the
Existing Operating Agreement. Except as expressly amended hereby, the Existing
Operating


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Agreement shall continue in full force and effect in accordance with the
provisions thereof on the date hereof. As used in the Existing Operating
Agreement (including without limitation the Exhibits and Schedules thereto), the
terms "the Agreement," "herein," "hereof," "hereinafter," "hereto" and words of
similar import, shall, unless the context otherwise requires, mean the Existing
Operating Agreement, as amended by this Amendment. Notwithstanding anything to
the contrary contained in the Existing Operating Agreement, the matters
contained herein shall not require Board approval.

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     IN WITNESS WHEREOF, the parties hereto have duly executed this Amendment on
the date first written above.

                                        GGP LIMITED PARTNERSHIP, a Delaware
                                        limited partnership

                                        By: General Growth Properties, Inc., a
                                            Delaware corporation, its general
                                            partner


                                        By: /s/ Robert A. Michaels
                                            ------------------------------------
                                        Name: Robert A. Michaels
                                        Title: President


                                        COMPTROLLER OF THE STATE OF NEW YORK, as
                                        trustee of the Common Retirement Fund


                                        By: /s/ Jacques Jiha
                                            ------------------------------------
                                        Name: Jacques Jiha
                                        Title: Deputy Comptroller for
                                               Investments and Cash Management


                                        GGP/HOMART II L.L.C., a Delaware limited
                                        liability company


                                        By: /s/ Robert A. Michaels
                                            ------------------------------------
                                        Name: Robert A. Michaels
                                        Title: President


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