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                                                                    EXHIBIT 10.3

                                AGENCY AGREEMENT


     AGENCY AGREEMENT, dated as of March 2, 2001 (this "Agreement"), between
                                                        ---------
IMMUNEX REAL ESTATE TRUST 2001, a Delaware business trust (the "Lessor"), and
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IMMUNEX CORPORATION, a Washington corporation (the "Construction Agent").
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                              Preliminary Statement
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     A.  The Lessor and Lessee are parties to the Lease, pursuant to which
Lessee has agreed to lease the Property from the Lessor.


     B.  The Lessor and Lessee are also parties to that certain Participation
Agreement, dated as of the date hereof (as amended or otherwise modified from
time to time, the "Participation Agreement"), among Immunex Corporation, Immunex
                   -----------------------
Funding Corp., as SPC, Wilmington Trust Company, not in its individual capacity
except as set forth therein, but solely as Trustee, the Lessor, the financial
institutions listed on Schedule II thereto as Investors, the financial
institutions listed on Schedule I thereto as Banks, The Chase Manhattan Bank, as
Administrative Agent, Collateral Agent and Agent Bank.

     C.  Subject to the terms and conditions hereof, (i) the Lessor desires to
appoint the Construction Agent as its sole and exclusive agent in connection
with the acquisition of the construction of the Improvements in accordance with
the Plans and Specifications and (ii) the Construction Agent desires, for the
benefit of the Lessor, to cause the construction of the Improvements in
accordance with the Plans and Specifications as hereinafter set forth.

     NOW, THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto covenant and agree as follows:

                             SECTION 1. DEFINITIONS

     1.1 Defined Terms. Capitalized terms used and not defined herein shall have
     -----------------
the meanings assigned thereto in Annex A to the Participation Agreement; and the
rules of interpretation set forth in Annex A to the Participation Agreement
shall apply to this Agreement.
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                  SECTION 2. APPOINTMENT OF CONSTRUCTION AGENT

     2.1 Appointment and Acceptance. Subject to the terms and conditions hereof
     ------------------------------
and of the Participation Agreement and Lease, the Lessor hereby irrevocably
designates and appoints the Construction Agent as its exclusive agent in
connection with construction of the Improvements in accordance with the Plans
and Specifications. The Construction Agent hereby accepts the designation and
appointment as construction agent and agrees to perform such functions and
duties as set forth herein.

     2.2 Term.  This Agreement shall commence on the date hereof and shall
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terminate with respect to the Property upon the earlier to occur of:

          (i)   the Completion Date;

          (ii)  the termination of this Agreement pursuant to Section 5 hereof
     and the satisfaction by the Construction Agent of all obligations
     hereunder; and

          (iii) the exercise by the Construction Agent of the Purchase Option
     set forth in Section 20.1 of the Lease;

provided, however, that any termination of this Agreement shall not relieve the
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Construction Agent for liability for breach hereof.

     2.3 Scope of Authority. (a) The Lessor hereby expressly authorizes the
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Construction Agent to, and the Construction Agent shall, take all action
necessary or desirable for the construction of the Improvements in accordance
with the Plans and Specifications and the Budget and to fulfill all of the
obligations of the Construction Agent, including, without limitation:

          (i)   the right to approve payment of all invoices for services and
     materials related to the development, design, construction and equipping of
     the Improvements, and to submit Requisitions under the SPC Loan Agreement
     and the Participation Agreement and to receive the proceeds of Advances
     under the SPC Loan Agreement and to receive the same directly from the
     Administrative Agent provided, however, the Construction Agent shall not
                          --------  -------
     incur any expenses in excess of an amount equal to the sum of the SPC Loan
     Commitments plus the Investors Contribution Commitment without the express
     written consent of the Lessor;

          (ii)  all design and supervisory functions relating to the
     construction of the Improvements and performing all engineering work
     related to the construction of the Improvements;

          (iii) negotiating and entering into all contracts or arrangements for
     the construction of the Improvements, development of infrastructure
     relating thereto, and the procurement of the equipment necessary to
     construct the Improvements on such terms and conditions as are customary
     and reasonable in light of local standards and practices;

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          (iv)   obtaining all necessary permits, licenses, consents, approvals
     and other authorizations, including those required under applicable
     Environmental Laws, from all Governmental Authorities in connection with
     the development and construction of the Improvements substantially in
     accordance with the Plans and Specifications;

          (v)    maintaining all books and records with respect to the
     construction, operation and management of the Property;

          (vi)   contesting any mechanics' or materialmen's lien and
     prosecuting all other permitted contest rights of Lessee under Section 13.1
     of the Lease during the Construction Period;

          (vii)  performing those actions permitted to be performed by the
     Lessee under Section 12.2 of the Lease during the Construction Period;

          (viii) bringing or defending any claims or seeking resolution of any
     disputes arising from the Construction Agent's performance of the foregoing
     obligations;

          (ix)   performing any other acts necessary in connection with
     construction and development of the Improvements in accordance with the
     Plans and Specifications;

          (x)    submitting Requisitions to the Administrative Agent under the
     Participation Agreement and receiving the proceeds of Advances; and

          (xi)   maintaining the insurance required pursuant to Section 6
     hereof.

     (b)  Neither the Construction Agent nor any of its Affiliates or agents
shall, without the written consent of the Lessor, enter into any contract which
would, directly or indirectly, impose any liability or obligation on the Lessor,
any Bank or the Administrative Agent beyond the liability or obligations
permitted under the Operative Agreements, and each such contract shall be non-
recourse to Lessor, the Banks and the Administrative Agent in accordance with
Section 30.6 of the Lease.

     (c)  Subject to the terms and conditions of this Agreement, the
Construction Agent shall have sole management and control over the construction
means, methods, sequences and procedures with respect to the construction of the
Improvements.

     2.4  Delegation of Duties. The Construction Agent may execute any of its
     -------------------------
duties under this Agreement by or through agents, contractors, employees or
attorneys-in-fact and may enter into agreements with architects and contractors
for the purpose of so delegating such duties; provided that no such delegation
shall limit or reduce in any way the Construction Agent's duties and obligations
under this Agreement.

