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                                                                    EXHIBIT 10.1

                PRENTISS PROPERTIES ACQUISITION PARTNERS, L.P.

          Eighth Amendment to the Second Amended and Restated Agreement of
Limited Partnership of Prentiss Properties Acquisition Partners, L.P.
Establishing the Series C Cumulative Redeemable Perpetual Preferred Units of
Partnership Interest and Fixing Distribution and Other Preferences and Rights of
Such Units.

                                 RECITALS

          A.  Pursuant to Section 4.02 and Article XI of the Second Amended and
Restated Agreement of Limited Partnership, as amended (as so amended, the

"Agreement"), of Prentiss Properties Acquisition Partners, L.P. (the
----------
"Partnership"), Prentiss Properties I, Inc. as the sole general partner of the
------------
Partnership (the "General Partner"), desires to amend the Agreement to establish
                  ---------------
a series of preferred units of partnership interest in the Partnership
designated as the Series C Cumulative Redeemable Perpetual Preferred Units (the
"Series C Preferred Units") with economic interests as set forth in this
 ------------------------
Amendment.

          NOW, THEREFORE, the General Partner hereby adopts the following
amendment to the Agreement.

          I.  Section 4.02 of the Agreement is amended by adding Section 4.02(f)
as follows, with appropriate conforming changes to the numbering and lettering
thereto:

          (f) Series C Cumulative Redeemable Perpetual Preferred Units of
Partnership Interest.

          Section 1.  Definitions.  Capitalized terms used herein and not
                      -----------
defined herein shall have the meaning given them in the Agreement.  For purposes
of the Series C Preferred Units, the following terms shall have the meanings
indicated:

          "Common Units" shall mean all the units of the Partnership that are
           ------------
not specifically designated as preferred units pursuant to Section 4.02.

          "Parity Preferred Units" shall be used to refer to any class or series
           ----------------------
of Partnership Interests of the Partnership now or hereafter authorized, issued
or outstanding expressly designated by the Partnership to rank on a parity with
Series C Preferred Units with respect to distributions and rights upon voluntary
or involuntary liquidation, winding-up or dissolution of the Partnership, and
includes the Series A Cumulative Convertible Redeemable Preferred Units of
Partnership Interest of the Partnership and the Series B Cumulative Redeemable
Perpetual Preferred Units of Partnership Interest of the Partnership.

          "PTP" shall mean a "publicly traded partnership" within the meaning of
           ---
Section 7704 of the Code.
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                                       2



          The definitions of "Profit" and "Loss" in the Agreement shall be
                              ------       ----
modified as follows:

               Solely for purposes of allocating Profit or Loss in any fiscal
     year of the Partnership to the holders of the Series C Preferred Units,
     items of Profit and Loss, as the case may be, shall not include
     depreciation with respect to properties that are "ceiling limited" in
     respect of the holders of the Series C Preferred Units.  For purposes of
     the preceding sentence, Partnership property shall be considered ceiling
     limited in respect of a holder of Series C Preferred Units if depreciation
     attributable to such Partnership property which would otherwise be
     allocable to such Partner, without regard to this paragraph, exceeded
     depreciation determined for federal income tax purposes attributable to
     such Partnership property which would otherwise be allocated to such
     Partner by more than 5%.

          Section 2.  Designation and Number.  A series of preferred units of
                      ----------------------
partnership interest in the Partnership designated as the "9.45% Series C
Cumulative Redeemable Perpetual Preferred Units" (the "Series C Preferred
                                                       ------------------
Units") is hereby established.  The number of Series C Preferred Units shall be
-----
2,000,000, which number may be decreased (but not below the aggregate number
thereof then outstanding and/or which have been reserved for issuance) from time
to time by the General Partner.

          Section 3.  Distributions.   (a)  Payment of Distributions.  Subject
                      -------------         ------------------------
to the rights of holders of Parity Preferred Units and holders of preferred
units ranking senior to the Series C Preferred Units issued after the date
hereof in accordance herewith as to payment of distributions and rights upon
voluntary or involuntary dissolution, liquidation or winding-up, holders of
Series C Preferred Units shall be entitled to receive, when, as and if declared
by the Partnership acting through the General Partner, out of funds legally
available for the payment of distributions, cumulative preferential cash
distributions at the rate per annum of 9.45% of the original Capital
Contribution per Series C Preferred Unit.  Such distributions shall be
cumulative and shall accrue from the first day of the applicable Distribution
Period (as defined herein), and will be payable (A) quarterly in arrears, not
later than the third calendar day after the end of the applicable Distribution
Period and (B) in the event of (i) an exchange of Series C Preferred Units into
Series C Preferred Shares, or (ii) a redemption of Series C Preferred Units, on
the exchange date or redemption date, as applicable (each a "Preferred Unit
                                                             --------------
Distribution Payment Date").  For purposes of this Amendment, the term
-------------------------
"Distribution Period" shall mean quarterly distribution periods commencing on
--------------------
January 1, April 1, July 1 and October 1 of each year and ending on and
including the day preceding the first day of the next succeeding Distribution
Period with respect to any Series C Preferred Units (other than the initial
Distribution Period, which shall commence on the original date of issuance for
such Series C Preferred Units and end on and include the last day of the
calendar quarter immediately following the original date of issuance, and other
than the Distribution Period during which any Series C Preferred Units shall be
redeemed or exchanged, which shall end on and include the date of such
redemption or exchange).  The amount of the distribution payable for any period
will be computed on the basis of a 360-day year of twelve 30-day
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                                       3

months and for any period shorter than a full quarterly period for which
distributions are computed, the amount of the distribution payable will be
computed on the basis of the ratio of the actual number of days elapsed in such
period to ninety (90) days. If any date on which distributions are to be made on
the Series C Preferred Units is not a Business Day (as defined herein), then
payment of the distribution to be made on such date will be made on the next
succeeding day that is a Business Day (and without any interest or other payment
in respect of any such delay) except that, if such Business Day is in the next
succeeding calendar year, such payment shall be made on the immediately
preceding Business Day, in each case with the same force and effect as if made
on such date. Distributions on the Series C Preferred Units will be made to the
holders of record of the Series C Preferred Units on October 1, 1999 and
thereafter on the relevant record dates to be fixed by the Partnership acting
through the General Partner, which record dates shall in no event exceed fifteen
(15) Business Days prior to the relevant Preferred Unit Distribution Payment
Date (the "Preferred Unit Partnership Record Date").
           --------------------------------------

          The term "Business Day" shall mean each day, other than a Saturday or
                    ------------
a Sunday, which is not a day on which banking institutions in New York, New York
are authorized or required by law, regulation or executive order to close.

