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                                                                     Exhibit 4.3

                             FORM OF EXCHANGE NOTE

                        ARDEN REALTY LIMITED PARTNERSHIP

                           9.150% Senior Note due 2010

No. 001                                                              $50,000,000
CUSIP No. 03979GAF2

UNLESS THIS NOTE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY
TRUST COMPANY, A NEW YORK CORPORATION ("DTC") (55 WATER STREET, NEW YORK, NEW
YORK) TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR
PAYMENT, AND SUCH NOTE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO., OR SUCH
OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC, AND ANY PAYMENT
IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED
REPRESENTATIVE OF DTC, ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER
HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

UNLESS AND UNTIL THIS NOTE IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN
CERTIFICATED FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY DTC TO
A NOMINEE THEREOF OR BY A NOMINEE THEREOF TO DTC OR ANOTHER NOMINEE OF DTC OR BY
DTC OR ANY SUCH NOMINEE TO A SUCCESSOR OF DTC OR A NOMINEE OF SUCH SUCCESSOR.

THE HOLDER OF THIS SECURITY BY ITS ACCEPTANCE HEREOF AGREES TO BE BOUND BY THE
PROVISIONS OF THE REGISTRATION RIGHTS AGREEMENT DATED AS OF MARCH 17, 2000,
BETWEEN ARDEN REALTY LIMITED PARTNERSHIP AND THE INITIAL PURCHASERS RELATING TO
THE NOTE.



               ARDEN REALTY LIMITED PARTNERSHIP, a Maryland limited partnership
(herein referred to as the "Issuer," which term includes any successor issuer
under the Indenture hereinafter referred to), for value received, hereby
promises to pay to Cede & Co., or registered assigns, the principal sum of Fifty
Million Dollars on March 1, 2010 (the "Stated Maturity Date") or the date fixed
for earlier redemption (the "Redemption Date," and together with the Stated
Maturity Date with respect to principal repayable on such date, the "Maturity
Date"), and to pay interest thereon from March 17, 2000, or from the most recent
Interest Payment Date to which interest has been paid or duly provided for,
semi-annually in arrears on March 1 and September 1 of each year (each, an
"Interest Payment Date"), commencing September 1, 2000, and on the Maturity Date
at the rate of 9.150% per annum, until the principal hereof is paid or duly
provided for.

               The interest so payable, and punctually paid or duly provided
for, on any Interest Payment Date and on the Maturity Date will, as provided in
such Indenture, be paid to the



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Holder in whose name this Note (or one or more Predecessor Securities) is
registered at the close of business on the Regular Record Date for such payment,
which shall be the date 15 calendar days (regardless of whether such day is a
Business Day), next preceding such Interest Payment Date or the Maturity Date at
the office or agency of the Issuer maintained for such purpose. Any such
interest not so punctually paid or duly provided for shall forthwith cease to be
payable to the Holder on such Regular Record Date, and may be paid to the Holder
in whose name this Note (or one or more Predecessor Securities) is registered at
the close of business on a Special Record Date for the payment of such Defaulted
Interest to be fixed by the Trustee hereinafter referred to, notice whereof
shall be given to Holders of Notes of this series not less than 10 days prior to
such Special Record Date, or may be paid at any time in any other lawful manner
not inconsistent with the requirements of any securities exchange on which the
Notes of this series may be listed, and upon such notice as may be required by
such exchange, all as more fully provided in the Indenture. Interest on this
Note will be computed on the basis of a 360-day year of twelve 30-day months.

               The principal of this Note payable on the Maturity Date will be
paid against presentation and surrender of this Note at the Corporate Trust
Office of the Trustee maintained for that purpose in the Borough of Manhattan,
the City of New York, in such coin or currency of the United States of America
as at the time of payment is legal tender for the payment of public and private
debts.

               Interest payable on this Note on any Interest Payment Date and on
the Maturity Date, as the case may be, will be the amount of interest accrued
during the applicable Interest Period (as defined below).

               An "Interest Period" is each period from and including the
immediately preceding Interest Payment Date in respect of which interest has
been paid or duly provided for (or from and including March 17, 2000, if no
interest has been paid on this Note) to but excluding such Interest Payment Date
or the Maturity Date, as the case may be. If any Interest Payment Date or
Maturity Date falls on a day that is not a Business Day, as defined below,
principal and interest payable with respect to such Interest Payment Date or
Maturity Date, as the case may be, will be paid on the next succeeding Business
Day with the same force and effect as if it were paid on the date such payment
was due, and no interest shall accrue on the amount so payable for the period
from and after such Interest Payment Date or Maturity Date, as the case may be.
"Business Day" means any day, other than a Saturday or Sunday that is neither a
legal holiday nor a day on which banking institutions in the City of New York
are authorized or required by law, regulation or executive order to close.