     2.5  Covenants of the Construction Agent. The Construction Agent hereby
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covenants and agrees that it will:

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     (a) cause construction of the Improvements to be prosecuted diligently and
continuously in accordance with the Plans and Specifications and in compliance
with all Legal Requirements and Insurance Requirements (except where the failure
to comply with Legal Requirements and Insurance Requirements is not material);

     (b) cause the Completion Date to occur on or prior to the Outside
Completion Date, free and clear (by removal or bonding) of Liens (other than
Permitted Liens or Lessor Liens) or material claims for materials supplied or
labor and services performed in connection with the construction of the
Improvements; provided, that the failure to cause the Completion Date to occur
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by the Outside Completion Date shall not be deemed a breach hereunder if such
delay is caused by a Force Majeure Event and Completion is accomplished within
three (3) months of the date otherwise applicable but for this proviso;
provided, further, to the extent such failure to complete is caused by a Force
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Majeure Event extending beyond such three (3) month period, the Construction
Agent shall elect one of the Construction Agent Options set forth in Section 2.6
and, if such election is not made within ten (10) Business Days of the end of
such three (3) month period, the Construction Agent shall be deemed to have
elected to purchase the Property for the Termination Value in accordance with
the provisions of Section 2.6;

     (c) notify the Lessor in writing not less than five (5) Business Days after
the Responsible Officer of the Construction Agent believes in his or her
reasonable judgment that the Completion of Construction will not occur on or
prior to the Outside Completion Date;

     (d) promptly notify the Lessor and the Administrative Agent in writing of
the occurrence of any Force Majeure Event and take all reasonable and practical
steps to minimize the disruption of the construction process arising from Force
Majeure Events;

     (e) comply in all respects with all Legal Requirements (including
Environmental Laws) and Insurance Requirements required for the Construction of
Improvements during the Construction Period;

     (f) procure, maintain and comply with all licenses, permits, orders,
approvals, consents, and other authorizations required for the construction of
the Improvements and provide information to the Lessor within a reasonable time
after the Lessor's request for such information regarding the status of the
foregoing;

     (g) subject to the limitations of Section 5.4(a) hereof and the receipt of
sufficient funds in accordance with Section 4.1 hereof, pay and discharge any
and all Project Costs, including, without limitation, the costs of, as
applicable, constructing, equipping and furnishing the Improvements and payment
of all real estate taxes, insurance premiums and other items payable prior to
Completion, as the same become due and payable;

     (h) following the Completion Date use reasonable good-faith efforts to
cause all outstanding punch list items with respect to the Improvements on the
Property to be completed, but in any event within three (3) months following the
Completion Date; and

     (i) comply fully and punctually with all of the material terms, covenants
and conditions on its part to be complied with under the agreements entered into
by Construction Agent pursuant to paragraph 2.3 (a) (iii) hereof.

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     2.6 Options. (a) After the Construction Agent gains knowledge or a
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reasonable expectation that the costs for construction of the Improvements shall
exceed the original Budget (or exceed the Budget as modified in accordance with
the Operative Agreements) or that Completion shall not occur on or prior to the
Outside Completion Date, the Construction Agent shall promptly (and in any event
within five (5) Business Days of gaining such knowledge or expectation) notify
the Administrative Agent in writing of the same. If at any time prior to the
Outside Completion Date, the Lessor shall have (x) determined in its reasonable
good faith judgment that (i) the sum of the available SPC Loan Commitment and
the available Investor Contribution Commitment shall be less than the amounts
necessary for Completion of the Improvements or (ii) Completion of the
Improvements shall not occur on or prior to the Outside Completion Date, or (y)
received any notice from the Construction Agent as referenced in the preceding
provisions of this paragraph, then in any such case Lessor shall have the option
to cease advancing Project Costs and/or replace the Construction Agent with a
new construction agent selected by the Lessor to finalize the Completion of the
Improvements. The cost and expense incurred to finalize the Completion of the
Improvements as referenced in the preceding sentence shall be the responsibility
of the Construction Agent and shall be payable by the Construction Agent on
demand; provided, in no event shall the obligations of the Construction Agent
for such costs and expenses exceed the amounts payable by the Construction Agent
under Section 5.4(a); provided, further, amounts expended by the Lessor to
finalize the Completion of the Improvements as referenced in the preceding
sentence shall be added to the Project Cost.

     (b) The costs of Completion of the Improvements in excess of the original
Budget (or the Budget as modified in accordance with the Operative Agreements)
in each case as previously delivered to the Lessor shall not be the
responsibility of the Construction Agent but instead shall be paid by Lessor, if
the Lessor so elects, from Advances made by SPC and the Investors to the extent,
but only to the extent, that (after taking into account such excess costs and
any other items of excess cost which are then known to the Construction Agent or
are reasonable for the Construction Agent to expect) the conditions precedent
set forth in Section 6.3 of the Participation Agreement are satisfied.

     (c) Subject to SPC and the Investors not agreeing to continue making
advances in accordance with the provisions of the next paragraph and in the
event from time to time (i) the Construction Agent gains knowledge or a
reasonable expectation that the costs of the Improvements shall exceed the
original Budget (or exceed the Budget as modified in accordance with the
Operative Agreements) or that Completion of the Improvements shall not occur on
or prior to the Outside Completion Date, or (ii) the Lessor shall have
determined in its reasonable good faith judgment that the sum of the available
SPC Loan Commitment and the available Investor Contribution Commitment shall be
less than the amounts necessary for Completion of the Improvements or that
Completion of the Improvements shall not occur on or prior to the Outside
Completion Date, the Construction Agent shall elect and comply (within ten (10)
days of the Construction Agent gaining such knowledge or expectation or within
ten (10) days of the Lessor making such determination and giving written notice
of the same to the Construction Agent, as referenced in subsections (i) and (ii)
above of this paragraph) with one of the options set forth in the following
subsections (A) or (B) (collectively, the "Construction Agent Options"): (A) the
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Construction Agent shall pay to the Lessor, on a date designated by the Lessor,
an aggregate amount equal to (x) the Termination Value, plus (y) any and all
fees and expenses incurred by or on behalf of the Lessor in connection with the
Property (including without limitation the transfer thereof) and on such date
the Lessor shall transfer and convey to the Construction Agent all right, title
and interest of the Lessor in and to the Property, or (B) the

