EXECUTION COPY

     MASTER AGREEMENT

     Master Agreement, dated as of October 3, 2005 (this “Agreement”), by and
between Brandywine Operating Partnership, L.P., a Delaware limited partnership
(“Brandywine”), and The Prudential Insurance Company of America, a New Jersey
corporation (“Prudential”).

     Background

     On the date hereof, Brandywine, Brandywine Realty Trust, a Maryland real
estate investment trust (“Parent”), Brandywine Cognac I, LLC, a Maryland limited
liability company (“Merger Sub”), Brandywine Cognac II, LLC, a Delaware limited
liability company (“L.P. Merger Sub”), Prentiss Properties Trust, a Maryland
real estate investment trust (the “Company”), and Prentiss Properties
Acquisition Partners, L.P., a Delaware limited partnership (“Company L.P.”),
have executed and delivered an Agreement and Plan of Merger (the “Merger
Agreement”). Terms used herein as defined terms but not defined herein have the
meanings assigned to them in the Merger Agreement.

     On the date hereof, Prudential, the Company and Company L.P. have executed
and delivered the Prudential Asset Purchase Agreement attached hereto as Exhibit
A (the “Prudential Asset Purchase Agreement”).

     Brandywine and Prudential desire to enter into this agreement to, among
other things, set forth the terms under which Prudential will acquire the
Specified Assets (x) from Company L.P. or one or more Company Subsidiaries
pursuant to the Prudential Asset Purchase Agreement on the business day prior to
the Closing Date as more particularly provided herein and in the Merger
Agreement or (y) from Merger Sub pursuant to the Alternative Asset Purchase
Agreement (as defined herein) immediately following the OP Effective Time as
more particularly provided herein and in the Merger Agreement. The terms
“Specified Assets” and “Joint Venture Owned Property” shall have the meanings
given to them in the Prudential Asset Purchase Agreement.

     NOW, THEREFORE, intending to be legally bound, the parties agree as
follows:

     1.      Acquisition of Specified Assets.

               a.     In the event that Prudential is obligated to consummate
the Prudential Asset Purchase Agreement pursuant to Article X of the Merger
Agreement, then Prudential agrees to perform or cause to be performed all of its
and the Transferees’ (defined below) obligations thereunder.

               b.     In the event that the Closing is scheduled to occur under
the Merger Agreement and Prudential, Company L.P. and Prentiss Properties Real
Estate Fund I, L.P. are not required to consummate the transactions described in
the Prudential Asset Purchase Agreement pursuant to Article X of the Merger
Agreement, then (1) Prudential shall cause the Transferees to make a capital
contribution to Merger Sub in immediately available funds in the aggregate
amount of the Specified Assets Purchase Price by noon Eastern Time on the
Closing Date, (2) Brandywine and Prudential shall enter into an asset purchase
agreement, substantially in the form attached hereto as Exhibit B (the
“Alternative Asset Purchase Agreement”), and (3) simultaneously with the
Closing, Brandywine will cause the Specified Assets to be transferred and
conveyed to Prudential or the Transferees in exchange for the transfer to
Company L.P. of the interest of Prudential and the Transferees in Merger Sub.
The term “Specified Assets Purchase Price” means $747,650,417, subject to
adjustment as provided herein and less the outstanding balance of any
indebtedness on any of the Specified Assets (including the Joint Venture Owned
Property) that is not repaid in full on or before the Closing date.

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               c.      Prudential shall pay all state and local transfer and
similar taxes and fees (the “Transfer Taxes”) associated with the transfer of
the Specified Assets pursuant to the Merger Agreement, the Prudential Purchase
Agreement, the Alternative Asset Purchase Agreement and this Agreement, as
applicable; provided, however, that in the event that Prudential and/or a
Transferee acquires the Specified Assets pursuant to Paragraph 1.b and the
Transfer Taxes associated therewith are higher than they would have been if
Prudential had acquired the Specified Assets pursuant to the Prudential Asset
Purchase Agreement, then Brandywine shall pay Prudential at Closing the amount
of the excess.

               d.      Brandywine acknowledges that Prudential shall have the
right to assign all or any portion of the rights and obligations of Prudential
under this Agreement to one (1) or more entities designated by it (each, a
“Transferee”). No such assignment shall release Prudential from its obligations
under this Agreement.

               e.      Without limiting the terms of Section 16, Prudential, on
behalf of each Transferee, agrees that neither Brandywine nor any Affiliate of
Brandywine shall have any liability to Prudential or to any Transferee for any
of the representations, warranties or covenants of the Company or Company L.P.
contained in the Merger Agreement. However, Brandywine agrees, if requested by
Prudential and at Prudential’s cost and expense, to enforce Brandywine’s rights
under the Merger Agreement with respect to any misrepresentations or breaches of
covenants that have resulted in loss, cost or expense to Prudential and to
cooperate with Prudential in all reasonable respects with respect to any such
enforcement.

     2.      Management and Leasing Agreement.     On the Final Condition
Satisfaction Date (in the event that Prudential and/or a transferee acquires the
Specified Assets pursuant to Paragraph 1(a)) and otherwise on the Closing Date,
each Transferee and BTRS, Inc., an Affiliate of Brandywine, shall execute and
deliver a Leasing and Management Agreement in substantially the form attached
hereto as Exhibit C and Brandywine shall cause the existing property management
agreements for the Specified Assets to be terminated.

