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                                                                    EXHIBIT 4.3

                      FIRST AMENDMENT TO RIGHTS AGREEMENT


              FIRST AMENDMENT, dated as of October 13, 2000 ("First Amendment"),
to Rights Agreement dated as of August 14, 1998 (the "Rights Agreement"),
between Arden Realty, Inc., a Maryland corporation (the "Company"), and The Bank
of New York (the "Rights Agent"). Capitalized terms used but not otherwise
defined herein shall have the meanings ascribed to them in the Rights Agreement.

              WHEREAS, the Company and the Rights Agent previously entered into
the Rights Agreement; and

              WHEREAS, pursuant to Section 26 of the Rights Agreement, the
Company and the Rights Agent may from time to time supplement or amend any
provision of the Rights Agreement in accordance with the terms of such Section
26.

              NOW, THEREFORE, in consideration of the foregoing premises and
mutual agreements set forth in this Amendment, the parties hereby amend the
Rights Agreement as follows:

              1. Section 1.3(ii)(A)(z) of the Rights Agreement is hereby amended
and restated in its entirety to reads as follows:

              "(z) securities which such Person or any of such Person's
       Affiliates or Associates may acquire, does or do acquire or may be deemed
       to acquire or may be deemed to have the right to acquire, pursuant to any
       merger or other acquisition agreement between the Company and such Person
       (or one or more of such Person's Affiliates or Associates) if prior to
       such Person becoming an Acquiring Person the Board of Directors of the
       Company has approved such agreement and determined that such Person shall
       not be or be deemed to be the beneficial owner of such securities within
       the meaning of this Section 1.3; or."

              2. The following is hereby added as a new Section 1.9 of the
Rights Agreement and former Sections 1.9 through 1.13, respectively, are hereby
renumbered as Sections 1.10 through 1.14 respectively:

              "1.9. `Future Director' shall mean any director who is not a
       Continuing Director."

              3. The last sentence of Section 11.1.3 is hereby amended and
restated to read in its entirety as follows:

              "For a period of 180 days following a Trigger Event, actions by
       the Company pursuant to this Section 11.1.3 shall be approved by the vote
       of a majority of the Continuing Directors, and no Future Director shall
       be entitled to vote with respect to such action. Thereafter, such actions
       shall be approved by the vote of a majority of the Board of Directors."


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              4. The last sentence of Section 11.4.1 of the Rights Agreement is
hereby amended and restated in its entirety to read as follows:

              "If the Security is not publicly held or not so listed or traded,
       or if on any such date the Security is not so quoted and no such market
       maker is making a market in the Security, "current per share market
       price" shall mean the fair value per share as determined in good faith
       (i) by the Board of Directors of the Company if at the time of
       determination there is no Acquiring Person, (ii) if at the time of
       determination there is an Acquiring Person, for a period of 180 days
       following a Trigger Event, by a majority of the Continuing Directors, or
       (iii) if there are no Continuing Directors or if the 180 day period
       following a Trigger Event has expired, by a nationally recognized
       investment banking firm selected by the Board of Directors, which shall
       have the duty to make such determination in a reasonable and objective
       manner, whose determination shall be described in a statement filed with
       the Rights Agent and shall be conclusive for all purposes."

              5. The penultimate sentence of Section 11.4.2 of the Rights
Agreement is hereby amended and restated in its entirety to read as follows:

              "If on any such date neither the Common Shares nor the Preferred
       Shares are so quoted and no such market maker is making a market in
       either the Common Shares or the Preferred Shares, "current per share
       market price" of the Preferred Shares shall mean the fair value per share
       as determined in good faith (i) by the Board of Directors of the Company
       if at the time of determination there is no Acquiring Person, (ii) if at
       the time of determination there is an Acquiring Person, for a period of
       180 days following a Trigger Event, by a majority of the Continuing
       Directors, or (iii) if there are no Continuing Directors or if the 180
       day period following a Trigger Event has expired, by a nationally
       recognized investment banking firm selected by the Board of Directors of
       the Company, which shall have the duty to make such determination in a
       reasonable and objective manner, which determination shall be described
       in a statement filed with the Rights Agent and shall be conclusive for
       all purposes."

              6. Section 13.3 of the Rights Agreement is hereby amended and
restated to read in its entirety as follows:

              "Section 13.3 Approved Acquisitions. Notwithstanding anything
       contained herein to the contrary, upon the consummation of any merger or
       other acquisition transaction of the type described in clause (A), (B) or
       (C) of Section 13.1 involving the Company pursuant to a merger or other
       acquisition agreement between the Company and any Person (or one or more
       of such Person's Affiliates or Associates) which agreement has been
       approved by the Board of Directors of the Company prior to any Person
       becoming an Acquiring Person, this Agreement and the rights of holders of
       Rights hereunder shall be terminated in accordance with Section 7.1."

              7. The last sentence of Section 14.1 of the Rights Agreement is
hereby amended and restated in its entirety to read as follows:


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              "If on any such date no such market maker is making a market in
       the Rights, the current market value of the Rights on such date shall be
       the fair value of the Rights as determined in good faith (i) by the Board
       of Directors of the Company if at the time of determination there is no
       Acquiring Person, (ii) if at the time of determination there is an
       Acquiring Person, for a period of 180 days following a Trigger Event, by
       a majority of the Continuing Directors, or (iii) if there are no
       Continuing Directors or if the 180 day period following a Trigger Event
       has expired, by a nationally recognized investment banking firm selected
       by the Board of Directors of the Company, which shall have the duty to
       make such determination in a reasonable and objective manner, which
       determination shall be described in a statement filed with the Rights
       Agent and shall be conclusive for all purposes."