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Construction Agent shall pay to the Lessor, on a date designated by the Lessor,
any and all amounts that are due hereunder or under any other Operative
Agreement upon the occurrence of an Agency Agreement Event of Default, subject
to the limitation provided for in Section 5.4(a), and on and after such date,
the Construction Agent and the Lessee shall be irrevocably deemed, without any
further action, to have relinquished, and shall relinquish in accordance with
Section 10.2 of the Lease, all of its right, title and interest in and to all,
but not less than all, the Property and to have transferred and conveyed all
such right, title and interest to the Lessor, and the Construction Agent shall
execute and deliver to the Lessor or its designee, at the cost and expense of
the Construction Agent, each of the following: (w) special or limited warranty
Deeds and other appropriate assignments conveying the Property to the Lessor or
its designees free and clear of the Lien of the Lease, and the Lien of the
Credit Documents; (x) a Bill of Sale conveying the Property (to the extent they
consist of personal property) to the Lessor or its designee free and clear of
the Lien of the Lease, and the Lien of the Credit Documents; and (y) any real
estate tax affidavit or other document required by law to be executed and filed
in order to record the applicable deed or other assignments. In connection with
any transfer of the Improvements as referenced above in this Section 2.6(c) by
the Lessor to the Construction Agent, the Lessor shall execute and deliver to
the Construction Agent, at the cost and expense of the Construction Agent
(subject to the limitations described in the next sentence), each of the
following: (w) special or limited warranty deeds and other appropriate
assignments conveying the Property to the Construction Agent free and clear of
the Lien of the Lease, the Lien of the Credit Documents and any Lessor Liens;
(x) a bill of sale conveying the Property (to the extent they consist of
personal property) to the Construction Agent free and clear of the Lien of the
Lease, the Lien of the Credit Documents and any Lessor Liens; and (y) any real
estate tax affidavit or other document required by law to be executed and filed
in order to record the applicable deed or other assignments. The Lessor shall
elect whether the out-of-pocket fees and expenses associated with the transfer
of the Property shall be paid by either (i) sales proceeds from the Property,
(ii) the Lessor (but only to the extent amounts are available therefor with
respect to the available SPC Loan Commitment and the available Investor
Contribution Commitment or SPC and each Investor approves the necessary
increases in the available SPC Loan Commitment and the available Investor
Contribution Commitment to fund such fees and expenses), or (iii) the
Construction Agent; provided, if the Construction Agent funds such fees and
expenses (as referenced in subsection (iii)) then the amounts payable under
clause (B) of the Construction Agent Options will be reduced accordingly.
Amounts funded by SPC and the Investors with respect to the foregoing shall be
added to the Project Costs. All of the foregoing documentation must be in form
and substance reasonably satisfactory to the Lessor. Subject to the foregoing,
the Property shall be conveyed to the Construction Agent "AS-IS", "WHERE-IS" and
in its then present physical condition.

     (d) In the event the costs in excess of any original Budget previously
delivered to the Administrative Agent for the Improvements are not funded by SPC
and the Investors because (after taking into account such excess costs and any
other items of excess cost which are then known to the Construction Agent or are
reasonable for the Construction Agent to expect) the conditions precedent set
forth in Section 6.3 of the Participation Agreement are not satisfied, then if,
but only if, the Banks and all the Investors agree at such time, (a) such excess
costs shall be funded and (b) the SPC Loan Commitment and the Investor
Contribution Commitment shall be increased accordingly.

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                          SECTION 3. THE IMPROVEMENTS

     3.1 Amendments; Modifications. (a) The Construction Agent may at any time
         -------------------------
revise, amend or modify (i) the Plans and Specifications without the consent of
the Lessor; provided that any such revision, amendment or modification to the
Plans and Specifications does not (x) result in the Completion Date occurring
after the Outside Completion Date and/or (y) result in the Project Costs subject
to such amendment exceeding the sum of the then SPC Loan Commitments and the
then Investor Contribution Commitments, and (ii) the Budget; provided that such
revisions, amendments or modifications to the Budget do not result in any
increase in the Project Costs greater than the sum of the then SPC Loan
Commitments and the then Investor Contribution Commitments.

     (b) The Construction Agent agrees that it will not implement any revision,
amendment or modification to the Plans and Specifications if the aggregate
effect of such revision, amendment or modification would be to reduce the Fair
Market Sales Value of the Property as set forth in the Appraisal of the
Property, below the sum of the then outstanding SPC Loan and Investor
Contribution when completed, unless such revision, amendment or modification is
required by Legal Requirements or Insurance Requirements.

                          SECTION 4. PAYMENT OF FUNDS

     4.1 Right to Receive Construction Cost. (a) During the course of the
         ----------------------------------
construction of the Improvements, the Construction Agent may request that the
Lessor advance funds for the payment of Project Costs, and the Lessor will
comply with such request to the extent provided for under the Participation
Agreement. The Construction Agent and the Lessor acknowledge and agree that the
Lessee's right to request funds and the Lessor's obligation to advance funds for
the payment of Project Costs is subject in all respects to the terms and
conditions of the Participation Agreement and each of the other Operative
Agreements.

     (b) The proceeds of any funds made available to the Lessor to pay Project
Costs shall be made available to the Construction Agent or its designee in
accordance with the Requisition relating thereto and the terms of the
Participation Agreement. The Construction Agent will use such proceeds only to
pay the Project Costs set forth in the Requisition relating to such funds.

     (c) Notwithstanding anything herein to the contrary, the Lessor shall not
be required to make advances to pay or reimburse or compensate the Construction
Agent with respect to or arising out of a Construction Period Force Majeure
Event, including a Construction Period Force Majeure Event Loss.

                          SECTION 5. EVENTS OF DEFAULT

     5.1 Events of Default. If any one or more of the following events (each, as
     ---------------------
used in this Agreement, an "Agency Agreement Event of Default") shall occur:
                            ---------------------------------

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     (a) the Construction Agent fails to apply any funds paid by the Lessor to
the Construction Agent for the construction of the Improvements to the payment
of Project Costs; or

     (b) the Construction Commencement Date with respect to the Improvements
does not occur within three (3) months of the Closing Date; provided, that the
                                                            --------
failure to commence construction within such three (3) month period shall not be
deemed a breach hereunder if such delay is caused by a Force Majeure Event and
the Construction Commencement Date occurs within three (3) months of the date
otherwise applicable but for this proviso; provided, further, to the extent such
                                           --------  -------
failure to commence construction of the Improvements is caused by a Force
Majeure Event extending beyond such three (3) month period, the Construction
Agent shall elect one of the Construction Agent Options set forth in Section 2.6
and, if such election is not made within ten (10) Business Days of the end of
such three (3) month period, the Construction Agent shall be deemed to have
elected to purchase all the Properties for the Termination Value in accordance
with the provisions of Section 2.6; or

     (c) the Construction Agent shall fail to observe its covenants set forth in
Section 6 hereof; or;