     3.      Prudential Payments.

               a.      At the REIT Effective Time, Prudential agrees to pay to
Brandywine, or its assignee, One Million Dollars ($1,000,000) in immediately
available funds to be used to pay a portion of the fees owing by Brandywine to
J.P. Morgan Securities Inc. in connection with the transactions contemplated by
the Merger Agreement.

               b.      At the REIT Effective Time, Prudential agrees to pay to
Brandywine Four Million Dollars ($4,000,000) in immediately available funds on
account of severance costs that Brandywine will incur in connection with the
transactions contemplated by the Merger Agreement.

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     4.     Authority Under Merger Agreement.

               a.      None of Brandywine, Parent, Merger Sub, L.P. Merger Sub
or any Affiliate of any of them (collectively, the “BDN Parties”) shall amend
the Merger Agreement in any way without in each instance obtaining the prior
written consent of Prudential, which consent shall not be unreasonably withheld
or delayed.

               b.      None of the BDN Parties shall grant or withhold any
consent or approval under or in connection with the Merger Agreement, or
authorize, commit to or agree to any matter in connection with the Merger
Agreement, without in each instance obtaining the prior written consent of
Prudential, which consent shall not be unreasonably withheld or delayed. Without
limiting the foregoing, the terms of this Paragraph 4.b shall apply to (i) any
changes in the structure of the transactions contemplated by the Merger
Agreement requested pursuant to Section 1.10 of the Merger Agreement and (ii)
any matters for which consent of Parent is required under Section 5.01 of the
Merger Agreement.

               c.      None of the BDN Parties shall waive any of its conditions
to Closing without in each instance obtaining the prior written consent of
Prudential, which consent shall not be unreasonably withheld or delayed.

               d.      No BDN Party shall exercise any right or remedy under the
Merger Agreement, including, without limitation, any termination or extension
right, without in each instance obtaining the prior written consent of
Prudential, which consent shall not be unreasonably withheld or delayed.

               e.      In any instance where the consent or approval of
Prudential is requested under this Agreement, Prudential will use commercially
reasonable efforts to respond to Brandywine within two (2) business days after
Brandywine’s request for consent or approval has been submitted to Prudential.

     5.      Property Diligence and Sharing of Remediation Expenses.

               a.      Each of Brandywine and Prudential will have until October
20, 2005 (the “Due Diligence Period”) to conduct, at its sole cost and expense
(subject to the other terms of this Agreement) diligence on the Company
Properties allocated to it (i.e., the Specified Assets, in the case of
Prudential, and the other Company Properties, in the case of Brandywine). For
purposes of this Paragraph 5, the diligence of Brandywine and Prudential will be
limited to title, survey, zoning, permitting and land use, structural and
environmental diligence (i.e., leases, rent rolls and tenant credit would not be
subject to diligence for purposes of this Paragraph 5) (such permitted due
diligence matters, collectively, the “Permitted Due Diligence”). Any such
diligence or activities shall be conducted in the manner permitted by Section
6.02 of the Merger Agreement.

               b.      Each of Brandywine and Prudential, on behalf of the
Transferees, agrees to fund a portion of the Eligible Remediation Costs (defined
below) for the Company Properties to be acquired by the other. The aggregate
maximum amount that Brandywine shall be obligated to pay to Prudential on
account of Eligible Remediation Costs (net of any payments made by Prudential to
Brandywine on account of Eligible Remediation Costs) is $18,750,000. The
aggregate maximum amount that Prudential shall be obligated to pay to Brandywine
on account of Eligible Remediation Costs (net of any payments made by Brandywine
to Prudential on account of Eligible Remediation Costs) is $6,250,000.

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               c.      Neither Brandywine nor Prudential shall have any
obligation to make a payment to the other on account of Eligible Remediation
Costs for a Company Property to be acquired by the other unless the aggregate
amount of Eligible Remediation Costs for such Company Property exceeds ten
percent (10%) of the Allocated Value (defined below) of such Company Property.
If the aggregate amount of Eligible Remediation Costs for such Company Property
exceeds ten percent (10%) of the Allocated Value of such Company Property, then
(i) if such Company Property is to be acquired by Brandywine, Prudential will
pay to Brandywine an amount equal to the Prudential Percentage multiplied by the
amount of such excess over ten percent (10%) of the Allocated Value (subject to
the above aggregate $6,250,000 cap) and (ii) if such Company Property is to be
acquired by a Transferee, Brandywine will pay to Prudential an amount equal to
the Brandywine Percentage (as defined below) multiplied by the amount of such
excess over ten percent (10%) of the Allocated Value (subject to the above
aggregate $18,750,000 cap). The “Allocated Value” of a Company Property is the
dollar amount allocated to such Company Property as set forth on Exhibit D
hereto.