               Payments of principal and interest in respect of this Note will
be made by U.S. dollar check or by wire transfer (such a wire transfer to be
made only to a Holder of an aggregate principal amount of Securities in excess
of $5,000,000, and only if such Holder shall have furnished wire instructions in
writing to the Trustee no later than 15 days prior to the relevant payment date
and acknowledged that a wire transfer fee shall be payable) of immediately
available funds in such coin or currency of the United States of America as at
the time of payment is legal tender for the payment of public and private debts.


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               The Holder of this Security is entitled to the benefits of and is
subject to the obligations contained in a Registration Rights Agreement (subject
to the provisions thereof), dated as of March 17, 2000, between the Issuer and
the Initial Purchasers (the "Registration Rights Agreement").

               This Note is one of a duly authorized issue of debentures, notes,
bonds or other evidences of indebtedness of the Issuer (herein called the
"Securities") of the series hereafter specified, all issued or to be issued
under an Indenture, dated as of March 14, 2000 (herein called the "Indenture"),
duly executed and delivered by the Issuer to The Bank of New York, as Trustee
(herein called the "Trustee," which term includes any successor trustee under
the Indenture with respect to the series of Securities of which this Note is a
part), to which Indenture and all indentures supplemental thereto reference is
hereby made for a statement of the rights, limitations of rights, obligations,
duties and immunities thereunder of the Issuer, the Trustee and the Holders of
the Securities, and of the terms upon which the Securities are, and are to be,
authenticated and delivered. The Securities may be issued in one or more series,
which different series may be issued in various aggregate principal amounts, may
mature at different times, may bear interest (if any) at different rates, may be
subject to different redemption provisions (if any), and may otherwise vary as
provided in the Indenture. This Note is one of a series of Securities designated
as the 9.150% Senior Notes due 2010 (the "Notes"), and the aggregate principal
amount of the Notes to be issued under such series is unlimited.

               In case an Event of Default with respect to the Notes shall have
occurred and be continuing, the principal hereof and the Make-Whole Amount (if
any) may be declared, and upon such declaration shall become, due and payable,
in the manner, with the effect, and subject to the conditions provided in the
Indenture.

               The Issuer may redeem the Securities at any time, in whole or in
part, at the election of the Issuer, at a redemption price equal to the sum of
(1) the principal amount of the Securities being redeemed plus accrued interest
thereon to the Redemption Date, and (2) the Make-Whole Amount, if any, with
respect to such Securities (the "Redemption Price"). Notice of optional
redemption of any Securities will be given to Holders at their addresses, as
shown in the security register for the Notes, not less than 30 nor more than 60
days prior to the Redemption Date. The notice of redemption will specify, among
other items, the Redemption Price and the principal amount of the Securities
held by such Holder to be redeemed. If less than all the Notes are to be
redeemed at the option of the Issuer, the Issuer will notify the Trustee at
least 45 days prior to giving notice of redemption to the Holders (or such
shorter period as is satisfactory to the Trustee) of the aggregate principal
amount of Notes to be redeemed and their redemption date. The Trustee shall
select, in such manner as it shall deem fair and appropriate, Notes to be
redeemed in whole or in part.

               Subject to certain limitations in the Indenture, at any time when
the Issuer is not subject to Section 13 or 15(d) of the United States Securities
Exchange Act of 1934, as amended, upon the request of a Holder of a Restricted
Security (as defined in the Registration Rights Agreement) the Issuer will
promptly furnish or cause to be furnished Rule 144A Information (as defined in
the Registration Rights Agreement) to such Holder of Restricted Securities, or
to a prospective purchaser of any security designated by any such Holder to the
extent required to


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permit compliance by such Holder with Rule 144A under the Securities Act in
connection with the resale of any such security.

               In the event of redemption of this Note in part only, a new Note
or Notes for the unredeemed portion hereof shall be issued in the name of the
Holder hereof upon the cancellation hereof.

