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                                                                   EXHIBIT 10.12

                              AMB PROPERTY II, L.P.
                               SECOND AMENDMENT TO
                           TENTH AMENDED AND RESTATED
                        AGREEMENT OF LIMITED PARTNERSHIP

           This Second Amendment (this "Amendment") is made as of February 25,
2002, by AMB PROPERTY HOLDING CORPORATION, a Maryland corporation, as general
partner (the "General Partner") of AMB PROPERTY II, L.P., a Delaware limited
partnership (the "Partnership"), and as attorney-in fact for each of the limited
partners of the Partnership (collectively, the "Limited Partners") for the
purpose of amending the Tenth Amended and Restated Agreement of Limited
Partnership of the Partnership dated as of December 6, 2001, as amended by the
First Amendment to Tenth Amended and Restated Agreement of Limited Partnership
dated as of January 1, 2002 (as amended, the "Partnership Agreement"). All
defined terms used herein but not defined herein have the meanings assigned to
them in the Partnership Agreement.

                     WHEREAS, pursuant to Section 7.3D(iv) of the Partnership
Agreement, the General Partner may, without the consent of the other partners,
amend the Partnership Agreement to reflect a change that is of an
inconsequential nature and does not adversely affect the Limited Partners in any
material respect, or to cure any ambiguity in, correct or supplement any
provision;

                     WHEREAS, pursuant to the authority granted under the
Partnership Agreement, the General Partner desires to amend the Partnership
Agreement to correct a typographical error with respect to the date after which
the Series G Preferred Units may be redeemed.

           NOW THEREFORE, pursuant to Section 7.3D of the Partnership Agreement,
the General Partner, on its own behalf and as attorney-in-fact for the Limited
Partners, hereby amends the Partnership Agreement as follows:

           SECTION 1. Amendment to Section 20.5.A of the Partnership Agreement.

                     The first sentence of Section 20.5.A of the Partnership
Agreement is deleted in its entirety and replaced with the following:

                     "The Series G Preferred Units may not be redeemed prior to
August 29, 2005."

           SECTION 2. Miscellaneous.

                     2.1 Governing Law. This Amendment shall be construed under
and governed by the internal laws of the State of Delaware without regard to its
conflict of laws provisions.

           SECTION 3. Partnership Agreement. The Partnership Agreement and this
Amendment shall be read together and shall have the same effect as if the
provisions of the Partnership Agreement and this Amendment were contained in one
document. Any provisions of the Partnership Agreement not amended by this
Amendment shall remain in full force and effect as provided in the Partnership
Agreement immediately prior to the date hereof.




                                       1
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        IN WITNESS WHEREOF the parties hereto have caused this Amendment to be
executed as of the date set forth above by their duly authorized
representatives.

                              GENERAL PARTNER:

                              AMB PROPERTY HOLDING CORPORATION,
                              a Maryland corporation



                              By:  /s/ Michael A. Coke
                                 -----------------------------------------------
                                   Michael A. Coke
                                   Executive Vice President and Chief Financial
                                   Officer


                              COMMON LIMITED PARTNER:

                              AMB PROPERTY, L.P., a Delaware limited partnership


                              By:  AMB Property Corporation,
                                   its general partner


                              By:  /s/ Michael A. Coke
                                 -----------------------------------------------
                                   Michael A. Coke
                                   Executive Vice President and Chief Financial
                                   Officer



                              GENERAL PARTNER OF COMMON LIMITED PARTNER:

                              AMB PROPERTY CORPORATION,
                              a Maryland corporation

                              By:  /s/ Michael A. Coke
                                 -----------------------------------------------
                                   Michael A. Coke
                                   Executive Vice President and Chief Financial
                                   Officer




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                              LIMITED PARTNERS:

                              By:  AMB PROPERTY HOLDING CORPORATION,
                                   a Maryland corporation, as attorney-in-fact
                                   for each of the Limited Partners

                              By:  /s/ Michael A. Coke
                                 -----------------------------------------------
                                   Michael A. Coke
                                   Executive Vice President and Chief Financial
                                   Officer