               d.      Notwithstanding the foregoing, if the aggregate amount of
Eligible Remediation Costs for a Company Property to be acquired by a Transferee
exceeds ten percent (10%) of the Allocated Value of such Company Property, then,
if such Company Property is not an Excluded Property (defined below), Prudential
shall have the right, on behalf of the applicable Transferee, in Prudential’s
sole and absolute discretion, to elect either (i) to drop such Company Property
(i.e., not acquire such Company Property), or (ii) to cause the applicable
Transferee to acquire a Substitute Property (defined below) in lieu of such
Company Property. If Prudential elects to drop a Company Property (such Company
Property, a “Dropped Property”), it shall receive a credit against the Specified
Assets Purchase Price in an amount equal to (x) the Allocated Value for such
Dropped Property minus (y) the Prudential Percentage of all of the Eligible
Remediation Costs for such Dropped Property. Any such election must be made by
Prudential within fifteen (15) days following expiration of the Due Diligence
Period. In no event may Prudential elect to drop or substitute Company
Properties that have an aggregate Allocated Value in excess of $150,000,000 (the
“$150,000,000 Limit”). In addition, in no event may Prudential elect to drop or
substitute a Company Property if Brandywine elects to pay to Prudential the
amount by which Eligible Remediation Costs for such Company Property exceed ten
percent (10%) of the Allocated Value of such Company Property. Any such election
must be made by Brandywine no later than the later of (x) the fifteenth (15th)
day after expiration of the fifteen (15) day period referred to above in this
Paragraph 5.d and (y) the fifteenth (15th) day after agreement of Brandywine and
Prudential as to, or other determination as provided in Paragraph 6 below of,
the Eligible Remediation Costs of the applicable Company Property, and all such
Eligible Remediation Costs shall be paid to Prudential on the Closing Date. Each
of the Company Properties identified on Exhibit E-1 is an “Excluded Property.”
In addition to the right of Prudential to elect to drop or cause a substitution
of a Company Property that is not an Excluded Property, as provided in this
Paragraph 5.d, Prudential may elect to drop any “development property”
identified on Exhibit E-2 if Prudential, in its reasonable discretion, is not
satisfied with the development potential or the status of land use permits and
approvals for such development property. In order to exercise this right with
respect to a development property, Prudential must make such an election on or
before 5:00 p.m. on October 20, 2005, and in the event that Prudential makes
such an election, it will receive a credit against the Specified Assets Purchase
Price in an amount equal to the Allocated Value for such dropped development
property or properties, and the Allocated Value attributable to such dropped
development property or properties shall not count against the $150,000,000
Limit.

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               e.      Within fifteen (15) days after the date of this
Agreement, Brandywine and Prudential will act in good faith to identify a group
of Company Properties which are eligible for exchange in accordance with, and
subject to, Section 5(d)(ii) each, a “Substitute Property”); provided that in
the event that Prudential, during the thirty (30)-day period (the “Substitute
Property Due Diligence Period”) that commences at the expiration of the
foregoing fifteen day period, identifies, through Permitted Due Diligence,
Eligible Remediation Costs in respect of any of such Substitute Properties in an
amount that exceeds, in respect of any given Substitute Property, ten percent
(10%) of the Allocated Value of such Substitute Property, then Prudential may
remove such Substitute Property from the pool of Substitute Properties.
Prudential may exercise its right to acquire a Substitute Property in lieu of a
Company Property only if the Company Property has an Allocated Value that is
within 10% of the Allocated Value of the Substitute Property. Any such election
by Prudential must be made by Prudential within fifteen (15) days following
expiration of the Substitute Due Diligence Period, and, for clarity, will be
subject to the right of Brandywine to override such election, as provided in
Paragraph 5.d, if Brandywine elects to pay to Prudential the amount by which
Eligible Remediation Costs for such Company Property exceeds ten percent (10%)
of the Allocated Value of such Company Property. Any such election must be made
by Brandywine no later than the later of (x) the fifteenth (15th) day after
expiration of the fifteen (15) day period referred to in the immediately
preceding sentence and (y) the fifteenth (15th) day after agreement of
Brandywine and Prudential as to, or other determination as provided in Paragraph
6 below of, the Eligible Remediation Costs of the applicable Company Property.
If all of the Substitute Properties exchanged pursuant to this Section 5.e have
a lower Allocated Value in the aggregate than the Company Properties for which
they were exchanged, the Contribution Amount will be decreased by an amount
equal to the difference between the aggregate Allocated Values of such Company
Properties and the Substitute Properties. If all of Substitute Properties
exchanged pursuant to this Section 5.e have a higher Allocated Value in the
aggregate than the Company Properties for which they were exchanged, the
Contribution Amount will be increased by an amount equal to the difference
between the aggregate Allocated Values of such Company Properties and the
Substitute Properties.

               f.      If either Brandywine or Prudential identifies costs that
it believes qualify as Eligible Remediation Costs, Brandywine or Prudential, as
applicable, will provide to the other, no later than five (5) days following
expiration of the Due Diligence Period, a reasonably detailed description of the
cost and reason why Brandywine or Prudential, as applicable, believes the cost
so qualifies. The parties will cooperate reasonably and in good faith to resolve
any disagreements as to the amount and qualification of any such costs, and any
disagreements that are not resolved by the parties by the fifteenth (15th) day
following expiration of the Due Diligence Period shall be determined in
accordance with Paragraph 6 below.

               g.      A cost will constitute an “Eligible Remediation Cost”
only if (i) the cost relates to removal of, or diminution in the value of a
Company Property on account of, an Encumbrance, any other title exception, or
any other matter shown on a survey, including, without limitation, any
encroachment, in each case that would have a material adverse effect on either
(x) the value of the applicable Company Property or (y) its ability to be used
for its intended purposes, or (ii) the cost relates to a structural problem at a
Company Property that is not in the nature of preventative maintenance and that
an owner of a property of a comparable quality would, in the exercise of
reasonable and prudent judgment, repair within one year following the date of
this Agreement, or (iii) the cost would reasonably be incurred to remediate an
environmental condition in, on or about a Company Property that an institutional
lender would reasonably require to be remediated, including, without limitation,
any such condition posing a threat to the well-being, value or safety of any
person or property, or (iv) the cost relates to the curing of any zoning or land
use violation affecting a Company Property, or to obtaining any permit, license
or approval from a governmental agency relating to the land use, construction or
occupancy of a Company Property, which, in each case, if not cured or obtained,
would have an adverse effect on (x) the value of the applicable Company Property
or (y) its ability to be used for its intended purposes.