               The Indenture contains provisions permitting the Issuer and the
Trustee, with the consent of the Holders of not less than a majority of the
aggregate principal amount of the Securities at the time Outstanding of each
series to be affected, evidenced as provided in the Indenture, to execute
supplemental Indentures adding any provisions to or changing in any manner or
eliminating any of the provisions of the Indenture or of any supplemental
Indenture or modifying in any manner the rights of the Holders of the Securities
of each series; provided, however, that no such supplemental Indenture shall,
without the consent of the Holder of each Security so affected, (i) change the
final maturity of any Security, or reduce the principal amount thereof or any
premium thereon, or reduce the rate or extend the time of payment of any
interest thereon, or impair or affect the rights of any Holder to institute suit
for the payment on any Security, or (ii) reduce the aforesaid percentage of
Securities, the Holders of which are required to consent to any such
supplemental Indenture, or (iii) reduce the percentage of Securities, the
Holders of which are required to consent to any waiver of compliance with
certain provisions of the Indenture or any waiver of certain defaults
thereunder. It is also provided in the Indenture that, with respect to certain
defaults or Events of Default regarding the Securities of any series, the
Holders of a majority in aggregate principal amount outstanding of the
Securities of such series (or, in the case of certain defaults or Events of
Default, all series of Securities) may on behalf of the Holders of all the
Securities of such series (or all of the Securities, as the case may be) waive
any such past default or Event of Default and its consequences, prior to any
declaration accelerating the maturity of such Securities, or, subject to certain
conditions, may rescind a declaration of acceleration and its consequences with
respect to such Securities. The preceding sentence shall not, however, apply to
a default in the payment of the principal of or premium, if any, or interest on
any of the Securities. Any such consent or waiver by the Holder of this Security
(unless revoked as provided in the Indenture) shall be conclusive and binding
upon such Holder and upon all future Holders and owners of this Security and any
securities that may be issued in exchange or substitution hereof, irrespective
of whether or not any notation thereof is made upon this Security or such other
securities.

               No reference herein to the Indenture and no provision of this
Note or of the Indenture shall alter or impair the obligation of the Issuer,
which is absolute and unconditional, to pay the principal of and any Make-Whole
Amount and interest on this Note in the manner, at the respective times, places
and rate, and in the coin or currency, herein prescribed.

               As provided in and subject to the provisions of the Indenture,
the Holder of this Security shall not have the right to institute any proceeding
with respect to the Indenture or for the appointment of a receiver or trustee or
for any other remedy thereunder unless (a) such Holder shall have previously
given the Trustee written notice of a continuing Event of Default, (b) the
Holders of not less than 25% in aggregate principal amount of the Securities
Outstanding shall have made written request to the Trustee to institute
proceedings in respect of such Event of Default as Trustee and offered the
Trustee reasonable indemnity and the Trustee shall not have


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received from the Holders of a majority in aggregate principal amount of the
Securities Outstanding a direction inconsistent with such request, and (c) the
Trustee shall have failed to institute any such proceeding, for 60 days after
receipt of such notice, request and offer of indemnity. The foregoing shall not
apply to any suit instituted by the Holder of this Security for the enforcement
of any payment of principal hereof, Make-Whole Amount, if any, or interest
hereon on or after the respective due dates expressed herein.

               This Security is not subject to a sinking fund requirement.

               The Indenture contains provisions for defeasance at any time of
(i) the entire indebtedness of this Security (ii) certain restrictive covenants
with respect to this Security, in each case upon compliance with certain
conditions set forth therein.

               No recourse under or upon any obligation, covenant or agreement
contained in the Indenture, in any Security or coupon appertaining thereto, or
because of any indebtedness evidenced hereby or thereby (including, without
limitation, any obligation or indebtedness relating to the principal of, or
premium or Make-Whole Amount, if any, interest or any other amounts due, or
claimed to be due, on this Security), or for any claim based thereon or
otherwise in respect thereof, shall be had (i) against the General Partner or
any other partner, or any Person which owns an interest, directly or indirectly,
in any partner, in the Issuer, or (ii) against any promoter, as such, or against
any past, present or future shareholder, officer, trustee or partner, as such,
of the Issuer or the General Partner or of any successor, either directly or
through the Issuer or the General Partner or any successor, under any rule of
law, statute or constitutional provision or by the enforcement of any assessment
or by any legal or equitable proceeding or otherwise, all such liability being
expressly waived and released by the acceptance hereof and as part of the
consideration for the issue hereof.