          (b) Distributions Cumulative.  Distributions on the Series C Preferred
              ------------------------
Units will accrue and accumulate as of each Preferred Unit Distribution Payment
Date whether or not the terms and provisions of any agreement of the
Partnership, including any agreement relating to its indebtedness at any time
prohibit the current payment of distributions, whether or not the Partnership
has earnings, whether or not there are funds legally available for the payment
of such distributions and whether or not such distributions are authorized.
Distributions on account of arrears for any past Distribution Periods may be
declared and paid at any time, without reference to a regular Preferred Unit
Distribution Payment Date to holders of record of the Series C Preferred Units
on the record date fixed by the Partnership acting through the General Partner
which date shall not exceed fifteen (15) Business Days prior to the payment
date.  Accumulated and unpaid distributions will not bear interest.

          (c)  Priority as to Distributions.  (i)  So long as any Series C
               ----------------------------
Preferred Units are outstanding, no distribution of cash or other property shall
be authorized, declared, paid or set apart for payment on or with respect to any
class or series of Partnership Interest of the Partnership ranking junior to the
Series C Preferred Units as to the payment of distributions or rights upon
voluntary or involuntary liquidation, dissolution or winding-up (collectively,

"Junior Units"), nor shall any cash or other property be set aside for or
-------------
applied to the purchase, redemption or other acquisition for consideration of
any Series C Preferred Units, any Parity Preferred Units or any Junior Units,
unless, in each case, all distributions accumulated on all Series C Preferred
Units and all classes and series of outstanding Parity Preferred Units have been
paid in full.  The foregoing sentence will not prohibit (a) distributions
payable solely in classes or series of Partnership Interest ranking junior to
the Series C Preferred Units as to the payment of distributions and rights upon
voluntary or involuntary liquidation, dissolution or winding-up, (b) the
conversion of Junior Units or Parity Preferred Units into Partnership Interests
of the Partnership ranking junior to the Series C Preferred Units as to
distributions and rights upon
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                                       4

voluntary or involuntary liquidation, dissolution or winding-up, (c) the
redemption of Partnership Interests corresponding to any Series C Preferred
Shares, Parity Preferred Shares or Junior Shares to be purchased by Prentiss
Properties Trust (the "Trust") pursuant to Article VII of the Amended and
                       -----
Restated Declaration of Trust of the Trust (the "Declaration") to preserve
                                                 -----------
the Trust's status as a real estate investment trust, provided that such
redemption shall be upon the same terms as the corresponding purchase pursuant
to Article VII of the Declaration, or (d) the purchase, redemption or other
acquisition of Common Units made for the purpose of an employee incentive or
benefit plan of the Partnership or any subsidiary.

          (ii) So long as distributions have not been paid in full (or a sum
sufficient for such full payment is not irrevocably deposited in trust for
payment) upon the Series C Preferred Units, all distributions authorized and
declared on the Series C Preferred Units and all classes or series of
outstanding Parity Preferred Units shall be authorized and declared so that the
amount of distributions authorized and declared per Series C Preferred Unit and
such other classes or series of Parity Preferred Units shall in all cases bear
to each other the same ratio that accrued distributions per Series C Preferred
Unit and such other classes or series of Parity Preferred Units (which shall not
include any accumulation in respect of unpaid distributions for prior
distribution periods if such class or series of Parity Preferred Units do not
have cumulative distribution rights) bear to each other.

          (d)  No Further Rights.  Holders of Series C Preferred Units shall not
               -----------------
be entitled to any distributions, whether payable in cash, other property or
otherwise, in excess of the full cumulative distributions described herein.

          (e)  No distributions on Series C Preferred Units shall be declared by
the General Partner or paid or set apart for payment by the Partnership at such
time as the terms and provisions of any agreement of the Partnership, including
any agreement relating to its indebtedness, prohibits such declaration, payment
or provides that such declaration, payment or setting apart for payment would
constitute a breach thereof or a default thereunder, or if such declaration or
payment shall be restricted or prohibited by law. Nothing in this subsection (e)
shall be deemed to modify or affect in any manner the accrual provisions set
forth in Section 3(b) or the distribution priorities set forth in Section 3(c).

          (f) In the event of any conflict between the provisions of this
Section 3 and the provisions of Section 5.02(a) of the Agreement, the provisions
of this Section 3 shall control.

          Section 4.  Liquidation Proceeds.  (a) Subject to the rights of
                      --------------------
holders of Parity Preferred Units and subject to preferred units ranking senior
to the Series C Preferred Units with respect to rights upon any voluntary or
involuntary liquidation, dissolution or winding-up of the
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                                       5

Partnership, the holders of Series C Preferred Units shall be entitled to
receive out of the assets of the Partnership legally available for distribution
or the proceeds thereof, after payment or provision for debts and other
liabilities of the Partnership, but before any payment or distributions of the
assets shall be made to holders of Common Units or any other class or series of
Partnership Interests of the Partnership that ranks junior to the Series C
Preferred Units as to rights upon liquidation, dissolution or winding-up of the
Partnership, an amount equal to the sum of (i) a liquidation preference in an
amount equal to the positive Capital Account balance of the holder of the Series
C Preferred Units, determined after taking into account all Capital Account
adjustments for the Partnership taxable year during which the liquidation occurs
(other than those made as a result of the liquidating distribution set forth in
this Section 4) and (ii) an amount equal to any accumulated and unpaid
distributions thereon, whether or not declared, to the date of payment to the
extent such distributions are not reflected in the Capital Account balance as of
the date of payment. In the event that, upon such voluntary or involuntary
liquidation, dissolution or winding-up, there are insufficient assets to permit
full payment of liquidating distributions to the holders of Series C Preferred
Units and any Parity Preferred Units as to rights upon liquidation, dissolution
or winding-up of the Partnership, all payments of liquidating distributions on
the Series C Preferred Units and such Parity Preferred Units shall be made so
that the payments on the Series C Preferred Units and such Parity Preferred
Units shall in all cases bear to each other the same ratio that the respective
rights of the Series C Preferred Units and such other Parity Preferred Units
(which shall not include any accumulation in respect of unpaid distributions for
prior distribution periods if such Parity Preferred Units do not have cumulative
distribution rights) upon liquidation, dissolution or winding-up of the
Partnership bear to each other. In the event of any conflict between the
provisions of this Section 4 and the provisions of Section 5.06 of the
Agreement, the provisions of this Section 4 shall control.