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               h.      Brandywine and Prudential, on behalf of the Transferees,
shall each defend, indemnify, and hold the other harmless on account of any
claims, actions, losses, liabilities, damages, costs and expenses, whether
arising out of injury or death to persons or damage to any real or personal
property, including any property of tenants at Company Properties or otherwise
and including but not limited to, reasonable attorneys’ fees and costs incurred,
suffered by, or claimed against the other caused by the entry by Brandywine or
Prudential (as applicable) or any of its respective representatives upon a
Company Property or in carrying out any of its due diligence activities.

     6.      The parties shall attempt in good faith to resolve any dispute over
the amount or qualification of a cost as an Eligible Remediation Cost (a
“Dispute”) within ten (10) days from the date that one party notifies the other
in writing of the Dispute. In the event that the parties are unable to resolve
such Dispute within this ten day period, either party may, within ten (10) days
of the expiration of the initial ten (10) day period, notify the other party
that the Dispute shall be finally settled under the Commercial Arbitration Rules
of the AAA (or any similar successor rules thereto) as are in force on the date
when a notice of arbitration is received and such party may initiate such
process. The AAA shall propose arbitrator(s) that are, to the extent reasonably
possible, experts in the subject matter of the Dispute. The number of
arbitrators shall be three (3) unless Brandywine and Prudential agree to one (1)
within five (5) days within the receipt of the written notice of the Dispute.
The AAA shall provide, upon a party’s request, a list of ten (10) proposed
arbitrators, and each of Brandywine and Prudential shall pick one (1) arbitrator
from such list within five (5) days within the receipt of such list and the
arbitrators so selected shall pick a third arbitrator from such list within five
(5) days of the selection of these two arbitrators. The arbitration proceedings
shall be conducted in New York, New York. For clarity, the pendency of an
arbitration proceeding shall not limit the obligations of Brandywine or
Prudential to proceed with the consummation of the transactions provided for in
this Agreement or in the Prudential Asset Purchase Agreement; provided, however,
that Prudential at its election shall not be obligated to take or cause a
Transferee to take title to any Company Property that is subject to a Dispute.

     7.      Material Adverse Change Following Due Diligence Period.  If, following the expiration of the Due Diligence Period and prior to the Final Notice Date (defined below), a change occurs to a Specified Asset and such post-Due Diligence Period change relates to a subject matter of the Permitted Due Diligence and the post-Due Diligence change (if it had occurred prior to the expiration of the Due Diligence Period) would have given rise to an Eligible Remediation Cost, then the terms of Paragraph 5 of this Agreement shall apply just as if such change had occurred and been known and objected to by Prudential during the Due Diligence Period in accordance with the terms of this Agreement; provided that any Eligible Remediation Cost attributable to such post-Due Diligence Period change shall be subject to a new ten percent (10%) threshold that is separate and apart from (and not aggregated with) the ten percent (10%) threshold applicable to Eligible Remediation Costs identified in the Due Diligence Period; and provided further that the right of Prudential in Paragraph 5.d and this Paragraph 7 to elect to drop a Specified Asset or substitute a Company Property, on and subject to the terms and conditions set forth therein and herein, may not be exercised after the Final Notice Date.  The “Final Notice Date” is the fifteenth (15th) day prior to the scheduled date of the Parent Shareholders Meeting.  For clarity, any Specified Asset or Company Properties that Prudential may elect to drop or substitute, as the case may be, under this paragraph 7 or under Paragraph 5.d shall be subject to the single (aggregate) $150,000,000 Limit except as otherwise expressly provided with respect to dropped development properties and the Membership Interest (defined below).

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     8.      Expenses and Expense Recoveries; Other Receipts Under Merger
Agreement.

               a.      The parties agree to be solely responsible for their
respective legal and other expenses attributable to the negotiation and
preparation of this Agreement and the Prudential Asset Purchase Agreement.

               b.      In the event that the Merger Agreement is terminated and
Brandywine receives payment of the Termination Fee or the Alternate Fee, then
the Termination Fee or the Alternate Fee received by Brandywine, minus any
portion of the Termination Fee or the Alternate Fee that Brandywine is obligated
to pay to Parent Financial Advisor, shall be split between Brandywine and
Prudential as follows: Brandywine shall be entitled to the Brandywine Percentage
(defined below) and Prudential shall be entitled to the Prudential Percentage
(defined below). The “Brandywine Percentage” shall equal (i) the aggregate of
all of the Allocated Values for the Company Properties, minus the aggregate of
all of the Allocated Values of all of the Specified Assets (excluding any
Dropped Properties), divided by (ii) the aggregate of all of the Allocated
Values for the Company Properties. The Prudential Percentage shall equal 1.0
minus the Brandywine Percentage (the “Prudential Percentage”). If Brandywine is
entitled to be reimbursed for its Expenses pursuant to the terms of the Merger
Agreement, any amount of such Expenses that remains after Brandywine pays any
and all required fees to Parent Financial Advisor shall be allocated between
Brandywine and Prudential in accordance with the Prudential Percentage and
Brandywine Percentage; provided, however, that neither Brandywine nor Prudential
shall be entitled to a portion of the Expenses that exceeds such party’s out of
pocket expenses.

               c.      Brandywine hereby agrees to indemnify, defend and hold
Prudential and the Transferees harmless from and against any and all loss,
liability, cost, claim, damage and expense (each, a “Loss”), including, without
limitation, reasonable attorney’s fees, suffered or incurred by Prudential or
any Transferee at any time in connection with the existence and terms of any Tax
Protection Arrangements, but this agreement (except as provided in Paragraph
8(e)) shall not be construed to apply to any tax matters that arise under the
joint venture asset included in the Specified Assets known as “Prentiss/Collins
del Mar Heights, LLC”. This provision 9.c shall survive Closing and not be
merged therein.

