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                                                                     EXHIBIT 3.6


                           CERTIFICATE OF AMENDMENT OF
                                  THE BYLAWS OF
                               ARDEN REALTY, INC.


                     The undersigned does hereby certify that:

                      1. He is the duly elected Secretary of Arden Realty, Inc.,
a Maryland corporation (the "Corporation"); and

                      2. By resolutions duly adopted by written consent of the
Corporation's Board of Directors dated March 17, 2000, Section 1, Section 3,
Section 9, Section 12(a)(2), 12(a)(3) and Section 12(b) of Article II as well as
Section 5 and Section 10 of Article III of the Corporation's Bylaws were amended
as follows:

                                   ARTICLE II

           Section 1. PLACE. All meeting of stockholders shall be held at the
           principal office of the Corporation or at such other place as shall
           be stated in the notice of the meeting.

           Section 3.  SPECIAL MEETINGS.

                     (a) General. The president, chief executive officer or
           Board of Directors may call special meetings of the stockholders.
           Subject to subsection (b) of this Section 3, special meetings of
           stockholders shall also be called by the secretary of the Corporation
           upon the written request of the holders of shares entitled to cast
           not less than a majority of all the votes entitled to be cast at such
           meeting.

                     (b) Stockholder Requested Special Meetings. (1) Any
           stockholder of record seeking to have stockholders request a special
           meeting shall, by sending written notice to the secretary (the
           "Record Date Request Notice") by registered mail, return receipt
           requested, request the Board of Directors to fix a record date to
           determine the stockholders entitled to request a special meeting (the
           "Request Record Date"). The Record Date Request Notice shall set
           forth the purpose of the meeting and the matters proposed to be acted
           on at it, shall be signed by one or more stockholders of record as of
           the date of signature (or their duly authorized proxies or other
           agents), shall bear the date of signature of each such stockholder
           (or proxy or other agent) and shall set forth all information
           relating to each such stockholder that must be disclosed in
           solicitations of proxies for election of directors in an election
           contest (even if an election contest is not involved), or is
           otherwise required, in each case pursuant to Regulation 14A under the
           Securities Exchange Act of 1934, as amended (the "Exchange Act"), and
           Rule 14a-11 thereunder. Upon receiving the Record Date Request
           Notice, the Board of Directors may fix a Request Record Date. The
           Request Record Date shall not precede and shall not be more than ten
           days after the close of business on the date on which the resolution
           fixing

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           the Request Record Date is adopted by the Board of Directors. If the
           Board of Directors, within ten days after the date on which a valid
           Record Date Request Notice is received, fails to adopt a resolution
           fixing the Request Record Date and make a public announcement of such
           Request Record Date, the Request Record Date shall be the close of
           business on the tenth day after the first date on which the Record
           Date Request Notice is received by the secretary.

                               (2) In order for any stockholder to request a
                     special meeting, one or more written requests for a special
                     meeting signed by stockholders of record (or their duly
                     authorized proxies or other agents) as of the Request
                     Record Date entitled to cast not less than a majority (the
                     "Special Meeting Percentage") of all of the votes entitled
                     to be cast at such meeting (the "Special Meeting Request")
                     shall be delivered to the secretary. In addition, the
                     Special Meeting Request shall set forth the purpose of the
                     meeting and the matters proposed to be acted on at it
                     (which shall be limited to the matters set forth in the
                     Record Date Request Notice received by the secretary),
                     shall bear the date of signature of each such stockholder
                     (or proxy or other agent) signing the Special Meeting
                     Request, shall set forth the name and address, as they
                     appear in the Corporation's books, of each stockholder
                     signing such request (or on whose behalf the Special
                     Meeting Request is signed) and the class and number of
                     shares of stock of the Corporation which are owned of
                     record and beneficially by each such stockholder, shall be
                     sent to the secretary by registered mail, return receipt
                     requested, and shall be received by the secretary within 60
                     days after the Request Record Date. Any requesting
                     stockholder may revoke his, her or its request for a
                     special meeting at any time by written revocation delivered
                     to the secretary.

                               (3) The secretary shall inform the requesting
                     stockholders of the reasonably estimated cost of preparing
                     and mailing the notice of meeting (including the
                     Corporation's proxy materials). The secretary shall not be
                     required to call a special meeting upon stockholder request
                     and such meeting shall not be held unless, in addition to
                     the documents required by paragraph (2) of this Section
                     3(b), the secretary receives payment of such reasonably
                     estimated cost prior to the mailing of any notice of the
                     meeting.