              8. The second sentence of Section 22 of the Rights Agreement is
hereby amended and restated to read in its entirety as follows:

              "In addition, in connection with the issuance or sale of Common
       Shares following the Distribution Date and prior to the Expiration Date,
       the Company (a) shall, with respect to Common Shares so issued or sold
       pursuant to the exercise of stock options or under any employee plan or
       arrangements, granted or awarded as of the Distribution Date, or upon
       exercise, conversion or exchange of securities hereafter issued by the
       Company, and (b) may, in any other case, if deemed necessary or
       appropriate by the Board of Directors of the Company, issue Right
       Certificates representing the appropriate number of Rights in connection
       with such issuance or sale; PROVIDED, HOWEVER, that (i) no such Right
       Certificate shall be issued if, and to the extent that, the Company shall
       be advised by counsel that such issuance would create a significant risk
       of material adverse tax consequences to the Company or the Person to whom
       such Right Certificate would be issued, (ii) no such Right Certificate
       shall be issued if, and to the extent that, appropriate adjustment shall
       otherwise have been made in lieu of the issuance thereof and (iii) at the
       time of a determination by the Board of Directors to cause the Company to
       issue a Right Certificate under clause (b) above, there must be
       Continuing Directors then in office and any such determination shall
       require the approval of at least a majority of such Continuing Directors;
       provided, however, that this clause (iii) shall be applicable only for
       the 180 day period following a Trigger Event."

              9. The last sentence of Section 26 of the Rights Agreement is
hereby amended and restated to read in its entirety as follows:

              "Any supplement or amendment to this Agreement pursuant to this
       Section 26 shall be approved by a majority of the Board of Directors;
       provided, however, that for a period 180 days following a Trigger Event,
       any supplement or amendment to this Agreement pursuant to this Section 26
       shall be approved by a vote of the majority of the Continuing Directors,
       and no Future Director shall be entitled to vote with respect to such
       supplement or amendment. Thereafter, any such supplement or amendment
       shall be approved by the vote of a majority of the Board of Directors."


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              10. Section 30 of the Rights Agreement is hereby amended and
restated in its entirety as follows:

              "Section 30 Determination and Actions by the Board of Directors.
       The Board of Directors of the Company (in conjunction with the Continuing
       Directors as specifically provided in this Agreement) or, where
       applicable as specifically provided in this Agreement, the Continuing
       Directors, shall have the exclusive power and authority to administer
       this Agreement and to exercise the rights and powers specifically granted
       to the Board of Directors of the Company (in conjunction with the
       Continuing Directors, as applicable) or to the Continuing Directors or to
       the Company, or as may be necessary or advisable in the administration of
       this Agreement, including, without limitation, the right and power to (i)
       interpret the provisions of this Agreement and (ii) make all
       determinations deemed necessary or advisable for the administration of
       this Agreement (including, without limitation, a determination to redeem
       or not redeem the Rights or amend this Agreement). All such actions,
       calculations, interpretations and determinations (including, for purposes
       of clause (y) below, all omissions with respect to the foregoing) that
       are done or made by the Board of Directors of the Company or the
       Continuing Directors, as applicable, in good faith shall (x) be final,
       conclusive and binding on the Company, the Rights Agent, the holders of
       the Rights, as such, and all other parties, and (y) not subject the Board
       of Directors or the Continuing Directors, as applicable, to any liability
       to the holders of the Rights. Notwithstanding any provision in this
       Section 30 or any other provision of this Agreement, (i) any requirement
       that Continuing Directors vote for or approve any action shall be limited
       to the 180 day period following a Trigger Event, and (ii) no Future
       Director shall be entitled to vote for the redemption, modification or
       termination of the Rights for a period of 180 days following a Trigger
       Event."

       11. The fourth paragraph of Exhibit B to the Rights Plan ("Form of Right
Certificate) is hereby amended and restated in its entirety as follows:

              "Subject to the provisions of the Agreement, the Board of
       Directors may, at its option, (i) redeem the Rights represented by this
       Right Certificate at a redemption price of $.01 per Right at any time
       prior to the close of business on the tenth day after the Shares
       Acquisition Date or (ii) exchange Common Shares for the Rights
       represented by this Certificate, in whole or in part. The period during
       which redemption of the Rights is permitted may be extended by the Board
       of Directors of the Company; provided, however, that for a period of 180
       days following a Trigger Event, such an extension shall require the
       concurrence of a majority of the Continuing Directors. Unless otherwise
       provided in the Rights Agreement, no Future Director shall be entitled to
       vote for the redemption, modification or termination of the Rights for a
       period of 180 days following a Trigger Event."

       12. The tenth paragraph of Exhibit C to the Rights Plan (SUMMARY OF
RIGHTS TO PURCHASE PREFERRED SHARES), is hereby amended to (a) delete the words
"close of business on the tenth business day following the first date of public
announcement that


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a Person has become an Acquiring Person" and replace them with the words "time
that an Acquiring Person has become such.

              13. This First Amendment shall be effective as of the date hereof
and, except as expressly set forth herein, the Rights Agreement shall remain in
full force and effect and be otherwise unaffected hereby.

              14. This First Amendment may be executed in any number of
counterparts, each of which, when executed, shall be deemed to be an original
and all such counterparts shall together constitute one and the same document.

              IN WITNESS WHEREOF, the parties have executed this First Amendment
as of the date first written above.



                                        ARDEN REALTY, INC.


                                        By: /s/ DAVID A. SWARTZ
                                            ------------------------------------
                                        Name:  David A. Swartz
                                        Title: Secretary


                                        THE BANK OF NEW YORK


                                        By: /s/ WILLIAM F. POWERS
                                            ------------------------------------
                                        Name:  William F. Powers
                                        Title: Assistant Vice President


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