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               d.      Brandywine hereby agrees to indemnify, defend and hold
Prudential and the Transferees harmless from and against any and all Loss
suffered or incurred by Prudential or any Transferee on account of its having
held in interest in Merger Sub or any other subsidiary or Affiliate of
Brandywine. This provision 9.d shall survive Closing and not be merged therein.

               e.      Brandywine hereby agrees to indemnify, defend and hold
Prudential and the Transferees harmless from and against any and all Loss
suffered or incurred by Prudential or any Transferee pursuant to Section 8.6 of
the Operating Agreement of Prentiss/Collins Del Mar Heights, LLC. and this
agreement shall survive Closing and not be merged therein.

               f.      Brandywine hereby agrees to indemnify and hold harmless
Prudential and the Transferees from and against all liability and cost
(including reasonable attorneys’ fees) incurred by reason of claims against
Prudential and the Transferees relating to Space Leases or the proceeds under
Space Leases arising from or relating to the period prior to the date of Closing
in respect of Company Properties acquired by Prudential or a Transferee.
Prudential hereby agrees to indemnify and hold harmless Brandywine and Company
L.P. from and against all liability and cost (including reasonable attorneys’
fees) incurred by reason of claims against Brandywine or Company L.P. relating
to the Space Leases or the proceeds under Space Leases arising from or relating
to the period from and after the date of Closing in respect of Company
Properties acquired by Prudential or a Transferee. The agreements in this
Paragraph 8(f) shall survive Closing and not be merged therein.

     9.      Company Property Substitutions. In the event Prudential elects to
acquire a Substitute Property pursuant to Paragraphs 5 and 7 above, such
Substitute Property shall become a Specified Asset under the Merger Agreement,
the Prudential Asset Purchase Agreement, the Alternative Asset Purchase
Agreement and this Agreement for all purposes thereunder and hereunder.

     10.      In the event that Collins Corporate Center, LLC does not consent
in writing, prior to the fifth (5th) day prior to the scheduled Closing Date, to
the acquisition by Prudential or a Transferee of the membership interest (the
“Membership Interest”) of Company L.P. in the limited liability company known as
“Prentiss/Collins Del Mar Heights, LLC (the “Del Mar LLC”), and acknowledge the
right of Prudential or such Transferee to hold the position of “Managing Member”
under the Operating Agreement dated as of December 17, 2001 of Del Mar LLC (the
“Del Mar Operating Agreement”), then Prudential may, by 5:00 p.m. on the day
prior to the Final Condition Satisfaction Date or Closing Date, as applicable,
elect to drop its acquisition of the Membership Interest, in which case neither
Prudential nor any Transferee shall acquire the Membership Interest and
Prudential will receive a credit against the Specified Assets Purchase Price in
an amount equal to the Allocated Value for the Membership Interest. The
Allocated Value attributable to such dropped Membership Interest shall not count
against the $150,000,000 Limit.

     11.      Representations and Warranties of Brandywine. Brandywine hereby
represents and warrants to Prudential and the Transferees as of the date hereof
and as of Closing as follows:

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               a.      Brandywine is a limited partnership duly formed and
validly existing under the laws of the State of Delaware, has full limited
partnership power and authority to own its properties and to carry on its
business as now conducted, and is duly qualified or licensed to do business and
is in good standing in each jurisdiction in which the nature of the business it
is conducting, or the ownership, operation or leasing of its properties or the
management of properties for others makes such qualification or licensing
necessary, except where the failure to be so qualified or licensed or in good
standing would not reasonably be expected, individually or in the aggregate, to
have a material adverse effect.

               b.      Brandywine has full power and authority to enter into
this Agreement and to consummate the transactions contemplated herein. This
Agreement has been duly executed and delivered by Brandywine and is a valid and
legally binding obligation of Brandywine, enforceable against Brandywine in
accordance with its terms.

               c.      Neither the execution, delivery and performance of this
Agreement, nor the consummation of the transactions contemplated herein, will
constitute or cause a breach, default or violation of (i) the charter documents
or bylaws of Brandywine or (ii) any contract to which Brandywine is a party.

               d.      Brandywine has not made any agreement or taken any action
which may cause anyone claiming through Brandywine to become entitled to a
commission as a result of the transactions contemplated pursuant to this
Agreement (except for claims which would be made solely against Brandywine).

               e.      Set forth in Section 3.7(b) of the Company Disclosure
Letter is a list of all indebtedness affecting any Fee Owned Property (as
defined in the Prudential Asset Purchase Agreement) or the Joint Venture Owned
Property (as defined in the Prudential Asset Purchase Agreement), in each case
that will not be repaid in full by the Company, the applicable Property Owner or
the owner of the Joint Venture Owned Property, as the case may be, at its sole
cost and expense on or before the Specified Assets Closing Date (as defined in
the Prudential Asset Purchase Agreement) (collectively, the “Outstanding
Indebtedness”). The Outstanding Indebtedness is free from default. Except for
the Outstanding Indebtedness listed the Company Disclosure Letter and the
schedules attached thereto, (the “Consent Required Outstanding Indebtedeness”),
the Outstanding Indebtedness may be assumed by each applicable Transferee
without the consent of any party thereto and without payment of any fee or other
amount to the holder thereof or any other party.

               f.      None of Company L.P. or any of its Affiliates has
transferred or permitted the transfer of any interest in a Fee Owned Property or
has granted any person or entity the right or option to acquire any interest in
any Fee Owned Property other than as set forth the Company Disclosure Letter and
the schedules attached thereto. None of Company L.P. or any of its Affiliates
has created, voluntarily or otherwise, or permitted the creation, voluntarily or
otherwise, of any lien or encumbrance on any Fee Owned Property or the Joint
Venture Owned Property, other than the Permitted Encumbrances (as defined in the
Merger Agreement) and as set forth in the Company Disclosure Letter and the
schedules attached thereto.

               g.      None of Company L.P. or any of its Affiliates has
transferred any interest in, other otherwise encumbered or permitted the
encumbrance of, all or any portion of the Joint Venture Interest, and the Joint
Venture Interest is owned by the Joint Venture Interest Owner free and clear of
any right, claim, warrant, option, lien or other interest or encumbrance of any
nature whatsoever except as set forth in the Operating Agreement dated as of
December 17, 2001 (the “Del Mar Operating Agreement”) between Company L.P. and
Collins Corporate Center, LLC.