          (b) Notice.  Written notice of any such voluntary or involuntary
              ------
liquidation, dissolution or winding-up of the Partnership, stating the payment
date or dates when, and the place or places where, the amounts distributable in
such circumstances shall be payable, shall be given by (i) fax (if the holder of
the Series C Preferred Units shall have provided the Partnership with such
holder's fax number) and (ii) first class mail, postage pre-paid, not less than
30 and not more that 60 days prior to the payment date stated therein, to each
record holder of the Series C Preferred Units at the respective addresses of
such holders as the same shall appear on the transfer records of the
Partnership.

          (c) No Further Rights.  After payment of the full amount of the
              -----------------
liquidating distributions to which they are entitled, the holders of Series C
Preferred Units will have no right or claim to any of the remaining assets of
the Partnership.

          (d) Consolidation, Merger or Certain Other Transactions.  The
              ---------------------------------------------------
voluntary sale, conveyance, lease, exchange or transfer (for cash, shares of
stock, securities or other consideration) of all or substantially all of the
property or assets of the Partnership to, or the  consolidation or merger or
other business combination of the Partnership with or into, any corporation,
trust or other
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                                       6

entity (or of any corporation, trust or other entity with or into
the Partnership) shall not be deemed to constitute a liquidation, dissolution or
winding-up of the Partnership.

          Section 5.  Optional Redemption.  (a)  Right of Optional Redemption.
                      --------------------       ----------------------------
The Series C Preferred Units may not be redeemed prior to the fifth anniversary
of the issuance date.  On or after such date, the Partnership shall have the
right to redeem the Series C Preferred Units, in whole or in part, at any time
or from time to time out of funds legally available therefor, upon not less than
30 nor more than 60 days' written notice, at a redemption price, payable in
cash, equal to the Capital Account balance (or, if not redeemed in full, the
applicable portion thereof) of the holder of the Series C Preferred Units (the

"Redemption Price"); provided, however, that no redemption pursuant to this
-----------------
Section 5 will be permitted if the Redemption Price does not equal or exceed the
original Capital Contribution (or, if not redeemed in full, the applicable
portion thereof) per unit of Series C Preferred Units, plus accumulated and
unpaid distributions, whether or not declared, to the date of redemption to the
extent such distributions are not reflected in the Capital Account balance as of
the date of redemption.  If fewer than all of the outstanding Series C Preferred
Units are to be redeemed, the Series C Preferred Units to be redeemed shall be
selected pro rata (as nearly as practicable without creating fractional units).

          (b) Limitation on Redemption. (i) The Redemption Price of the Series C
              ------------------------
Preferred Units (other than the portion thereof consisting of accumulated but
unpaid distributions) will be payable solely out of the sale proceeds of capital
stock of the Trust, which will be contributed by the Trust to the Partnership as
additional capital contribution, or out of the sale of limited partner interests
in the Partnership and from no other source. For purposes of the preceding
sentence, "capital stock" means any equity securities (including Common Shares
and Preferred Shares (as such terms are defined in the Declaration)), shares,
participation or other ownership interests (however designated) and any rights
(other than debt securities convertible into or exchangeable for equity
securities) or options to purchase any of the foregoing.

          (ii) The Partnership may not redeem fewer than all of the outstanding
Series C Preferred Units unless all accumulated and unpaid distributions have
been paid on all Series C Preferred Units for all quarterly Distribution Periods
terminating on or prior to the date of redemption.

          (c)  Procedures for Redemption.  (i) Notice of redemption will be (i)
               -------------------------
faxed (if the holder of the Series C Preferred Units shall have provided the
Partnership with such holder's fax number) and (ii) mailed by the Partnership,
by certified mail, postage prepaid, not less than 30 nor more than 60 days prior
to the redemption date, addressed to the respective holders of record of the
Series C Preferred Units at their respective addresses as they appear on the
records of the Partnership.  No failure to give or defect in such notice shall
affect the validity of the proceedings for the redemption of any Series C
Preferred Units except as to the holder to whom such notice was defective or not
given.  In addition to any information required by law, each such notice shall
state:
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                                       7

(i) the redemption date, (ii) the Redemption Price, (iii) the aggregate
number of Series C Preferred Units to be redeemed and if fewer than all of the
outstanding Series C Preferred Units are to be redeemed, the number of Series C
Preferred Units to be redeemed held by such holder, (iv) the place or places
where such Series C Preferred Units are to be surrendered for payment of the
Redemption Price, (v) that distributions on the Series C Preferred Units to be
redeemed will cease to accumulate on such redemption date and (vi) that payment
of the Redemption Price will be made upon presentation and surrender of such
Series C Preferred Units.

          (ii) If the Partnership gives a notice of redemption in respect of
Series C Preferred Units (which notice will be irrevocable) then, by 12:00 noon,
New York City time, on the redemption date, the Partnership will deposit
irrevocably in trust for the benefit of the Series C Preferred Units being
redeemed funds sufficient to pay the applicable Redemption Price, plus any
accumulated and unpaid distributions, whether or not declared, if any, on such
units to the date fixed for redemption, without interest, and will give
irrevocable instructions and authority to pay such Redemption Price to the
holders of the Series C Preferred Units upon surrender of the Series C Preferred
Units by such holders at the place designated in the notice of redemption.  If
the Series C Preferred Units are evidenced by a certificate and if fewer than
all Series C Preferred Units evidenced by any certificate are being redeemed, a
new certificate shall be issued upon surrender of the certificate evidencing all
Series C Preferred Units, evidencing the unredeemed Series C Preferred Units
without cost to the holder thereof.  On and after the date of redemption,
distributions will cease to accumulate on the Series C Preferred Units or
portions thereof called for redemption, unless the Partnership defaults in the
payment thereof, such units will no longer be deemed outstanding, and all rights
of the holders thereof as holders of Series C Preferred Units will cease (except
the right to receive the Redemption Price and any accrued and unpaid
distributions upon surrender and endorsement of the certificates evidencing the
Series C Preferred Units, if any).  If any date fixed for redemption of Series C
Preferred Units is not a Business Day, then payment of the Redemption Price
payable on such date will be made on the next succeeding day that is a Business
Bay (and without any interest or other payment in respect of any such delay)
except that, if such Business Day falls in the next calendar year, such payment
will be made on the immediately preceding Business Day, in each case with the
same force and effect as if made on such date fixed for redemption.  If payment
of the Redemption Price is improperly withheld or refused and not paid by the
Partnership, distributions on such Series C Preferred Units will continue to
accumulate from the original redemption date to the date of payment, in which
case the actual payment date will be considered the date fixed for redemption
for purposes of calculating the applicable Redemption Price.

