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                                                                   EXHIBIT 3.6.2

                        AMENDMENT NO. 3 TO THE BYLAWS OF
                         EQUITY OFFICE PROPERTIES TRUST
                             EFFECTIVE JULY 14, 1999


       This will confirm that, effective as of July 14, 1999, the Bylaws of
Equity Office Properties Trust have been amended in order to add Section 11 as
follows:

       SECTION 11. COMMITTEE ON TRUST GOVERNANCE. The Committee on Trust
Governance shall be composed of not less than three Trustees. The Committee on
Trust Governance shall be authorized to (i) study, and review with management,
the overall effectiveness of the organization of the Board of Trustees and the
conduct of its business, and make appropriate recommendations to the Trustees
with regard thereto; (ii) review the appropriateness and adequacy of information
supplied to the Trustees prior to and during Board of Trustee meetings of the
Trustees; (iii) develop, submit to the Trustees for their approval and
thereafter monitor implementation of Guidelines on Trust Governance Issues in
respect to the operation of the Board of Trustees and propose to the Trustees
for their approval from time to time such revisions therein as the Committee on
Trust Governance deems to be appropriate; (iv) develop and maintain criteria and
procedures for the identification and recruitment or retention of candidates for
election or reelection to serve as Trustees of the Trust, including
consideration of the performance of incumbent Trustees in determining whether to
nominate them for reelection; and (v) recommend to the Trustees, with the advice
of the Chairman and the President and Chief Executive Officer of the Trust,
nominees for election or reelection as Trustees. The Chairman of the Board as
well as the President and Chief Executive Officer shall be ex-officio members of
the Committee on Trust Governance.


                             /s/ STANLEY M. STEVENS
                        --------------------------------
                                    Secretary





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                        AMENDMENT NO. 4 TO THE BYLAWS OF
                         EQUITY OFFICE PROPERTIES TRUST
                          EFFECTIVE SEPTEMBER 27, 1999

       This will confirm that, effective as of September 27, 1999, Sections 8.2
and 8.3 of the Bylaws of Equity Office Properties Trust have been amended and
restated in its entirety as follows:

       8.2    The Special Conflicts Committee shall have the power to consider
and, in each case where the transaction obligates or is expected to obligate the
Trust in an amount not greater than Fifty Million Dollars ($50,000,000), to
approve any transaction in which the Trust is or is proposed to be a party and
as to which any Trustee knows at the time of commitment that any of the
following persons either is or is entitled to be a party, whether directly or
indirectly, to the transaction or has a sufficiently material beneficial
interest that the interest might reasonably be expected to exert an influence on
the Trustee's judgment if he were called upon to vote on the transaction: (a)
any Trustee or any Related Person of any Trustee; (b) any person (other than the
Trust) of which the Trustee is the owner of more than 5% of any class of equity
securities or is a director, trustee, general partner, agent or employee; (c)
any person that controls one or more of the persons specified in clause (b) or a
person that is controlled by, or is under common control with, one or more of
the persons specified in clause (b); or (d) an individual who is a general
partner, principal or employer of the Trustee.

       8.3    Any Trustee who knows of a transaction covered by Section 8.2
shall immediately notify and provide all material information about the
transaction to the Special Conflicts Committee, which shall thereafter promptly
consider the transaction. The Board of Trustees, any Trustee or any officer of
the Trust may notify the Special Conflicts Committee about any transaction that
it has reason to believe is covered by Section 8.2 and, upon request, such
Trustee shall provide to the Special Conflicts Committee all relevant
information known or in the control of the referring person. Upon receipt of
notice pursuant to this paragraph, the Special Conflicts Committee shall notify
the Chairman of the Board and the Secretary of the Trust in order that the Board
of Trustees which, absent the Board's determination that such notice was
improper, shall take no further action with respect to the transaction unless
and until approved, ratified or recommended to the Board by the Special
Conflicts Committee. The Trust shall not enter into such transaction without the
approval, ratification or recommendation of the Special Conflicts Committee
acting by unanimous written consent or by the affirmative vote of a majority of
its members present and voting at any meeting thereof (excluding any members
disqualified pursuant to Section 8.4). Nothing in this Section 8 shall require
approval of fees or other compensation to Independent Trustees for their service
as Trustees.

                                               /s/ STANLEY M. STEVENS
                                          --------------------------------
                                                  Secretary