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               h.      There are no leasing or similar commissions due in
connection with any Space Lease affecting any of the Specified Assets, other
than such market-rate commissions as may become due after the date hereof for
expansions and renewals pursuant to written agreements provided to Prudential on
or before the date hereof.

               i.      Company L.P. has made available to Prudential all
material contracts affecting any Fee Owned Property or the Joint Venture Owned
Property or Joint Venture Interest (as defined in the Prudential Asset Purchase
Agreement). Company L.P. has delivered to Prudential a true, complete and
correct copy of the Del Mar Operating Agreement.

               j.      The Release and Settlement Agreement dated September 12,
1996 among Shell Oil Company, Cadillac Fairview/California, Inc., GP Holdings,
Inc. and The Prentiss/Copley Investment Group has not been modified and is in
full force and effect and free of default and constitutes the entire agreement
of the parties thereto on the subject covered thereby and Prudential will be a
“Successor Party” and not a “Cadillac Party.”

     12.      Representations and Warranties of Prudential. Prudential hereby
represents and warrants to Brandywine as follows (with such representations and
warranties applying to any Transferee):

               a.      Each Transferee is a limited liability company duly
formed and validly existing under the laws of the State of Delaware, has full
power and authority to own its properties and to carry on its business as now
conducted, and is duly qualified or licensed to do business and is in good
standing in each jurisdiction in which the nature of the business it is
conducting, or the ownership, operation or leasing of its properties or the
management of properties for others makes such qualification or licensing
necessary, except where the failure to be so qualified or licensed or in good
standing would not reasonably be expected, individually or in the aggregate, to
have a material adverse effect. Prudential is a corporation duly organized and
validly existing under the laws of the State of New Jersey, has full corporate
power and authority to own its properties and to carry on its business as now
conducted.

               b.      Each Transferee and Prudential has full power and
authority to enter into this Agreement and, if applicable, the Prudential Asset
Purchase Agreement and to consummate the transactions contemplated herein and,
if applicable, contemplated in the Prudential Asset Purchase Agreement. This
Agreement has been duly executed and delivered by Prudential and is a valid and
legally binding obligation of Prudential, enforceable against Prudential in
accordance with its terms and the Prudential Asset Purchase Agreement, if
executed and delivered pursuant to Article X of the Merger Agreement, will be a
valid and legally binding obligation of Prudential, enforceable against
Prudential in accordance with its terms.

               c.      Neither the execution, delivery and performance of this
Agreement and, if applicable, the Prudential Asset Purchase Agreement, nor the
consummation of the transactions contemplated herein or, if applicable, therein,
will constitute or cause a breach, default or violation of (i) the charter
documents (if applicable) of Prudential or any Transferee or (ii) any contract
to which Prudential or any Transferee is a party.

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               d.      Prudential has not made any agreement or taken any action
which may cause anyone claiming through Prudential to become entitled to a
commission as a result of the transactions contemplated pursuant to this
Agreement (except for claims which would be made solely against Prudential).

     13.      Prorations.

               a.      Ad valorem, personal property and similar taxes
(including assessments) for the then current tax period relating to the
Specified Assets and, to the extent of the Joint Venture Interest, the Joint
Venture Owned Property shall be prorated between the applicable Property Owner
or other owner and the applicable Transferee at the Specified Assets Closing as
of 11:59 p.m. on the day immediately preceding the Specified Assets Closing
Date. If the Specified Assets Closing occurs before the tax rate or assessed
valuation for a Specified Asset or the Joint Venture Owned Property, as the case
may be, is fixed for the then current tax year, apportionment of taxes and other
amounts hereunder shall be made on the basis of the tax rate for the preceding
year applied to the latest assessed respective valuation of the applicable
Specified Asset or the Joint Venture Owned Property, as applicable, and when the
tax rate and assessed valuations are fixed for the tax year in which the
Specified Assets Closing occurs, Company L.P. and the applicable Transferee
hereby agree to adjust the proration of taxes hereunder and, if necessary, to
refund or pay such sums to the other party as shall be necessary to effect such
adjustment.