          Section 6.  Voting Rights.  (a)  General.  Holders of  the Series C
                      -------------        -------
Preferred Units will not have any voting rights or right to consent to any
matter requiring the consent or approval of the Limited Partners, except as set
forth below.

          (b)  Certain Voting Rights.  So long as any Series C Preferred Units
               ---------------------
remains outstanding, the Partnership shall not, without the affirmative vote of
the holders of at least two-
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                                       8

thirds of the Series C Preferred Units outstanding at the time, (i) authorize or
create, or increase the authorized or issued amount of, any class or series of
Partnership Interests ranking prior to the Series C Preferred Units with respect
to payment of distributions or rights upon liquidation, dissolution or winding-
up or reclassify any Partnership Interests of the Partnership into any such
Partnership Interest, or create, authorize or issue any obligations or security
convertible into or evidencing the right to purchase any such Partnership
Interests, (ii) create in favor of or issue to an affiliate of the Partnership
any Parity Preferred Units or reclassify any Partnership Interest of the
Partnership held by an affiliate of the Partnership into any such Partnership
Interest or create, authorize or issue in favor of or to any affiliate of the
Partnership any obligations or security convertible into or evidencing the right
to purchase any Parity Preferred Units, other than to the Trust to the extent
the issuance of such interests was to allow the Trust to issue corresponding
preferred shares to persons who are not affiliates of the Partnership or (iii)
either (A) consolidate, merge into or with, or convey, transfer or lease its
assets substantially as an entirety to, any corporation or other entity or (B)
amend, alter or repeal the provisions of the Agreement or this Amendment,
whether by merger, consolidation or otherwise, that would materially and
adversely affect the powers, special rights, preferences, privileges or voting
power of the Series C Preferred Units or the holders thereof; provided, however,
that with respect to the occurrence of a merger, consolidation or a sale or
lease of all of the Partnership's assets as an entirety, so long as (a) the
Partnership is the surviving entity and the Series C Preferred Units remain
outstanding without a change to the terms thereof, or (b) the resulting,
surviving or transferee entity is a partnership, limited liability company or
other pass-through entity organized under the laws of any state and substitutes
the Series C Preferred Units for other interests in such entity having
substantially the same terms and rights as the Series C Preferred Units,
including with respect to distributions, voting rights and rights upon
liquidation, dissolution or winding-up, then the occurrence of any such event
shall not be deemed to materially and adversely affect such rights, preferences,
privileges or voting powers of the Series C Preferred Units and the holders
thereof, and provided further that any increase in the amount of Partnership
Interests or the creation or issuance of any other class or series of
Partnership Interests, in each case ranking (a) junior to the Series C Preferred
Units with respect to payment of distributions and the distribution of assets
upon liquidation, dissolution or winding-up, or (b) on a parity to the Series C
Preferred Units with respect to payment of distributions and the distribution of
assets upon liquidation, dissolution or winding-up, to the extent such
Partnership Interests are not issued to an affiliate of the Partnership, other
than the Trust to the extent the issuance of such interests was to allow the
Trust to issue corresponding preferred shares to persons who are not affiliates
of the Partnership, shall not be deemed to materially and adversely affect such
rights, preferences, privileges or voting powers.

          Section 7.  Transfer Restrictions.  The Series C Preferred Units shall
                      ---------------------
be subject to the provisions of Article IX of the Partnership Agreement.

          Section 8.  Exchange Rights.  (a)  Right to Exchange.  (i)  Series C
                      ---------------        -----------------
Preferred Units will be exchangeable in whole or in part at anytime on or after
the tenth anniversary of the date of issuance, at the option of the holders
thereof, for authorized but previously unissued shares of
<PAGE>

                                       9

9.45% Series C Cumulative Redeemable Preferred Shares of the Trust (the "Series
                                                                         ------
C Preferred Shares") at an exchange rate of one share of Series C Preferred
------------------
Shares for one Series C Preferred Unit, subject to adjustment as described below
(the "Exchange Price"), provided that the Series C Preferred Units will become
      --------------
exchangeable at any time, in whole or in part, at the option of the holders of
Series C Preferred Units for Series C Preferred Shares if (y) at any time full
distributions shall not have been timely made on any Series C Preferred Unit
with respect to six (6) prior quarterly distribution periods, whether or not
consecutive, provided, however, that a distribution in respect of Series C
Preferred Units shall be considered timely made if made within two (2) Business
Days after the applicable Preferred Unit Distribution Payment Date if at the
time of such late payment there shall not be any prior quarterly distribution
periods in respect of which full distributions were not timely made or (z) upon
receipt by a holder or holders of Series C Preferred Units of (A) notice from
the General Partner that the General Partner or a Subsidiary of the General
Partner has taken the position that the Partnership is, or upon the occurrence
of a defined event in the immediate future will be, a PTP and (B) an opinion
rendered by an outside nationally recognized independent counsel familiar with
such matters addressed to a holder or holders of Series C Preferred Units, that
the Partnership is or likely is, or upon the occurrence of a defined event in
the immediate future will be or likely will be, a PTP. In addition, the Series C
Preferred Units may be exchanged for Series C Preferred Shares, in whole or in
part, at the option of any holder prior to the tenth anniversary of the issuance
date and after the third anniversary thereof if such holder of a Series C
Preferred Units shall deliver to the General Partner either (i) a private ruling
letter addressed to such holder of Series C Preferred Units or (ii) an opinion
of independent counsel reasonably acceptable to the General Partner based on the
enactment of temporary or final Treasury Regulations or the publication of a
Revenue Ruling, in either case to the effect that an exchange of the Series C
Preferred Units at such earlier time would not cause the Series C Preferred
Units to be considered "stock and securities" within the meaning of section
351(e) of the Code for purposes of determining whether the holder of such Series
C Preferred Units is an "investment company" under section 721(b) of the Code if
an exchange is permitted at such earlier date. Furthermore, the Series C
Preferred Units may be exchanged in whole but not in part by any holder thereof
which is a real estate investment trust within the meaning of Sections 856
through 859 of the Code for Series C Preferred Shares (but only if the exchange
in whole may be accomplished consistently with the ownership limitations set
forth under Article VII of the Declaration (taking into account exceptions
thereto)) if at any time, (i) the Partnership reasonably determines that the
assets and income of the Partnership for a taxable year after 1999 would not
satisfy the income and assets tests of Section 856 of the Code for such taxable
year if the Partnership were a real estate investment trust within the meaning
of the Code or (ii) any such holder of Series C Preferred Units shall deliver to
the Partnership and the General Partner an opinion of independent counsel
reasonably acceptable to the Trust to the effect that, based on the assets and
income of the Partnership for a taxable year after 1999, the Partnership would
not satisfy the income and assets tests of Section 856 of the Code for such
taxable year if the Partnership were a real estate investment trust within the
meaning of the Code and that such failure would create a meaningful risk that a
holder of the Series C Preferred Units would fail to maintain qualification as a
real estate investment trust.
<PAGE>