                               (4) Except as provided in the next sentence, any
                     special meeting shall be held at such place, date and time
                     as may be designated by the president, chief executive
                     officer or Board of Directors, whoever has called the
                     meeting. In the case of any special meeting called by the
                     secretary upon the request of stockholders (a "Stockholder
                     Requested Meeting"), such meeting shall be held at such
                     place, date and time as may be designated by the Board of
                     Directors; provided, however, that the date of any
                     Stockholder Requested Meeting shall be not more than 90
                     days after the record date for such meeting (the "Meeting
                     Record Date"); and provided further that if the Board of
                     Directors fails to designate, within ten days after the
                     date that a valid Special Meeting Request is actually
                     received by the secretary (the "Delivery Date"), a date and
                     time for a Stockholder Requested Meeting, then such meeting
                     shall be held at 2:00 p.m. local time on the 90th day after
                     the Meeting Record Date or, if such 90th day is not

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                     a Business Day (as defined below), on the first preceding
                     Business Day; and provided further that in the event that
                     the Board of Directors fails to designate a place for a
                     Stockholder Requested Meeting within ten days after the
                     Delivery Date, then such meeting shall be held at the
                     principal executive offices of the Corporation. In fixing a
                     date for any special meeting, the president, chief
                     executive officer or Board of Directors may consider such
                     factors as he, she or it deems relevant within the good
                     faith exercise of business judgment, including, without
                     limitation, the nature of the matters to be considered, the
                     facts and circumstances surrounding any request for meeting
                     and any plan of the Board of Directors to call an annual
                     meeting or a special meeting. In the case of any
                     Stockholder Requested Meeting, if the Board of Directors
                     fails to fix a Meeting Record Date that is a date within 30
                     days after the Delivery Date, then the close of business on
                     the 30th day after the Delivery Date shall be the Meeting
                     Record Date.

                               (5) If at any time as a result of written
                     revocations of requests for the special meeting,
                     stockholders of record (or their duly authorized proxies or
                     other agents) as of the Request Record Date entitled to
                     cast less than the Special Meeting Percentage shall have
                     delivered and not revoked requests for a special meeting,
                     the secretary may refrain from mailing the notice of the
                     meeting or, if the notice of the meeting has been mailed,
                     the secretary may revoke the notice of the meeting at any
                     time before ten days before the meeting if the secretary
                     has first sent to all other requesting stockholders written
                     notice of such revocation and of intention to revoke the
                     notice of the meeting. Any request for a special meeting
                     received after a revocation by the secretary of a notice of
                     a meeting shall be considered a request for a new special
                     meeting.

                               (6) The chief executive officer, the president or
                     the Board of Directors may appoint regionally or nationally
                     recognized independent inspectors of elections to act as
                     the agent of the Corporation for the purpose of promptly
                     performing a ministerial review of the validity of any
                     purported Special Meeting Request received by the
                     secretary. For the purpose of permitting the inspectors to
                     perform such review, no such purported request shall be
                     deemed to have been delivered to the secretary until the
                     earlier of (i) five Business Days after receipt by the
                     secretary of such purported request and (ii) such date as
                     the independent inspectors certify to the Corporation that
                     the valid requests received by the secretary represent at
                     least a majority of the issued and outstanding shares of
                     stock that would be entitled to vote at such meeting.
                     Nothing contained in this paragraph (6) shall in any way be
                     construed to suggest or imply that the Corporation or any
                     stockholder shall not be entitled to contest the validity
                     of any request, whether during or after such five Business
                     Day period, or to take any other action (including, without
                     limitation, the commencement, prosecution or defense of any
                     litigation with respect thereto, and the seeking of
                     injunctive relief in such litigation).

                               (7) For purposes of these Bylaws, "Business Day"
                     shall mean any day other than a Saturday, a Sunday or a day
                     on which banking institutions in the State of California
                     are authorized or obligated by law or executive order to
                     close.
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           Section 9. PROXIES. A stockholder may vote the stock owned of record
           by him, either in person or by proxy executed in any manner
           authorized by Maryland law by the stockholder or by his duly
           authorized agent. Such proxy shall be filed with the secretary of the
           Corporation before or at the time of the meeting. No proxy shall be
           valid after eleven months from the date of its execution, unless
           otherwise provided in the proxy.

           Section 12.  NOMINATIONS AND STOCKHOLDER BUSINESS.

                     (a)       Annual Meetings of Stockholders.

                         (2) For nominations or other business to be properly
                     brought before an annual meeting by a stockholder pursuant
                     to clause (iii) of paragraph (a)(1) of this Section 12, the
                     stockholder must have given timely notice thereof in
                     writing to the secretary of the Corporation. To be timely,
                     a stockholder's notice shall be delivered to the secretary
                     at the principal executive offices of the Corporation not
                     less than 90 days nor more than 120 days prior to the first
                     anniversary of the mailing of the notice of the preceding
                     year's annual meeting; provided, however, that in the event
                     that the date of the mailing of the notice of the annual
                     meeting is advanced or delayed by more than 30 days from
                     the anniversary of the date of mailing of the notice of the
                     preceding year's annual meeting, notice by the stockholder
                     to be timely must be so delivered not earlier than the
                     120th day prior to the date of the mailing of the notice of
                     such annual meeting and not later than the close of
                     business on the later of the 90th day prior to the date of
                     the mailing of the notice of such annual meeting or the
                     tenth day following the day on which public announcement of
                     the date of such meeting is first made. Such stockholder's
                     notice shall set forth (i) as to each person whom the
                     stockholder proposes to nominate for election or reelection
                     as a director all information relating to such person that
                     is required to be disclosed in solicitations of proxies for
                     election of directors, or is otherwise required, in each
                     case pursuant to Regulation 14A under the Securities
                     Exchange Act of 1934, as amended (the "Exchange Act")
                     (including such person's written consent to being named in
                     the proxy statement as a nominee and to serving as a
                     director if elected); (ii) as to any other business that
                     the stockholder proposes to bring before the meeting, a
                     brief description of the business desired to be brought
                     before the meeting, the reasons for conducting such
                     business at the meeting and any material interest in such
                     business of such stockholder and of the beneficial owner,
                     if any, on whose behalf the proposal is made; and (iii) as
                     to the stockholder giving the notice and the beneficial
                     owner, if any, on whose behalf the nomination or proposal
                     is made, (x) the name and address of such stockholder, as
                     they appear on the Corporation's books, and of such
                     beneficial owner and (y) the number of shares of each class
                     of stock of the Corporation which are owned beneficially
                     and of record by such stockholder and such beneficial
                     owner.