     (d) the Construction Agent shall fail to observe its covenants set forth in
Section 2.5(b) hereof and such failure shall have continued for thirty (30) days
after the date on which written notice thereof has been given to the
Construction Agent by the Lessor; provided, however, that so long as the
Construction Agent is making diligent efforts to cure such breach, the
Construction Agent shall not be in default during such longer period as is
reasonable for a curable breach which the Construction Agent is continuing in
its diligent efforts to cure, provided that in no event shall such breach
continue for a period in excess of an additional ninety (90) days; or

     (e) the Construction Agent shall fail to observe or perform any covenant
(other than any covenant described in clause (a), (b), (c) or (d) above) made by
it herein and such failure shall have continued for thirty (30) days after the
date on which written notice thereof has been given to the Construction Agent by
the Lessor; provided, however, that so long as the Construction Agent is making
diligent efforts to cure such breach, the Construction Agent shall not be in
default during such longer period as is reasonable for a curable breach which
the Construction Agent is continuing in its diligent efforts to cure, provided
that in no event shall such breach continue for a period in excess of an
additional ninety (90) days; or

     (f) the Construction Agent shall (i) admit in writing its inability to pay
its debts generally as they become due, (ii) file a petition under the United
States bankruptcy laws or any other applicable insolvency law or statute of the
United States of America or any State or Commonwealth thereof, (iii) make a
general assignment for the benefit of its creditors, (iv) consent to the
appointment of a receiver of itself or the whole or any substantial part of its
property, (v) fail to cause the discharge of any custodian, trustee or receiver
appointed for it or the whole or a substantial part of its property within sixty
(60) days after such appointment, or (vi) file a petition or answer seeking or
consenting to reorganization under the United States bankruptcy laws or any
other applicable insolvency law or statute of the United States of America or
any State or Commonwealth thereof; or

     (g) insolvency proceedings or a petition under the United States bankruptcy
laws or any other applicable insolvency law or statute of the United States of
America or any

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<PAGE>

State or Commonwealth thereof, (iii) make a general assignment for the benefit
State or Commonwealth thereof shall be filed against the Construction Agent and
not dismissed within sixty (60) days from the date of its filing (provided, that
the Construction Agent hereby expressly authorizes the Lessor to appear in any
court conducting any such proceeding during such sixty (60) day period to
preserve, protect and defend their respective rights under the Operative
Agreements), or a court of competent jurisdiction shall enter an order or decree
appointing, without the consent of the Construction Agent, a receiver of the
Construction Agent or the whole or a substantial part of any of their respective
property, and such order or decree shall not be vacated or set aside within
sixty (60) days from the date of the entry thereof; or

     (h) any representation or warranty made or deemed made by the Construction
Agent herein or in the Participation Agreement or which is contained in any
certificate or Requisition furnished at any time in connection with the
construction of the Improvements shall prove to have been incorrect, false or
misleading in any material respect on or as of the date made or deemed made;

     then, in any such event, and subject to Section 5.3(b), the Lessor may, in
addition to the other rights and remedies provided for in this Article,
terminate this Agreement by giving the Construction Agent five (5) days notice
of such termination and upon the expiration of the time fixed in such notice,
this Agreement shall terminate and all rights and obligations of the
Construction Agent and the Lessor under this Agreement shall cease. Subject to
the limitations of Section 5.4, the Construction Agent shall pay all costs and
expenses incurred by or on behalf of the Lessor, including reasonable fees and
expenses of counsel, and, upon demand, Termination Value, as a result of any
Agency Agreement Event of Default.

     5.2 Damages. The termination of this Agreement pursuant to Section 5.1
     -----------
shall in no event relieve the Construction Agent of its liability and
obligations hereunder, all of which shall survive any such termination.

     5.3 Remedies; Remedies Cumulative.
     ---------------------------------

     (a) Termination of Commitments, Acceleration, etc. Upon the occurrence and
         ---------------------------------------------
continuance of any Agency Agreement Event of Default of the type described in
Section 5.1(f) or Section 5.1(g), the Investor Contribution Commitments and the
SPC Loan Commitments shall automatically terminate and the Construction Agent
shall immediately become obligated to pay the then outstanding amount of the
Termination Value, without presentment, demand, protest, notice of acceleration
or other notice of any kind, all of which are hereby expressly waived, anything
in this Agreement or any other Operative Document to the contrary
notwithstanding. After the occurrence and continuance of any other Agency
Agreement Event of Default, the Lessor may by written notice to the Construction
Agent, immediately (x) terminate all Commitments, (y) terminate this Agreement
(and upon the giving of such notice, this Agreement shall terminate and all
rights of the Construction Agent and all obligations of the Lessor under this
Agreement (as the case may be) shall cease) and/or (z) subject to the
limitations imposed under Section 5.4, accelerate the amounts due and owing by
the Construction Agent hereunder and, upon any such notice of acceleration, the
Construction Agent shall, subject to the limitations imposed under Section 5.4,
immediately become obligated to pay all such amounts.

     (b) If (x) a Fully Indemnifiable Event shall have occurred, (y) an Event of
Default shall have occurred and be continuing and the occurrence of which is
Within the Construction Agent's Control (whether or not constituting, or arising
out of, a Fully

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Indemnifiable Event), or (z) any Agency Agreement Event of Default described in
Section 5.1(b) or 5.1(d) shall have occurred and be continuing and the
occurrence of which is Within the Construction Agent's Control (whether or not
constituting, or arising out of, a Fully Indemnifiable Event) and the
Construction Agent and/or the Lessee shall have failed to relinquish all of its
interest in the Property, convey possession thereof to the Lessor or its
designee in compliance with Section 5.4(a) and/or shall have failed to comply
with the indemnification obligations under Section 12 of the Participation
Agreement, then, in each such case set forth in clauses (x), (y) and (z) above,
the Lessor shall have all rights and remedies available under the Operative
Agreements (including under Section 17.3 of the Lease) or available at law,
equity or otherwise, including the right to declare the Termination Value due
and owing.

     (c) No failure to exercise and no delay in exercising, on the part of the
Lessor, any right, remedy, power or privilege under this Agreement or under any
other Operative Agreement shall operate as a waiver thereof nor shall any single
or partial exercise of any right, remedy, power or privilege under this
Agreement preclude any other or further exercise thereof or the exercise of any
other right, remedy, power or privilege. The rights, remedies, powers and
privileges provided in this Agreement are cumulative and not exclusive of any
rights, remedies, powers and privileges provided by law.

