Exhibit 10.88  FIRST AMENDMENT OF LEASE  THIS FIRST AMENDMENT OF LEASE (First Amendment)
made as of this 28th day of February, 2000 by and between: McCARTHY
ASSOCIATES LIMITED (Landlord)a New Jersey limited partnership
c/o John F. McCarthy, III
228 Alexander Street
P.O. Box 2329
Princeton, NJ  08543-2329 AND MEDAREX,
INC. (Tenant)a New Jersey corporation
1545 Route 22 East
P.O. Box 953
Annandale, NJ  08801-0953 WITNESS: WHEREAS, pursuant to a certain Agreement of Lease
dated July 7, 1999 (Lease), Landlord leased to Tenant certain rentable
office space in the building commonly known as Princeton Gateway Corporate
Campus, located at 707 State Road in Princeton, NJ (Building), and WHEREAS, pursuant to Article 41 of the Lease,
Tenant is obligated to lease the Contiguous Space consisting of 4600 square
feet of rentable space as shown on Exhibit B to the Lease if the
Contiguous Space becomes available for lease during the Term and the Contiguous
Space will be available for lease for a term commencing on or about May 1,
2000, NOW, THEREFORE, in consideration of the mutual
covenants contained herein and other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, Landlord and Tenant
agree as follows: 1.             Definitions.           Unless
otherwise defined in this instrument, all capitalized terms used herein shall
have the meanings ascribed to such terms in the Lease. 2.             Availability Notice.              Landlord hereby gives Tenant an Availability Notice
that the Contiguous Space is available for lease for a term commencing on or
about May 1, 2000. 3.             Leasing, Term
and Increases in Rent and Security.  Landlord hereby leases to Tenant, and Tenant
hereby leases from Landlord, the Contiguous Space pursuant to the terms of the
Lease and this First Amendment for a term commencing on the Contiguous Space
Effective Date (as defined below) and terminating on the Termination Date, for
a fixed rental payable by Tenant to Landlord of $108,100 per  1


year.  On or before the Contiguous Space Effective
Date, Tenant shall deposit with Landlord an additional security deposit of
$18,016.67, increasing the amount of the security deposit to be held in
accordance with Article 36 of the Lease to $43,122.50. 4.             Modifications to Definitions.             As a consequence of the leasingof the
Contiguous Space by Tenant, the following definitions appearing in thepreamble to the Lease are modified to read as
follows from and after the Contiguous Space Effective Date: (a)           Lease or this Lease consists of
the Lease, Exhibits A-1 through G attached thereto and made a part
thereof, this First Amendment and Exhibit H attached hereto and
made a part hereof. (b)           Minimum Rent shall mean the fixed
rental owed by Tenant to Landlord in the amount of $258,735.00 per year,
payable in installments of $21,561.25 per month. (c)           Premises shall mean the portion of
the Building shown as the area marked on the floor plan of the Building as the
Medarex 6410 sq. ft. and the Technology Management 4600 SF, a copy of which
floor plan is annexed to the Lease as Exhibit B and made a part
thereof. (d)           Rentable Area of the Premises shall
mean 11,010 square feet for the purposes of the Lease. (e)           Tenants Proportionate Share shall
mean 29.00%. 5.Other Lease Modifications.                As a further
consequence of the leasing of the Contiguous Space by Tenant, the following
provisions of the Lease are modified to read as follows from and after the
Contiguous Space Effective Date: (a)           The Basic Lease Information cover
sheet is modified to read in full as the same appears as Exhibit H
attached hereto and made a part hereof. (b)           The first sentence of Section 1.2
of the Lease is modified to read in full as follows:  The leasing of the Premises to and by Tenant
includes the non-exclusive right to the use of forty-four (44) automobile
parking spaces. 6.Contiguous Space
Effective Date.    Tenant acknowledges that the Contiguous Space is presently
occupied by Technology Management and Funding (TMF)and thatTMFslease term
expires on April 30, 2000.  In the
event Landlord is unable to deliver possession of the Contiguous Space on May 1,
2000 as a result ofTMFholding over or because Landlord has failed to perform the Landlords
Work described in paragraph 7 below, such failure shall not affect the
validity of this First Amendment. 
Landlord shall not be liable for any damages which Tenant may incur as a
result of the delay in obtaining possession of the Contiguous Space or the completion
of the Landlords Work.  In such event,
Landlord shall take reasonable action to acquire possession of the Contiguous
Space or complete the Landlords Work as soon as reasonably possible.  For the purposes of this First Amendment, the
term Contiguous Space Effective Date shall mean the date on which Landlord
delivers  2