                         (3) Notwithstanding anything in the second sentence of
                     paragraph (a)(2) of this Section 12 to the contrary, in the
                     event that the number of directors to be elected to the
                     Board of Directors is increased and there is no public
                     announcement naming all of the nominees for director or
                     specifying the size of the increased Board of Directors
                     made by the Corporation at least 100 days prior to the
                     first anniversary of

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                     the mailing of the notice of the preceding year's annual
                     meeting, a stockholder's notice required by this Section
                     12(a) shall also be considered timely, but only with
                     respect to nominees for any new positions created by such
                     increase, if it shall be delivered to the secretary at the
                     principal executive offices of the Corporation not later
                     than the close of business on the tenth day following the
                     day on which such public announcement is first made by the
                     Corporation.

                     (b) Special Meetings of Stockholders. Only such business
           shall be conducted at a special meeting of stockholders as shall have
           been brought before the meeting pursuant to the Corporation's notice
           of meeting. Nominations of persons for election to the Board of
           Directors may be made at a special meeting of stockholders at which
           directors are to be elected (i) pursuant to the Corporation's notice
           of meeting, (ii) by or at the direction of the Board of Directors or
           (iii) provided that the Board of Directors has determined that
           directors shall be elected at such special meeting, by any
           stockholder of the Corporation who is a stockholder of record at the
           time of giving of notice provided for in this Section 12(b), who is
           entitled to vote at the meeting and who complied with the notice
           procedures set forth in this Section 12(b). In the event the
           Corporation calls a special meeting of stockholders for the purpose
           of electing one or more directors to the Board of Directors, any such
           stockholder may nominate a person or persons (as the case may be) for
           election to such position as specified in the Corporation's notice of
           meeting, if the stockholder's notice containing the information
           required by paragraph (a)(2) of this Section 12 shall be delivered to
           the secretary at the principal executive offices of the Corporation
           not earlier than the 120th day prior to such special meeting and not
           later than the close of business on the later of the 90th day prior
           to such special meeting or the tenth day following the day on which
           public announcement is first made of the date of the special meeting
           and of the nominees proposed by the Board of Directors to be elected
           at such meeting.

                                   ARTICLE III

           Section 5. NOTICE. Notice of any special meeting of the Board of
           Directors shall be delivered personally or by telephone, facsimile
           transmission, electronic mail, United States mail or courier to each
           director at his business or residence address. Notice by personal
           delivery, telephone, electronic mail or a facsimile transmission
           shall be given at least two days prior to the meeting. Notice by mail
           shall be given at least five days prior to the meeting and shall be
           deemed to be given when deposited in the United States mail properly
           addressed, with postage thereon prepaid. Telephone notice shall be
           deemed to be given when the director is personally given such notice
           in a telephone call to which he is a party. Electronic mail notice
           shall be deemed to be given when such notice is sent to the director
           at his electronic mail address as it appears on the records of the
           Corporation. Facsimile transmission notice shall be deemed to be
           given upon completion of the transmission of the message to the
           number given to the Corporation by the director and receipt of a
           completed answer-back indicating receipt. Neither the business to be
           transacted at, nor the purpose of, any annual, regular or special
           meeting of the Board of Directors need be stated in the notice,
           unless specifically required by statute or these Bylaws.

           Section 10. VACANCIES. If for any reason any or all the directors
           cease to be directors, such event shall not terminate the Corporation
           or affect these Bylaws or the powers of the

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           remaining directors hereunder (even if fewer than five directors
           remain). Any vacancy on the Board of Directors for any cause may be
           filled at any regular meeting or at any special meeting called for
           that purpose by a majority vote of the remaining directors, although
           such majority may be less than a quorum. Any individual so elected as
           director shall serve until the next annual meeting of stockholders
           and until his successor is elected and qualifies. Any individual
           elected as a director by stockholders shall serve for the balance of
           the term to which he is elected and qualifies.

                     IN WITNESS WHEREOF, I have hereunto subscribed my name as
of this 17th day of March, 2000.


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


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