                                       10

          (ii) Notwithstanding anything to the contrary set forth in Section
8(a)(i), if an Exchange Notice (as defined herein) has been delivered to the
General Partner, then the General Partner may, at its option, elect to redeem or
cause the Partnership to redeem all or a portion of the outstanding Series C
Preferred Units for cash in an amount equal to the original Capital Contribution
per Series C Preferred Unit and all accrued and unpaid distributions thereon to
the date of redemption. The General Partner may exercise its option to redeem
the Series C Preferred Units for cash pursuant to this Section 8(a)(ii) by
giving each holder of record of Series C Preferred Units notice of its election
to redeem for cash, within five (5) Business Days after receipt of the Exchange
Notice, by (i) fax (if the holder of the Series C Preferred Units shall have
provided the Partnership with such holder's fax number) and (ii) registered
mail, postage paid, at the address of each holder as it may appear on the
records of the Partnership stating (i) the redemption date, which shall be no
later than sixty (60) days following the receipt of the Exchange Notice, (ii)
the redemption price, (iii) the place or places where the Series C Preferred
Units are to be surrendered for payment of the redemption price, (iv) that
distributions on the Series C Preferred Units will cease to accrue on such
redemption date; (v) that payment of the redemption price will be made upon
presentation and surrender of the Series C Preferred Units and (vi) the
aggregate number of Series C Preferred Units to be redeemed, and if fewer than
all of the outstanding Series C Preferred Units are to be redeemed, the number
of Series C Preferred Units to be redeemed held by such holder, which number
shall equal such holder's pro-rata share (based on the percentage of the
aggregate number of outstanding Series C Preferred Units the total number of
Series C Preferred Units held by such holder represents) of the aggregate number
of Series C Preferred Units being redeemed.

          (iii)  In the event an exchange of all or a portion of Series C
Preferred Units pursuant to Section 8(a)(i) would violate the provisions on
ownership limitation of the Trust set forth in Article VII of the Declaration,
the General Partner shall give written notice thereof to each holder of record
of Series C Preferred Units, within five (5) Business Days following receipt of
the Exchange Notice, by fax (if the holder of the Series C Preferred Units shall
have provided the Partnership with such holder's fax number) and (ii) registered
mail, postage prepaid, at the address of each such holder set forth in the
records of the Partnership.  In such event, each holder of Series C Preferred
Units shall be entitled to exchange, pursuant to the provision of Section 8(b) a
number of Series C Preferred Units which would comply with the provisions on the
ownership limitation of the Trust set forth in such Article VII of the
Declaration and any Series C Preferred Units not so exchanged (the "Excess
                                                                    ------
Units") shall be redeemed by the Partnership for cash in an amount equal to the
-----
original Capital Contribution per Excess Unit, plus any accrued and unpaid
distributions thereon, whether or not declared, to the date of redemption. The
written notice of the General Partner shall state (i) the number of Excess Units
held by such holder, (ii) the redemption price of the Excess Units, (iii) the
date on which such Excess Units shall be redeemed, which date shall be no later
than sixty (60) days following the receipt of the Exchange Notice, (iv) the
place or places where such Excess Units are to be surrendered for payment of the
redemption price, (v) that distributions on the Excess Units will cease to
accrue on such redemption date, and (vi) that payment of the redemption price
will be made upon presentation and surrender of such Excess Units. In the
<PAGE>

                                       11

event an exchange would result in Excess Units, as a condition to such exchange,
each holder of such units agrees to provide representations and covenants
reasonably requested by the General Partner relating to (i) the widely held
nature of the interests in such holder, sufficient to assure the General Partner
that the holder's ownership of stock of the Trust (without regard to the limits
described above) will not cause any individual to own in excess of 9.8% of the
stock of the Trust; and (ii) to the extent such holder can so represent and
covenant without obtaining information from its owners, the holder's ownership
of tenants of the Partnership and its affiliates.

          (iv) The redemption of Series C Preferred Units described in Section
8(a)(ii) and (iii) shall be subject to the provisions of Section 5(c)(ii);
provided, however, that for the purposes hereof the term "Redemption Price" in
Section 5(c)(ii) shall be read to mean the original Capital Contribution per
Series C Preferred Unit being redeemed, plus any accumulated and unpaid
distributions, whether or not declared, to the date of redemption to the extent
not otherwise accounted for therein.

          (b) Procedure for Exchange.  (i) Any exchange shall be exercised
              ----------------------
pursuant to a notice of exchange (the "Exchange Notice") delivered to the
                                       ---------------
General Partner by the holder who is exercising such exchange right, by fax (if
the holder of the Series C Preferred Units shall have provided the Partnership
with such holder's fax number) and certified mail postage prepaid.  The exchange
of Series C Preferred Units, or a specified portion thereof, may be effected
after the fifth (5th) Business Days following receipt by the General Partner of
the Exchange Notice by delivering certificates, if any, representing such Series
C Preferred Units to be exchanged together with, if applicable, written notice
of exchange and a proper assignment of such Series C Preferred Units to the
office of the General Partner maintained for such purpose.  Currently, such
office is located at 3890 W. Northwest Highway, Suite 400, Dallas, Texas 75220.
Each exchange will be deemed to have been effected immediately prior to the
close of business on the date on which such Series C Preferred Units to be
exchanged (together with all required documentation) shall have been surrendered
and notice shall have been received by the General Partner as aforesaid and the
Exchange Price shall have been paid. Any Series C Preferred Shares issued
pursuant to this Section 8 shall be delivered as shares which are duly
authorized, validly issued, fully paid and nonassessable, free of pledge, lien,
encumbrance or restriction other than those provided in the Declaration, the
Bylaws of the Trust, the Securities Act and relevant state securities or blue
sky laws.

          (ii) In the event of an exchange of Series C Preferred Units for
shares of Series C Preferred Shares, an amount equal to the accrued and unpaid
distributions, whether or not declared, to the date of exchange on any Series C
Preferred Units tendered for exchange shall (a) accrue on the shares of the
Series C Preferred Shares into which such Series C Preferred Units are
exchanged, and (b) continue to accrue on such Series C Preferred Units, which
shall remain outstanding following such exchange, with the Trust as the holder
of such Series C Preferred Units. Notwithstanding anything to the contrary set
forth herein, in no event shall a holder of a Series C Preferred Unit that was
validly exchanged into Series C Preferred Shares pursuant to this section
<PAGE>

                                       12

(other than the Trust now holding such Series C Preferred Unit), receive a
distribution out of funds legally available for the payment of distributions, if
such holder, after exchange, is entitled to receive a distribution out of funds
legally available for the payment of distributions with respect to the share of
Series C Preferred Shares for which such Series C Preferred Unit was exchanged
or redeemed.