     5.4 Limitation on Construction Agent's Recourse Liability. (a)
     ---------------------------------------------------------
Notwithstanding anything contained herein or in any other Operative Agreement to
the contrary, if (i) an Agency Agreement Event of Default described in Section
5.1(b) or 5.1(d) the occurrence of which is not Within the Construction Agent's
Control and does not constitute, and is not the result of, a Fully Indemnifiable
Event (a "Construction Risk Event") and (ii) no other Event of Default has
          -----------------------
occurred and is continuing (x) the occurrence of which is Within the
Construction Agent's Control, or (y)which does not constitute, and is not the
result of, a Fully Indemnifiable Event, then so long as the Construction Agent
relinquishes all of its interest in the Property and conveys possession thereof
to the Lessor or its designee in compliance with all Environmental Laws and the
requirements of Section 10.1 and 10.2 of the Lease (other than any such
requirement which requires completion of the Improvements), accompanied by an
affidavit to the Lessor to such effect and appropriate statements of
termination, the aggregate maximum recourse liability of the Construction Agent
with respect to such default to the Lessor or any Person claiming by, through or
under the Lessor under the Operative Agreements, shall be limited to the
Non-Completion Amount. The Construction Agent nonetheless acknowledges and
agrees that, subject to the provisions of Section 13.8(b) of the Participation
Agreement, (i) the Lessor shall be entitled to recover from the Property
(including through any reletting and/or sale of the Property or any portion
thereof) the entire outstanding funded amount of the SPC Loans and Investor
Contributions at the time of such Agency Agreement Event of Default, along with
all accrued and unpaid interest on the outstanding amount of the SPC Loans,
yield on the outstanding Investor Contributions and other amounts then due and
owing to the Lessor under the Operative Agreements and all other costs and
expenses of the Lessor incurred in connection with the Property (including
without limitation, any costs incurred in connection with the construction of
the Improvements and/or any reletting or sale of such Property or any portion
thereof) from and after the date of such return, and (ii) the foregoing recourse
limitations are exclusive of any amounts due and owing under Section 12 of the
Participation Agreement.

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     (b) The proceeds received from any sale of the Property after the
Construction Agent has relinquished its interest in the Property pursuant to
Section 5.4(a) above shall be applied in accordance with Section 13.8 of the
Participation Agreement.

     5.5 Construction Agent's Right to Purchase. In the event that an Agency
     ------------------------------------------
Agreement Event of Default (other than an Agency Agreement Event of Default
under Section 5.1(f) or Section 5.1(g)), shall have occurred and be continuing,
the Construction Agent shall have the irrevocable option to purchase the
Property for a price equal to the Termination Value as of the date of such
purchase plus all other amounts due and owing hereunder, under the Participation
Agreement and the other Operative Agreements, such purchase to be effected in
accordance with the procedures set forth in Section 20 of the Lease; provided
that the Construction Agent shall have given written notice whether or not it
intends to do so within five (5) Business Days after the occurrence of such
Agency Agreement Event of Default and provided, further, that the Construction
Agent shall purchase the Property and pay all amounts due in connection
therewith within twenty (20) days after the occurrence of such Agency Agreement
Event of Default. If Lessor does not receive such a purchase notice within such
five (5) day period, then the Construction Agent shall be deemed to have
irrevocably elected to purchase the Property. The Construction Agent's purchase
of the Property in accordance with this Section 5.5 shall be deemed to cure the
applicable Agency Agreement Event of Default.

                     SECTION 6. INSURANCE AND CONDEMNATION

     6.1 Insurance. The Construction Agent shall procure and maintain in full
     -------------
force and effect or arrange to be procured and maintained in full force and
effect insurance for the Improvements during the Construction Period in
accordance with the following provisions:

     (a) Public Liability and Workers' Compensation Insurance. During the
         ----------------------------------------------------
Construction Period, the Construction Agent shall procure and carry or cause to
be procured and carried, at the Construction Agent's sole cost and expense,
commercial general liability insurance for the Construction Period risks arising
from the acts, errors or omissions of the Construction Agent while located on,
in possession of, or controlling or acting or failing to act with respect to the
Land and Construction. In addition, during the Construction Period, the
Construction Agent shall, in the construction of the Improvements on the Land
and the operation of the Land, comply with all applicable workers' compensation
laws. The Construction Agent acknowledges and agrees in this connection that the
Property is in its control and possession during the Construction Period
therefor, it is responsible as Construction Agent for the acts, errors or
omissions of its contractors, subcontractors and agents and that it has assumed
all liability arising from injury, damage or mishap to third Persons caused by
the Construction Agent or any person or entity under its control.

     (b) Hazard and Other Insurance. During the Construction Period, the
         --------------------------
Construction Agent shall arrange, on behalf of the Lessor, to obtain from an
insurance provider reasonably acceptable to the Lessor, and utilizing funds
advanced by the Lessor and keep in force a policy or policies of Builder's Risk
"All Risk" insurance with respect to the Land and Improvements insuring the
Lessor's interest in the Land and Improvements including collapse coverage and
fire insurance with extended coverage, written on a Standard Builder's Risk
Completed Value Form (100% non-reporting), in an amount equal to 100% of the
completed insurable replacement cost value of the Property. In addition, the
Construction Agent shall

                                      -11-
<PAGE>

arrange, on behalf of the Lessor and utilizing funds provided by the Lessor, for
the Lessor to obtain insurance from damage caused by collapse, flood or
earthquake covering losses up to $750 million. All such policies shall be in
form and substance reasonably satisfactory to the Lessor. The Lessor shall be
the named the mortgagee and loss payee under such policies. The premiums for
such coverage shall be paid with the proceeds of an advance of funds made by
Lessor for the Project Costs. In addition, the reduction in any recovery
pursuant to any deductible applicable to such policy shall be deemed a Project
Cost paid with the proceeds of an advance made by Lessor therefor; and,
provided, however that, unless the Lessor otherwise agrees, the deductible under
the all risk insurance policy required pursuant to this clause (b) shall not
exceed $100,000 per incident, loss or occurrence.

     (c) Deductibles. The insurance required to be obtained by the Construction
         -----------
Agent under Section 6.1(a) may be subject to such deductible amounts as is
consistent with the Construction Agent's or its Affiliates practice for other
properties similar to the Property owned or leased by the Construction Agent or
the Affiliates of the Construction Agent, and may be carried under blanket
policies maintained by or on behalf of the Construction Agent so long as such
policies otherwise comply with the provisions of this Section 6.1. The all risk
insurance required to be obtained by the Lessee pursuant to Section 6.1(b) shall
contain no deductible amount in excess of $100,000 per incident, loss or
occurrence unless the Lessor otherwise agrees.