               b.      All rents and other payments from tenants under the Space
Leases affecting the Specified Assets or Company L.P.’s or its Affiliate’s
interest in the Joint Venture Owned Property shall be prorated between the
applicable Property Owner and the applicable Transferee as of 11:59 p.m. on the
day immediately preceding the Specified Assets Closing Date. Each Property Owner
shall be entitled to all rents, charges, and other revenue of any kind
attributable to any period under the Space Leases affecting its Specified Assets
to, but not including, the Specified Assets Closing Date. Each Transferee of a
Fee Owned Property shall be entitled to all rents, charges and other revenue of
any kind attributable to any period under the Space Leases affecting its
Specified Assets on and after the Specified Assets Closing Date. The owner of
the Joint Venture Interest and the Transferee thereof shall prorate such rent,
charges and other revenue attributable to the Joint Venture Owned Property on a
similar basis in accordance with their interests. Rents or other reimbursements
due landlord under the Space Leases affecting Specified Assets not collected as
of the Specified Assets Closing Date shall not be prorated at the time of the
Specified Assets Closing, but each applicable Transferee shall make a good faith
effort (which shall not include bringing legal action against a tenant) to
collect the same on the applicable Owner’s behalf and to tender the same to
Company L.P. upon receipt (which obligation of such Transferee shall survive the
Closing and not be merged therein for a period of four (4) months); provided,
however, that all rents, escalations and other reimbursements due landlord under
the Space Leases affecting its Specified Assets collected by a Transferee on or
after the Specified Assets Closing Date, less the reasonable costs of
collection, shall first be applied to all amounts due under the Space Leases
affecting its Specified Assets at the time of collection (i.e., current rents
and sums due such Transferee as the current owner and landlord) with the balance
(if any) payable to Company L.P., but only to the extent of amounts delinquent
and actually due to Company L.P. The owner of the Joint Venture Interest and the
Transferee thereof shall treat rents and other reimbursements due landlord under
the Space Leases affecting the Joint Venture Owned Property on a similar basis
in accordance with their interests. At the Specified Assets Closing, each
applicable Transferee shall receive a credit for any obligations for brokerage
commissions or finders’ fees incurred in entering into any Space Leases
affecting any of its Specified Assets, or the Joint Venture Owned Property, as
the case may be, that was executed on or after the date of this Agreement.

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               c.      Operating expenses for the Specified Assets and the Joint
Venture Owned Property shall be prorated as of 11:59 p.m. on the day immediately
preceding the Specified Assets Closing Date. Each Property Owner shall pay all
utility charges and other operating expenses attributable to its Specified
Assets to, but not including, the Specified Assets Closing Date, and each
Transferee shall pay all utility charges and other operating expenses
attributable to its Specified Assets on or after the Specified Assets Closing
Date. The Joint Venture Interest Owner and its Transferee shall prorate utility
charges and operating expenses attributable to the Joint Venture Owned Property
on a similar basis in accordance with their interests. To the extent that the
amount of actual consumption of any utility services is not determined prior to
the Specified Assets Closing Date, a proration shall be made at the Specified
Assets Closing based on the last available reading and post-closing adjustments
between each Owner or the Joint Venture Interest Owner and the applicable
Transferee and thereafter a final proration shall be made within twenty (20)
days following the date that actual consumption for such pre-closing period is
determined, which obligation shall survive the Closing and not be merged
therein. No Property Owner shall assign to any Transferee any deposits which
such Property Owner has with any of the utility services or companies servicing
the Specified Assets. Each Transferee shall arrange with such services and
companies to have accounts opened in its name beginning at 12:01 a.m. on the
Specified Assets Closing Date.

     14.      Notices and Information under Merger Agreement. Brandywine agrees
to provide Prudential promptly with a copy of each notice received from or given
to any BDN Party under or pertaining to the Merger Agreement. Brandywine agrees
to keep Prudential fully informed as to the status of the transactions
contemplated by the Merger Agreement, the status of satisfaction of all
conditions to Closing, any Takeover Proposal and all information the BDN Parties
obtain with respect to the Specified Assets or the transactions contemplated by
the Merger Agreement or this Agreement. Brandywine agrees to consult with
Prudential with respect to portions of the Joint Proxy Statement/Prospectus that
relate to Prudential or the Specified Assets. Without limiting the foregoing or
any other term of this Agreement, Brandywine shall provide Prudential with
copies of all Partner Exchange Materials and all other correspondence related to
the foregoing and all notices given or received under Sections 6.03(c) or (d) of
the Merger Agreement.

     15.      Public Announcements      The parties acknowledge that the BDN
Parties will be required to make public disclosures, including filings with the
Securities and exchange Commission, in connection with the transactions
contemplated by this Agreement. BDN agrees to use good faith and commercially
reasonable efforts to afford Prudential an opportunity to review and comment on
press releases and public filings that reference Prudential or the transactions
contemplated by this Agreement prior to the public disclosure thereof.

     16.      Default or Failure of Condition Under Merger Agreement. If any BDN
Party breaches any term of the Merger Agreement (or fails to perform any
obligation of a BDN Party under the Merger Agreement required to be performed
prior to Closing, the performance of which is within any BDN Party’s exclusive
control, which, for the sake of clarity, does not include the failure to obtain
the Required Parent Vote), or if Parent fails to call or hold the Parent
Shareholders Meeting in accordance with Section 6.01 of the Merger Agreement and
as a result Prudential does not acquire the Specified Assets as contemplated by
this Agreement or the Prudential Asset Purchase Agreement, then each BDN Party
shall be jointly and severally liable to, and hereby agrees to indemnify,
Prudential for all of its actual out-of-pocket costs and expenses incurred in
connection with the Merger Agreement, the Prudential Asset Purchase Agreement,
this Agreement and the transactions contemplated by the Merger Agreement and
this Agreement, plus liquidated damages of $5,000,000. The parties hereto
acknowledge and agree that the damages suffered by Prudential as a result of
such a breach are difficult to determine and that the above-referenced amount as
a result is a reasonable approximation thereof. If Closing does not occur
because the Parent does not obtain the Required Parent Vote, then each BDN Party
shall be jointly and severally liable to, and hereby agrees to indemnify,
Prudential for all of its actual out-of-pocket costs and expenses incurred in
connection with the Merger Agreement, the Prudential Asset Purchase Agreement,
this Agreement and the transactions contemplated by the Merger Agreement and
this Agreement.