          (iii)  Fractional shares of Series C Preferred Shares are not to be
issued upon exchange but, in lieu thereof, the General Partner will pay a cash
adjustment based upon the fair market value of the Series C Preferred Shares on
the day prior to the exchange date as determined in good faith by the Board of
Trustees of the Trust.

          (c)  Adjustment of Exchange Price.   (i)  The Exchange Price is
               ----------------------------
subject to adjustment upon certain events, including, (a) subdivisions,
combinations and reclassification of the Series C Preferred Shares, and (b)
distributions to all holders of Series C Preferred Shares of evidences of
indebtedness of the Trust or assets (including securities, but excluding
dividends and distributions paid in cash out of equity applicable to Series C
Preferred Shares).

          (ii) In case the Trust shall be a party to any transaction (including,
without limitation, a merger, consolidation, statutory share exchange, tender
offer for all or substantially all of the Trust's capital shares or sale of all
or substantially all of the Trust's assets), in each case as a result of which
the Series C Preferred Shares will be converted into the right to receive shares
of capital stock, other securities or other property (including cash or any
combination thereof), each Series C Preferred Unit will thereafter be
exchangeable into the kind and amount of shares of capital stock and other
securities and property receivable (including cash or any combination thereof)
upon the consummation of such transaction by a holder of that number of shares
of Series C Preferred Shares or fraction thereof into which one Series C
Preferred Unit was exchangeable immediately prior to such transaction.  The
Trust may not become a party to any such transaction unless the terms thereof
are consistent with the foregoing.  In addition, the Trust shall not issue any
Additional Securities without the consent of the holders of the Series C
Preferred Units if such consent would be required to be obtained from holders of
Series C Preferred Shares and such Series C Preferred Shares were outstanding.

          Section 9.  No Conversion Rights.  The holders of the Series C
                      --------------------
Preferred Units shall not have any rights to convert such shares into shares of
any other class or series of stock or into any other securities of, or interest
in, the Partnership.

          Section 10.  No Sinking Fund.  No sinking fund shall be established
                       ---------------
for the retirement or redemption of Series C Preferred Units.

          Section 11.  Record Holders.  The General Partner may deem and treat
                       --------------
the record holder of any Series C Preferred Unit as the true and lawful owner
thereof for all purposes, and the General Partner shall not be affected by any
notice to the contrary.
<PAGE>

                                       13

          II.  Amendment to Section 5.01.  Section 5.01 is amended by amending
               -------------------------
and restating in its entirety Section 5.01(a), as follows:

          (a)  General.
               -------

          (1)  Profit.
               ------

          (A) First, 100% to the General Partner and Common Unitholders until
     the aggregate amount of Profit allocated under this Section 5.01(a)(1)(A),
                                                         ---------------------
     shall equal the aggregate amount of Loss allocated to the Partners under

     Section 5.01(a)(2)(E);
     ---------------------

          (B) Second, 100% to each Series A Preferred Unitholder, Series B
     Preferred Unitholder and Series C Preferred Unitholder in proportion to and
     to the extent of their respective excesses of (i) the aggregate amount of
     Loss allocated to each under Section 5.01(a)(2)(D) over (ii) the aggregate
                                  ---------------------
     amount of Profit allocated to each under this Section 5.01(a)(1)(B);
                                                   ---------------------

          (C) Third, 100% to the General Partner and the Common Unitholders in
     proportion to and to the extent of their respective excesses of (i) the
     aggregate amount of Loss allocated to each under Section 5.01(a)(2)(C) over
                                                      ---------------------
     (ii) the aggregate amount of Profit allocated to each under this Section
                                                                      -------
     5.01(a)(1)(C);
     -------------

          (D) Fourth, 100% proportionately to (i) each Series A Preferred
     Unitholder until the aggregate amount of Profit allocated to each Series A
     Preferred Unitholder under this Section 5.01(a)(1)(D)(i) shall equal the
                                     ------------------------
     Series A Preferred Distribution Amount, (ii) each Series B Preferred
     Unitholder until the aggregate amount of Profit allocated to each Series B
     Preferred Unitholder under this Section 5.01(a)(1)(D)(ii) shall equal the
                                     -------------------------
     Series B Preferred Distribution Amount and (iii) each Series C Preferred
     Unitholder until the aggregate amount of Profit allocated to each Series C
     Unitholder under this Section 5.01(a)(1)(D)(iii) shall equal the Series C
                           --------------------------
     Preferred Distribution Amount;  and

          (E) Fifth, 100% to the General Partner and the Common Unitholders in
     accordance with the Percentage Interest of each.

          (2)  Loss.
               ----

          (A) First, 100% to the General Partner and the Common Unitholders to
     the extent of and in proportion to (i) the aggregate amount of Profit
     allocated to each under Section 5.01(a)(1)(E) over (ii) the aggregate
                             ---------------------
     amount of Loss allocated to each under this Section 5.01(a)(2)(A);
                                                 ---------------------
<PAGE>

                                       14

          (B) Second 100% proportionately to (i) each Series A Preferred
     Unitholder to the extent of the Undistributed Series A Preferred Unit
     Distribution Amount, (ii) each Series B Preferred Unitholder to the extent
     of the Undistributed Series B Preferred Unit Distribution Amount and (iii)
     each Series C Preferred Unitholder to the extent of the Undistributed
     Series C Preferred Unit Distribution Amount;

          (C) Third, 100% to the General Partner and the Common Unitholders in
     proportion to the Percentage Interest of each until the Capital Account
     balances of both the General Partner and each Common Unitholder shall equal
     zero;

          (D) Fourth, 100% to each Series A Preferred Unitholder, Series B
     Preferred Unitholder and Series C Preferred Unitholder in proportion to the
     Capital Account balances of each until the Capital Account balances of each
     Series A Preferred Unitholder, Series B Preferred Unitholder and Series C
     Preferred Unitholder shall equal zero; and

          (E) Fifth, 100% to the General Partner and Common Unitholders in
     accordance with their Percentage Interests.