     (d) Construction Manager. Should the Construction Agent decide to utilize
         --------------------
the services of a "Construction Manager or General Contractor", hereinafter
called the Construction Manager, on the Project, then said Construction Manager
shall procure and maintain, at its own expense, the following required insurance
of the kinds and limits as stipulated hereunder:

     (1) Worker's Compensation and Employer's Liability Insurance in accordance
with the applicable laws of the State in which the work is to be performed or of
the State in which the Construction Manager is obligated to pay compensation to
employees engaged in the performance of the work associated with this Project.
The policy limit under the Employer's Liability Insurance section shall not be
less than $1,000,000 (One Million Dollars) for any one accident. (2) Commercial
General Liability Insurance covering the work, the performance of the work and
everything incidental thereto, with limits of not less than $100,000,000 (One
Hundred Million Dollars) per occurrence combined single limit, or in whatever
higher amounts as may be required, and extended to cover: (a) Contractual
Liability Insurance assumed by the Construction Manager under any
Indemnification Agreement related to this Project, (b) if any of the work is
subcontracted, Independent Contractors Liability Insurance providing coverage in
connection with such portion of the work which may be subcontracted, (c) Broad
Form Property Damage Liability Insurance, and (d) Personal Injury Liability
Insurance. (3) Automobile Liability Insurance including coverage on owned, hired
and non-owned automobiles and other vehicles, if used in connection with the
performance of the work, with Bodily Injury and Property Damage limits of not
less the $50,000,000 (Fifty Million Dollars) per occurrence combined single
limit.

                                      -12-
<PAGE>

     (e)  Coverage. All insurance required to be carried or arranged for by the
          --------
Construction Agent or Construction Manager, accordingly, pursuant to the
requirements of Section 6.1(a), 6.1(b) or 6.1(d) shall provide in the policy or
by special endorsement that:

          (i)   in the case of insurance required by Section 6.1(a), that the
     Participants (except for the Banks) are included as additional insureds;

          (ii)  the insurer thereunder waives all rights of subrogation against
     the Lessor, and waives any right of set-off and counterclaim and any other
     right to deduction whether by attachment or otherwise;

          (iii) in case of insurance required by Section 6.1(d) such insurance
     shall be primary and shall apply to any loss or claim before any
     contribution of any other insurance carried by or on behalf of the Lessor
     or the Construction Agent;

          (iv)  the respective interests of the Lessor or the Construction
     Agent, as the case may be, under all insurance policies required hereunder
     shall not be invalidated by any action or inaction of the Lessee or the
     Construction Agent or any other Person (other than, with respect to any
     such insured, such insured) and such insurance shall insure the Lessor's
     interests, regardless of any breach or violation of any warranty,
     declaration or condition contained in such policies by the Lessee, the
     Construction Agent or any other Person (other than, with respect to any
     such insured, such insured);

          (v)   if the insurers cancel such insurance for any reason whatsoever
     or any materially adverse change is made in policy terms or conditions, or
     if such insurance is allowed to lapse for nonpayment of premium, such
     cancellation, change or lapse shall not be effective as to the Lessor for
     thirty (30) days after receipt by the Lessor of written notice from such
     insurers of such cancellation, change or lapse; and

          (vi)  with respect to all liability insurance, in as much as the
     policies are written to cover more than one insured, all terms, conditions,
     insuring agreements and endorsements, with the exception of the limits of
     liability, shall operate in the same manner as if there were a separate
     policy covering each insured.

     (f)  Adjustment of Losses. Losses, if any, with respect to the Property
under any damage policies required to be carried under Section 6.1(b) shall be
adjusted with the insurance companies, including the filing of appropriate
proceedings, as follows: (x) so long as no Agency Agreement Default shall have
occurred and be continuing, and provided that the Construction Agent is
required, or has agreed, to repair the damage, such losses shall be adjusted by
the Construction Agent, and (y) if any Agency Agreement Default shall have
occurred and be continuing, or if the Construction Agent is not required to, and
has not agreed, to repair the damage, such losses shall be adjusted by the
Lessor. The party which shall be entitled to adjust losses may appear in any
proceeding or action to negotiate, prosecute, adjust or appeal any claim for any
award, compensation or insurance payment on account of any Casualty and shall
pay all expenses thereof. At such party's reasonable request, and at the
Construction Agent's sole cost and expense with respect to disputes on insurance
required under Section 6.1(a), the

                                      -13-
<PAGE>

Construction Agent, and the Lessor, as the case may be, shall participate in any
such proceeding, action, negotiation, prosecution or adjustment. The parties
hereto agree that this Agreement shall control the rights of the parties hereto
in and to any such award, compensation or insurance payment relating to any
Casualty affecting the Property during the Construction Period.

     (g)  Application of Insurance Proceeds. All proceeds of insurance
          ---------------------------------
maintained pursuant to Section 6.1(b) on account of any damage to or destruction
of the Property during the Construction Period or any part thereof shall be paid
over to the Lessor or as it may direct; provided that if no Agency Agreement
Default shall have occurred such funds shall be held by the Lessor in a
segregated account and, so long as the Construction Agent is diligently
repairing the damage to the Property caused by the applicable Casualty,
disbursed to the Construction Agent to effect the repair of the Property.

     (h)  Title Insurance. Construction Agent shall cause the Title Company to
          ---------------
issue the title insurance referred to in Section 6.3(d) of the Participation
Agreement.

     (i)  Additional Insurance. Any additional insurance obtained by the
          --------------------
Construction Agent or the Lessor shall provide that it shall not limit the
insurance described in Sections 6.1(a) and 6.1(b) or increase the amount of any
premium payable with respect to any such insurance. The proceeds of any
additional insurance will be for the account of the party maintaining such
additional insurance.

     (j)  Insurance Report. On the commencement of construction of the
          ----------------
Improvements and annually thereafter, the Construction Agent shall provide the
Lessor, promptly following Lessor's written request therefor, an insurance
certificate certifying compliance with the insurance then required to be
maintained by the Construction Agent pursuant to this Section 6.1, provided
however, the Construction Agent shall provide the Lessor with written notice
thirty (30) days prior to the expiration of any insurance policy required to be
maintained pursuant to the terms of this Agreement.