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     17.      Breach of Representation or Warranty under Merger Agreement. If
there exists any breach by Company or Company L.P. of any representation or
warranty in the Merger Agreement that pertains to any Specified Asset (other
than as to matter(s) that could reasonably have been identified by Prudential in
the course of its due diligence activities conducted prior to the Closing Date),
then, at any time within six (6) months following the Closing Date and assuming
the Closing is consummated, Prudential shall have the right to recover from
Brandywine its direct out of pocket expenses resulting from such breach, up to
an aggregate recovery of $5,000,000.

     18.      Loan Guarantees. If any guarantees of the Company or Company L.P.
or a Company Subsidiary of any loan that is secured by any of the Specified
Assets is not released on the Closing Date or Final Condition Satisfaction Date,
as applicable, then Prudential will indemnify the guarantor against any claims
that the applicable lender may assert under any such guaranty with respect to
any matter first arising after Closing.

     19.      Notices. All notices, requests and other communications required
or permitted to be given under this Agreement shall be in writing and shall be
delivered to a party either personally or by sending a copy thereof by first
class or express mail, postage prepaid, or by courier services, charges prepaid,
or by telecopier (with a copy sent by first class mail), to such party’s address
(or to such party’s telecopier number) as set forth below. Any such notice,
request or communication shall be deemed to be delivered, given and received for
all purposes of this Agreement (i) as of the date so delivered, if delivered
personally or by telecopy to the person entitled thereto, (ii) three (3)
business days after being deposited in the United States mail, if delivered by
first class or express mail, postage prepaid or (iii) one (1) business day after
being deposited with a telegraph office or courier service for delivery if
notice is sent by telegraph or courier services.

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     If to Brandywine:

     401 Plymouth Road
     Plymouth Meeting, PA 19462
     Attn: Gerard H. Sweeney, President and Chief Executive Officer
     Telecopier No.: (610) 832-4919

     With a copy to:

     401 Plymouth Road
     Plymouth Meeting, PA 19462
     Attn: Brad A. Molotsky, Senior Vice President and General Counsel
     Telecopier No.: (610) 832-4928

     and

     Pepper Hamilton LLP
     3000 Two Logan Square
     Philadelphia, PA 19103
     Attn: Michael H. Friedman, Esq.
     Telecopier No.: (215) 981-4750

     If to Prudential:

     c/o Prudential Real Estate Investors
     8 Campus Drive
     Parsippany, NJ 07054
     Attn: James P. Walker
     (973) 683-1690
     Telecopier No.: (973) 683-1752

     With a copy to:

     c/o Prudential Real Estate Investors
     8 Campus Drive
     Parsippany, NJ 07054
     Attn: Joan Hayden, Esq.
     (973) 683-1772
     Telecopier No.: (973) 683-1778
     
     and

     Goodwin Procter LLP
     Exchange Place
     Boston, MA 02109
     Attn: Minta E. Kay, P.C.
     (617) 570-1877
     Telecopier No.: (617) 523-1231

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     20.      Authorship; Advice of Counsel. Each of the parties has actively
participated in the negotiation and drafting of this Agreement, and each has
received independent legal advice from its attorney concerning this Agreement.
In the event of a dispute regarding this Agreement, the parties will be
conclusively deemed to be the joint authors of this Agreement, and no provision
of this Agreement will be interpreted against a party by reason of authorship.

     21.      Prevailing Party Reimbursement. In the event of any dispute
between or among the parties arising out of this Agreement resulting in any
litigation, the prevailing party in such litigation shall be entitled to recover
from the non-prevailing parties all reasonable out-of-pocket costs and expenses
in connection with such dispute.

     22.      Headings. The headings preceding the text of the Paragraphs of
this Agreement are inserted solely for convenience of reference and shall not
constitute a part of this Agreement or affect its meaning or construction.

     23.      Governing Law. This Agreement shall be construed in accordance
with, and governed in all respects by, the laws of the State of Delaware.

     24.      Amendments. This Agreement may not be amended or otherwise changed
in any respect whatsoever except by a writing signed by Brandywine and
Prudential.

     25.      Entire Agreement. This Agreement contains the entire agreement
between the parties concerning the subject matter hereof and supersedes any and
all prior or contemporaneous agreements, whether written or oral, concerning the
subject matter hereof.

     26.      Cooperation. The parties hereto agree to cooperate with each other
in all reasonable respects with respect to their obligations under this
Agreement and, if applicable, under the Prudential Asset Purchase Agreement and
consummation of the transactions contemplated thereby and hereby.

     27.      Binding Effect. This Agreement shall be binding upon and inure to
the benefit of the parties and their respective successors and assigns.

     28.      Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be deemed an original, and all of which
together shall constitute one instrument.

     29.      Facsimile. A facsimile copy of an original written signature shall
be deemed to have the same effect as an original written signature.

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     IN WITNESS THEREOF, this Agreement has been executed by Brandywine and
Prudential as of the day, month and year first above written.

  BRANDYWINE OPERATING PARTNERSHIP, L.P.       By:     Brandywine Realty Trust,
             its General Partner                  By: /s/ Gerard H.
Sweeney                        Name: Gerard H. Sweeney              Title:
President and Chief Executive Officer       THE PRUDENTIAL INSURANCE COMPANY OF
AMERICA,   a New Jersey corporation                  By: /s/  James P.
Walker                      Name:  James P. Walker              Title: Vice
President and Chief Executive Officer

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Exhibit A: Prudential Asset Purchase Agreement   Exhibit B: Form of Alternate
Asset Purchase Agreement   Exhibit C: Form of Leasing/Management Agreement  
Exhibit D: Property Allocated Value Schedule   Exhibit E-1: Excluded Property
Schedule   Exhibit E-2: Development Properties    

 

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