          (3) Definitions.  For purposes of this Section 5.01(a), the following
              -----------
terms shall have the meanings indicated:

          "Common Unitholder(s)" means all Persons holding a Limited Partnership
           --------------------
     Interest in the Partnership other than the Series A Preferred Unitholder
     and the Series B Preferred Unitholder.

          "Series A Preferred Unit Distribution Amount" means the amount
           -------------------------------------------
     distributable to the Series A Preferred Unitholders as provided in Section
     4.02(d) of the First Amendment to the Second Amended and Restated Agreement
     of Limited Partnership of the Partnership dated December 29, 1997.

          "Series A Preferred Unitholder" means any Person holding Series A
           -----------------------------
     Preferred Units.

          "Series A Preferred Units" means the Series A Cumulative Convertible
           ------------------------
     Redeemable Preferred Units of Partnership Interest issued pursuant to the
     First Amendment to the Second Amended and Restated Agreement of Limited
     Partnership of the Partnership dated December 29, 1997.

          "Series B Preferred Unit Distribution Amount" means the amount
           -------------------------------------------
     distributable to the Series B Unitholders as provided in Section 3 of
     Section 4.02(e) of the Agreement, which has been added to the Agreement by
     the Second Amendment to the Second Amended and
<PAGE>

                                       15

Restated Agreement of Limited Partnership of the Partnership dated June 25,
1998 (the "Second Amendment").

          "Series B Preferred Unitholder" means any Person holding Series B
           -----------------------------
     Preferred Units.

          "Series B Preferred Units" means the Series B Cumulative Redeemable
           ------------------------
     Perpetual Preferred Units of Partnership Interest issued pursuant to the
     Second Amendment to the Second Amended and Restated Agreement of Limited
     Partnership of the Partnership dated June 25, 1998.

          "Series C Preferred Unit Distribution Amount" means the amount
           -------------------------------------------
     distributable to the Series C Unitholders as provided in Section 3 of
     Section 4.02(f) of the Agreement, which has been added to the Agreement by
     the Eighth Amendment to the Second Amended and Restated Agreement of
     Limited Partnership of the Partnership dated September 17, 1999.

          "Series C Preferred Unitholder" means any Person holding Series C
           -----------------------------
     Preferred Units.

          "Series C Preferred Units" means the Series C Cumulative Redeemable
           ------------------------
     Perpetual Preferred Units of Partnership Interest issued pursuant to the
     Eighth Amendment to the Second Amended and Restated Agreement of Limited
     Partnership of the Partnership dated September 17, 1999.

          "Undistributed Series A Preferred Unit Distribution Amount" means the
           ---------------------------------------------------------
     excess of (i) the aggregate amount of Profit allocated to the Series A
     Unitholders under Section 5.01(a)(1)(D) and (ii) the aggregated amount of
                       ---------------------
     distributions made to the Series A Unitholder under Section 3 of Section
     4.02(d) of the First Amendment to the Second Amended and Restated Agreement
     of Limited Partnership of the Partnership dated December 29, 1997.

          "Undistributed Series B Preferred Unit Distribution Amount" means the
           ---------------------------------------------------------
     excess of (i) the aggregate amount of Profit allocated to the Series B
     Unitholders under Section 5.01(a)(1)(D) and (ii) the aggregated amount of
                       ---------------------
     distributions made to the Series B Unitholder under Section 3 of Section
     4.02(e) of the Second Amendment to the Second Amended and Restated
     Agreement of Limited Partnership of the Partnership dated June 25, 1998.

          "Undistributed Series C Preferred Unit Distribution Amount" means the
           ---------------------------------------------------------
     excess of (i) the aggregate amount of Profit allocated to the Series C
     Unitholders under Section 5.01(a)(1)(D) and (ii) the aggregated amount of
                       ---------------------
     distributions made to the Series C Unitholder under Section 3 of Section
     4.02(f) which has been added to the Agreement by the Eighth
<PAGE>

                                       16

     Amendment to the Second Amended and Restated Agreement of Limited
     Partnership of the Partnership dated September 17, 1999.

          III.  Amendments to Second Amendment.  The Second Amendment is hereby
                ------------------------------
amended as follows:

          (1)   The last sentence of Section 8(a)(i) of 4.02(e) which was added
     to the Agreement by the Second Amendment shall be deleted and the following
     shall be inserted in lieu thereof:

          Furthermore, the Series B Preferred Units may be exchanged in whole
          but not in part by any holder thereof which is a real estate
          investment trust within the meaning of Sections 856 through 859 of the
          Code for Series B Preferred Shares (but only if the exchange in whole
          may be accomplished consistently with the ownership limitations set
          forth under Article VII of the Declaration (taking into account
          exceptions thereto)) if at any time, (i) the Partnership reasonably
          determines that the assets and income of the Partnership for a taxable
          year after 1999 would not satisfy the income and assets tests of
          Section 856 of the Code for such taxable year if the Partnership were
          a real estate investment trust within the meaning of the Code or (ii)
          any such holder of Series B Preferred Units shall deliver to the
          Partnership and the General Partner an opinion of independent counsel
          reasonably acceptable to the Trust to the effect that, based on the
          assets and income of the Partnership for a taxable year after 1999,
          the Partnership would not satisfy the income and assets tests of
          Section 856 of the Code for such taxable year if the Partnership were
          a real estate investment trust within the meaning of the Code and that
          such failure would create a meaningful risk that a holder of the
          Series B Preferred Units would fail to maintain qualification as a
          real estate investment trust.

          (2) The following shall be inserted at the end of Section 8(c)(ii) of
Section 4.02(e) of the Agreement added to the Agreements by the Second
Amendment:

               In addition, the Trust shall not issue any Additional Securities
          without the consent of the holders of the Series B Preferred Units if
          such consent would be required to be obtained from holders of Series B
          Preferred Shares and such Series B Preferred Shares were outstanding.
<PAGE>

                                       17

          (d)  Exhibit A.
               ---------

          Exhibit A to the Agreement is hereby amended and restated in its
entirety as set forth on Exhibit A attached hereto.
                         ---------


                                 [signature page follows]
<PAGE>



          IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of September 17, 1999.


                              GENERAL PARTNER:

                              PRENTISS PROPERTIES I, INC.