     6.2  Condemnation.
     -----------------

     (a)  Representation and Warranties of the Construction Agent with respect
          --------------------------------------------------------------------
to Condemnation. The Construction Agent hereby represents and warrants to the
---------------
Lessor (which representation and warranty shall be deemed to be repeated and be
considered part of each Requisition) that to the actual knowledge of the
Construction Agent there is no action being taken by any Person with respect to
any actual, pending or threatened Condemnation affecting the Property.

     (b)  Condemnation Occurrences.
          ------------------------

               (i)    Condemnation Proceedings. The Construction Agent hereby
                      ------------------------
     agrees that it shall, within five (5) Business Days after the date on which
     the Construction Agent shall have notice thereof, give notice to the Lessor
     of each action or proceeding by any Governmental Authority with respect to
     any actual, pending or threatened Condemnation during the Construction
     Period and whether or not as a result thereof Completion of the
     Improvements will be completed on or before the Outside Completion Date and
     is exercising a Construction Agent Option pursuant to Section 2.6(c).
     During the Construction Period, the Lessor shall be entitled, to the
     exclusion of the Construction Agent, to negotiate,

                                      -14-
<PAGE>

     prosecute, adjust or appeal any claim for any award, compensation or
     insurance payment on account of any Condemnation having a material effect
     on the Property. The Lessor shall consult with the Construction Agent in
     connection with the foregoing, but the Construction Agent shall have no
     right to participate in any such negotiation, prosecution, adjustment or
     appeal unless the Lessor consents thereto in its sole discretion. During
     the Construction Period, the Construction Agent shall be entitled, with the
     approval of the Lessor, which shall not be unreasonably withheld,
     conditioned or delayed, to negotiate, prosecute, adjust or appeal any claim
     for any award, compensation or insurance payment on account of any
     Condemnation which does not have a material effect on the Property.

               (ii)    Condemnation Awards. During the Construction Period, all
                       -------------------
     awards, compensation and insurance payments on account of any Condemnation
     affecting the Property shall be paid directly to the Lessor or, if received
     by the Construction Agent, shall be held in trust for the Lessor and shall
     promptly be paid over by the Construction Agent to the Lessor. In the event
     the Construction Agent elects to proceed under clause (A) of the definition
     of "Construction Agent Options" in Section 2.6(c), all such amounts paid to
     Lessor shall be paid to the Construction Agent upon Lessor receiving all
     amounts due under such clause (A), and if no Construction Agent Option
     shall have been exercised, and the Property suffering a Condemnation is in
     the reasonable judgment of the Lessor capable of being restored to a
     condition, functionally and economically, equivalent to that which existed
     prior to such Condemnation for a restoration cost equal to or less than the
     award or compensation received by the Lessor with respect to the
     Condemnation, then, so long as no Agency Agreement Default has occurred and
     is continuing and such restoration can be completed on or prior to the
     Outside Completion Date, then such award or compensation shall be made
     available to the Construction Agent to finance such restoration and the
     Construction Agent shall effect such restoration on or prior to the Outside
     Completion Date. To the extent the Lessor elects to retain such award or
     compensation and apply it to the Termination Value and such award or
     compensation exceeds the Termination Value, such amount shall be applied in
     accordance with Section 13.5(b) and 13.5(c) of the Participation Agreement.

            SECTION 7. LESSOR'S RIGHTS; CONSTRUCTION AGENT'S RIGHTS

     7.1 Exercise of the Lessor's Rights. Subject to the terms of the Contract
     -----------------------------------
Assignment made by the Lessor in favor of the Administrative Agent, the
Construction Agent hereby acknowledges and agrees that the rights and powers of
the Lessor under this Agreement have been assigned to the Administrative Agent.

     7.2 Lessor's Right to Cure Construction Agent's Defaults. Upon written
     --------------------------------------------------------
notice to the Construction Agent, except in emergencies, the Lessor, without
waiving or releasing any obligation or Agency Agreement Event of Default, may
(but shall be under no obligation to) remedy any Agency Agreement Event of
Default hereunder for the account of and at the sole cost and expense of the
Construction Agent, subject to the limitations on Construction Agent's liability
to

                                      -15-
<PAGE>

Lessor set forth herein. All reasonable out of pocket costs and expenses so
incurred (including reasonable fees and expenses of counsel), together with
interest thereon at the Overdue Rate from the date on which such sums or
expenses are paid by the Lessor, shall be paid by the Construction Agent to the
Lessor on demand.

          7.3 Subordination. (a) All liabilities and obligations of the Lessor
          -----------------
     to the Construction Agent, whether secured or unsecured and whether or not
     evidenced by any instrument, now existing or subsequently created or
     incurred, are and shall be subordinate and junior in right of payment to
     the Secured Obligations.

          (b) The Construction Agent shall not sell, assign or otherwise
     transfer, in whole or in part, or create, incur or suffer to exist any
     security interest, Lien, charge or other encumbrance with respect to any
     indebtedness, liabilities or obligations of the Lessor to the Construction
     Agent or any instrument or document evidencing or securing the same unless,
     in any such case, the person or entity to whom such sale, assignment or
     transfer is made or the beneficiary of such security interest, Lien, charge
     or encumbrance acknowledges the foregoing subordination and agrees to be
     bound thereby. Notwithstanding the foregoing, the Lessor acknowledges
     Lessee's right to finance and to secure under the Uniform Commercial Code,
     inventory, furnishings, furniture, equipment, machinery, leasehold
     improvements and other personal property located at the Property, other
     than the Equipment, Modifications and other such items which are purchased
     with the proceeds of SPC Loans or Investor Contributions or which are
     otherwise required to be titled in the name of Lessor and excluding in all
     cases fixtures, and Lessor agrees, at Construction Agent's request and at
     Lessee's cost and expenses, to execute waiver forms, releases of Lessor
     Liens and other similar documentation (in form and substance reasonably
     satisfactory to Lessor and the Administrative Agent) in favor of any
     purchase money seller, lessor or lender who has financed or may finance in
     the future such items, with respect to such separately-financed items only.

          (c) Should any payment or distribution or security, or any proceeds
     thereof, be collected or received by the Construction Agent in respect of
     any indebtedness, liabilities or obligations of the Lessor to the
     Construction Agent, and such collection or receipt is not permitted under
     these subordination provisions of this Agreement, the Construction Agent
     shall immediately turn over such payment, distribution or security or
     proceeds to the Administrative Agent, in the form received, and, until so
     turned over, the same shall be held in trust by the Construction Agent as
     the property of the Lenders.