               The Securities of this series are issuable only in registered
form without coupons in denominations of $1,000 and any integral multiple
thereof. As provided in the Indenture and subject to certain limitations therein
and herein set forth, this Note is exchangeable for a like aggregate principal
amount of Notes of different authorized denominations but otherwise having the
same terms and conditions, as requested by the Holder hereof surrendering the
same. No service charge shall be made for any such registration of transfer or
exchange, but the Issuer may require payment of a sum sufficient to cover any
tax or other governmental charge payable in connection therewith.

               Prior to due presentment of this Note for registration of
transfer, the Issuer, the Trustee and any agent of the Issuer or the Trustee may
deem and treat the Person in whose name this Security is registered as the
absolute owner of this Security (whether or not this Security shall be overdue
and notwithstanding any notation of ownership or other writing hereon), for the
purpose of receiving payment of, or on account of, the principal hereof and
Make-Whole Amount, if any, and subject to the provisions herein and on the face
hereof; interest hereon and for all other purposes, and neither the Issuer, the
Trustee nor any such agent shall be affected by notice to the contrary.

               THE INDENTURE AND THIS SECURITY SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.


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               Pursuant to a recommendation promulgated by the Committee on
Uniform Security Identification Procedures, the Issuer has caused CUSIP numbers
to be printed on the Notes as a convenience to the Holders of the Notes. No
representation is made as to the correctness or accuracy of such CUSIP numbers
as printed on the Notes, and reliance may be placed only on the other
identification numbers printed hereon.

               Capitalized terms used herein and not defined herein shall have
the respective meanings given to such terms in the Indenture.

               Unless the Certificate of Authentication hereon has been executed
by the Trustee by one of its authorized signatories, this Note shall not be
entitled to any benefit under the Indenture, or be valid or obligatory for any
purpose.




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        IN WITNESS WHEREOF, the Issuer has caused this instrument to be signed
        manually or by facsimile by its duly authorized officers.

Dated:  __________, 2000

                                        ARDEN REALTY LIMITED PARTNERSHIP



                                        By: Arden Realty, Inc., its sole general
                                            partner

                                        By:
                                           -------------------------------------
                                           Diana M. Laing
                                           Executive Vice President and
                                           Chief Financial Officer



Attest:

----------------------------------
David A. Swartz
General Counsel and Secretary


TRUSTEE'S CERTIFICATE OF AUTHENTICATION

This is one of the Notes of the series designated herein referred to in the
within-mentioned Indenture.



                                        THE BANK OF NEW YORK
                                                     as Trustee


                                        By:
                                           -------------------------------------
                                                  Authorized Signatory



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                   ASSIGNMENT FORM AND CERTIFICATE OF TRANSFER

To assign this Security fill in the form below:

(I) or (we) assign and transfer this Security to


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    (Insert assignee's social security or tax identification number, if any)

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--------------------------------------------------------------------------------

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              (Print or type assignee's name, address and zip code)

        Your signature:
                       ---------------------------------------------------------
                         (Sign exactly as your name appears on this Security)

        Date:
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        Signature Guarantee:*
                            ----------------

        In connection with any transfer of any of the Securities evidenced by
this certificate occurring prior to the date that is two years (or such shorter
period as may then be applicable under Rule 144(k) of the United States
Securities Act of 1933, as amended (the "Securities Act") (or any successor
provision)) after the later of the date of original issuance of such Securities
and the last date, if any, on which such Securities were owned by the Issuer or
any Affiliate of the Issuer, the undersigned confirms that such Securities are
being transferred:

        CHECK ONE BOX BELOW

        (1)    [ ]    to the Issuer or a Subsidiary thereof; or

        (2)    [ ]    pursuant to and in compliance with Rule 144A under the
                      Securities Act; or

        (3)    [ ]    pursuant to Rule 144 under the Securities Act; or

        (4)    [ ]    pursuant to an effective registration statement under the
                      Securities Act; or

        (5)    [ ]    pursuant to another available exemption from the
                      registration requirements of the Securities Act.

        Unless one of the boxes is checked, the Trustee will refuse to register
any of the Securities evidenced by this certificate in the name of any person
other than the registered holder thereof; provided, however, that if box (2),
(3), (4) or (5) is checked, the Trustee (as instructed by the Issuer) and the
Issuer may require, prior to registering any such transfer of the Securities,
such certifications, legal opinions or other information as the Issuer has
reasonably requested to confirm that such transfer is being made pursuant to an
exemption from, or in a transaction not subject to, the registration
requirements of the Securities Act.

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*       Signature must be guaranteed by a commercial bank, trust company or
        member firm or a major stock exchange