                              By:  /S/ MICHAEL A. ERNST
                                   ___________________________
                                   Name:  MICHAEL A. ERNST
                                   Title:  SENIOR VICE PRESIDENT
                                           CHIEF FINANCIAL OFFICER



                              LIMITED PARTNERS:

                              BELAIR REAL ESTATE CORPORATION


                                  By: /S/ WILLIAM CROSS
                                      ________________________
                                      Name:  WILLIAM R. CROSS
                                      Title:  VICE PRESIDENT



                              BELCREST REALTY CORPORATION


                                  By: /S/ WILLIAM CROSS
                                      ________________________
                                      Name:  WILLIAM R. CROSS
                                      Title:  VICE PRESIDENT
<PAGE>



                                 ACKNOWLEDGMENT

          The Trust referred to in the foregoing Eighth Amendment to the Second
Amended and Restated Agreement of Limited Partnership of Prentiss Properties
Acquisition Partners, L.P. hereby acknowledges receipt of a copy thereof and
agrees to be bound thereby and to comply with the terms thereof insofar as such
terms are applicable to the Trust.


                                  PRENTISS PROPERTIES TRUST



                                  By:  /S/ MICHAEL A. ERNST
                                       _______________________
                                       Name:  MICHAEL A. ERNST
                                       Title:  SENIOR VICE PRESIDENT
                                               Chief Financial Officer
<PAGE>
                                  EXHIBIT A
                                  ---------
<TABLE>
        Partner                              Partnership      Percentage
                                               Units           Interest
<S>                                          <C>              <C>
Operating Partnership Units (Common)
------------------------------------

General Partner:

PRENTISS PROPERTIES I, INC.                      47,152          0.1130%
3890 W. Northwest Hwy. Ste. 400
Dallas, TX 75220

Limited Partners:

PRENTISS PROPERTIES TRUST                    39,981,497         95.8397%
3890 W. Northwest Hwy. Ste. 400
Dallas, TX 75220

MICHAEL V. PRENTISS                             262,733          0.6298%
3890 W. Northwest Hwy. Ste. 400
Dallas, TX 75220


THOMAS F. AUGUST                                 88,576          0.2123%
3890 W. Northwest Hwy. Ste. 400
Dallas, TX 75220

DENNIS J. DuBOIS                                 58,274          0.1397%
3890 W. Northwest Hwy. Ste. 400
Dallas, TX 75220

RICHARD J. BRADSHAW, JR.                          6,984          0.0167%
1828 Mt. Paran Rd.
Atlanta, GA 30327

PRENTISS CREDIT SHELTER TRUST                   333,387          0.7992%
3890 W. Northwest Hwy. Ste. 400
Dallas, TX 75220

PETER O. HAUSMANN                               155,257          0.3722%
1160 W. Swedesford Rd., Ste. 140
Berwyn, PA 19312

BT ALEX BROWN Exchange Fund, L.P.                36,867          0.0884%
1 South Street, 18th Floor
Baltimore, MD 21202

HENRY C. GULBRANDSEN, JR.                       133,720          0.3205%
1160 W. Swedesford Rd., Ste. 140
Berwyn, PA 19312

TIMOTHY J. WEBER                                133,720          0.3205%
1160 W. Swedesford Rd., Ste. 140
Berwyn, PA 19312
</TABLE>
<PAGE>
<TABLE>
        Partner                              Partnership      Percentage
                                               Units           Interest
<S>                                          <C>              <C>
STEVEN A. STATTNER                               30,078          0.0721%
1160 W. Swedesford Rd., Ste. 140
Berwyn, PA 19312

THE F M (BRUCE) BRUSSEAU TRUST                   16,735          0.0401%
5050 Avenida Encinas, Ste. 350
Carlsbad, CA 92008

NEWPORT NATIONAL CORPORATION                     40,078          0.0961%
5050 Avenida Encinas, Ste. 350
Carlsbad, CA 92008

SCOTT R. BRUSSEAU                                15,049          0.0361%
5050 Avenida Encinas, Ste. 350
Carlsbad, CA 92008

JEFFREY A. BRUSSEAU                              13,962          0.0335%
5050 Avenida Encinas, Ste. 350
Carlsbad, CA 92008

ELLIOTT INVESTMENT COMPANY, L.P.                  9,514          0.0228%
5000 Burch Street, Suite 6200
Newport Beach, CA 93660

D. KENT DAHLKE                                      632          0.0015%
4695 MacArthur Court, Suite 1100
Newport Beach, CA 92660

JACOB BROUWER & JEANETTE BROUWER TRUST          144,980          0.3475%
1508 West Mission Rd.
Escondido, CA 92029

KENNETH L. HATFIELD                              93,860          0.2250%
17627 Kaman Road
Cypress, TX 77429

MICHAEL G. TOMBARI                               93,860          0.2250%
5811 Redwood River Drive
Kingwood, TX 77345

JAMES J. GORMAN                                  10,063          0.0241%
120 Arrandale Blvd.
Exton, PA 19341

CHRISTOPHER J. KNAUER                            10,063          0.0241%
120 Arrandale Blvd.
Exton, PA 19341

TOTAL                                        41,717,041        100.0000%
</TABLE>

                                      2
<PAGE>
<TABLE>
        Partner                              Partnership      Percentage
                                               Units           Interest
<S>                                          <C>              <C>
Series A Cumulative Preferred Shares
------------------------------------

Limited Partners:

PRENTISS PROPERTIES TRUST (Security Capital)  3,773,585        100.0000%
3890 W. Northwest Hwy. Ste. 400
Dallas, TX 75220

TOTAL                                         3,773,585        100.0000%


Series B Cumulative Redeemable Perpetual Preferred Units
--------------------------------------------------------

Limited Partners:

ARGOSY REALTY CORPORATION                        36,464          1.9191%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109

BELMAR REALTY CORPORATION                        36,464          1.9191%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109

BELPORT REALTY CORPORATION                       36,464          1.9191%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109

BELRIEVE REALTY CORPORATION                      36,464          1.9191%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109

BELAIR REAL ESTATE CORPORATION                  539,144         28.3761%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109

BELCREST REALTY CORPORATION                   1,215,000         63.9475%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109
</TABLE>
                                       3
<PAGE>
<TABLE>
<S>                                          <C>              <C>
TOTAL                                         1,900,000        100.0000%

Series C Cumulative Redeemable Perpetual Preferred Shares
---------------------------------------------------------

Limited Partners:

BELCREST REALTY CORPORATION                   1,400,000        70.0000%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109

BELAIR REAL ESTATE CORPORATION                  600,000         30.0000%
c/o Eaton Vance Management
The Eaton Vance Building
255 State Street
Boston, MA 02109

TOTAL                                         2,000,000        100.0000%
</TABLE>

                           [SIGNATURE PAGE FOLLOWS]

                                       3
<PAGE>
Acknowledged:
Prentiss Properties I, Inc
General Partner

By: /s/ Gregory S. Imhoff
   ----------------------
   Gregory S. Imhoff
   Secretary

                                       4