          (d) For purposes of this Agreement "subordinate and junior in right of
     payment" shall mean: no part of any subordinated indebtedness, liabilities
     or obligations shall have any claim to the assets of the Lessor on a parity
     with or prior to the claim of the Obligations or the principal amount of
     the Loans and other amounts due to the Administrative Agent, the Lenders
     and the Investor. Unless and until the Obligations shall have been fully
     paid and satisfied, the Construction Agent will not take, demand or
     receive, directly or indirectly, by set-off, redemption, purchase or in any
     manner, any payment or security for the whole or any part of any
     subordinated indebtedness, liabilities or obligations, and the Construction
     Agent will not accelerate the scheduled maturities of any amounts owing on
     account of such indebtedness, liabilities or obligations or demand payment
     thereof; provided that so long as no Default or Event of Default exists or
     would be in existence immediately after giving effect to such payment, the
     Construction Agent may receive currently scheduled payments on account of
     such indebtedness, liabilities and obligations.

                                      -16-
<PAGE>

          7.4 Right to Inspect. During the Construction Period, the Construction
          --------------------
     Agent shall upon reasonable written notice from the Lessor, permit the
     Lessor, the Administrative Agent acting on behalf of the Banks, and their
     respective authorized representatives to inspect the Property in accordance
     with Section 10.3 of Lease subject to this Construction Agency Agreement
     and the books and records of the Construction Agent relating to the
     Property during normal business hours, provided that such inspections shall
                                            --------
     be without notice in the event of an emergency.

          7.5 Costs and Fees. Except for such obligations, duties and
          ------------------
     requirements which are included as part of the Project Costs, all
     obligations, duties and requirements imposed upon or allocated to the
     Construction Agent shall be performed by the Construction Agent at the
     Construction's Agent's sole cost and expense. The Construction Agent will
     not be entitled to, and the Lessor shall have no obligation to pay, any
     agency fee, and the Construction Agent shall not be entitled to, and the
     Lessor shall have no obligation to make or pay, any reimbursement
     therefore, it being understood that this Agreement is being entered into as
     consideration for and as an inducement to the Lessor and the Construction
     Agent entering into the Lease and the other Operative Agreements.

                            SECTION 8. MISCELLANEOUS

          8.1 Notices. Unless otherwise specifically provided herein, all
          -----------
     notices, consents, directions, approvals, instructions, requests and other
     communications required or permitted by the terms hereof to be given to any
     Person to be effective shall be given in writing and in the manner provided
     in, and the effectiveness thereof shall be governed by the provisions of
     Section 14.3 of the Participation Agreement.

          From time to time any party may designate a new address for purposes
     of notice hereunder by notice to each of the other parties hereto.

          8.2 Successors and Assigns. This Agreement shall be binding upon and
          --------------------------
inure to the benefit of the Lessor, the Construction Agent and their respective
successors and assigns.

          8.3 GOVERNING LAW. THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS OF
          -----------------
THE PARTIES UNDER THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK, EXCEPT TO THE
EXTENT THE LAWS OF THE STATE OF WASHINGTON ARE REQUIRED TO APPLY WITH RESPECT TO
THE PROPERTY AND ANY AGREEMENTS ENTERED INTO BY CONSTRUCTION AGENT IN SUCH STATE
PURSUANT TO THE AUTHORITY GRANTED IN SECTION 2.3 HEREOF.

          8.4 Amendments and Waivers. The Lessor and the Construction Agent may
          --------------------------
from time to time, enter into written amendments, supplements or modifications
hereto.

          8.5 Counterparts. This Agreement may be executed on any number of
          ----------------
separate counterparts and all of said counterparts taken together shall be
deemed to constitute one and the same instrument.

                                      -17-
<PAGE>

          8.6 Severability. Any provision of this Agreement which is prohibited
          ----------------
or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

          8.7 Headings and Table of Contents. The headings and table of contents
          ----------------------------------
contained in this Agreement are for convenience of reference only and shall not
limit or otherwise affect the meaning hereof.

          8.8 Duty to Notify. To the extent that Lessor, as the owner of record
          ------------------
of the Property, receives any written notice, directions, instructions,
requests, demands or other communications from any third party or any
Governmental Authority relating to Construction Agent's rights and obligations
under this Agreement or the Lessee's rights and obligations under the Lease,
Lessor agrees to provide Construction Agent with prompt written notice of such,
including a true copy of all written materials received by Lessor relating
thereto.

          8.9 Liability of Wilmington Trust Company. It is expressly understood
          -----------------------------------------
and agreed by the parties hereto that (i) except as specifically provided for in
this Agreement, this Agreement is executed and delivered by Wilmington Trust
Company not individually or personally but solely as trustee of the Trust, in
the exercise of the powers and authority conferred and vested in it, (ii) each
of the representations, undertakings and agreements herein made on the part of
Lessor or Wilmington Trust Company, as the case may be, is made and intended not
as personal representations, undertakings and agreements by Wilmington Trust
Company but is made and intended for the purpose of binding only the Lessor,
(iii) except as specifically provided for in this Agreement nothing herein
contained shall be construed as creating any liability on Wilmington Trust
Company, individually or personally, to perform any covenant either expressed or
implied contained herein, all such liability, if any, being expressly waived by
the parties hereto and by any Person claiming by, through or under the parties
hereto and (iv) under no circumstances shall Wilmington Trust Company be
personally liable for the payment of any indebtedness or expenses of any party
hereto, or be liable for the breach or failure of any obligation,
representation, warranty or covenant made or undertaken by Lessor under this
Agreement; provided, however, the foregoing shall not limit Wilmington Trust
Company's liability for its own gross negligence or willful misconduct.

                                      -18-
<PAGE>

          IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed and delivered by their proper and duly authorized officers as
of the day and year first above written.

                                  IMMUNEX CORPORATION


                                  By:        /s/ David A. Mann
                                      ------------------------------------
                                      Name: David A. Mann
                                      Title: Executive Vice President, Chief
                                               Financial Officer and Treasurer


                                  IMMUNEX REAL ESTATE TRUST 2001


                                  By: Wilmington Trust Company, not in
                                      its individual capacity but solely
                                      as Trustee

                                      By:        /s/ Patricia Evans
                                          ---------------------------------
                                          Name: Patricia Evans
                                          Title: Senior Financial Services
                                                   Officer

                                      -19-