possession of the
Contiguous Space to Tenant, free of all tenancies and occupancies, in broom
clean condition, and with Landlords Work completed. 7.             As Is Condition.   Tenant
acknowledges that except for the Landlords Work described below, Landlord is
not obligated to do any work to the Contiguous Space to prepare it for Tenants
occupancy.  Tenant shall accept the
Contiguous Space in its as is condition as of the Contiguous Space Effective
Date, including, without limitation, the swipe system that provides security
to the Contiguous Space; provided, however, that Tenant assumes no
responsibility in respect to latent defects in the Contiguous Space, the
responsibility for the correction of which resides in Landlord, and provided,
further, that Tenant shall not be required to accept the swipe system unless
Landlord delivers to Tenant clear title to and possession of the computer
hardware and software currently employed byTMFto operate the swipe system. 
Notwithstanding the foregoing, consistent with the provisions of the
Lease, Landlord shall at Landlords cost and expense do all of the following
work (the Landlords Work) prior to the Contiguous Space Effective Date: (a)remove the demising wall separating the Medarex 6410 sq. ft. and the
Technology Management 4600 SF and repair any damage caused by such removal, (b)if Landlord is unable to deliver to Tenant clear title to and possession
of the computer hardware and software currently employed byTMFto operate the swipe system, remove the swipe
system and all of its components from the Contiguous Space and repair any
damage caused by such removal, and (c)paint the Contiguous Space. In addition, if Tenant
notifies Landlord within five (5) business days after the Contiguous Space
Effective Date that the Contiguous Space has been surrendered byTMFin a damaged or other condition that is
inconsistent withTMFs
obligations with respect to the surrender thereof (i.e., that the Contiguous
Space shall be surrendered broom clean, in as good condition as on the
commencement date ofTMFs
lease,ordinary wear and tear, repairs and replacement by Landlord, and
alterations,additions and improvements
permitted thereunder excepted), Landlord shall, at Landlords cost and expense,
immediately commence to make such repairs, alterations, etc. as may be
necessary to restore the condition of the Contiguous Space to the condition inwhich
it was required to be surrendered by TMF,
and prosecute the completion ofsuch repairs
with due diligence. 8.Modification.   ThisFirst Amendment may not be changedorally and shall be binding
upon and inure to the benefit of the parties hereto andtheir respective successors, permitted assigns and legal representatives. 9.             Effectiveness.This First Amendment shall be effective only ifboth Tenant and Landlord shall have signed and delivered to the other
party a copy of this First Amendment and Landlord shall have causedTMFto provide Tenant and Tenants agents with the
right, exercisable at reasonable times and upon reasonable advance notice to
TMF, to enter the Contiguous Space from time to time for the purpose of
examining its condition, taking measurements and interior decorating.  3


10.           Commission.         Tenant represents and warrants to
Landlord that Tenant has not dealt with any real estate broker or sales
representative in connection with this transaction other than Broker.  Tenant shall indemnify and hold harmless
Landlord from and against all threatened or asserted claims, liabilities, costs
ordamages (including reasonable attorneys fees and disbursements) which
Landlordmay incur as a result of a breach of
this representation.  Landlord shall pay
to Broker a commission pursuant to a separate written agreement. 11.           Amended Lease.Except to the extent
expressly modifiedherein, all of the terms
and provisions of the Lease are hereby expressly ratified and confirmed. IN WITNESS WHEREOF the parties have signed this
First Amendment as of the date first written above.  LANDLORD:McCARTHY ASSOCIATES LIMITED
  By: Princeton Gateway Corporation, Inc.
  
  TENANT:MEDAREX, INC./s/ John F. McCarthy, III
  
  /s/ Lisa N. DrakemanJohn F. McCarthy, III, President
  Name:
  Lisa N. DrakemanTitle:
  Senior Vice
  PresidentDated:
  February 29, 2000
  Dated:
  February 28, 2000  4


EXHIBIT H BASIC LEASE INFORMATION  Landlord:
  McCarthy Associates Limited
  a New Jersey limited partnership
  c/o John F. McCarthy, III, Esq.
  228 Alexander Street
  P. O. Box 2329
  Princeton, NJ  08543-2329Tenant:
  Medarex, Inc.
  1545 Route 22 East
  P. O. Box 953
  Annandale, NJ  08801-0953Type of Entity:
  A corporation of the State of New JerseyDefinition
  Base Year: 
  calendar year 1999 for the initial TermDefinition
  Commencement Date: 
  on or about July 2, 1999Definition
  Rentable Area of Building:
  37,966 rentable square feetDefinition
  Rentable Area of Premises:
  11,010 rentable square feetDefinition
  Tenants Proportionate Share:
  29.00%Definition
  Termination Date: 
  (1) Fifth anniversary of the Commencement Date; or (2) Tenth
  Anniversary of the Commencement Date if Tenant exercises its first option to
  renew; or (3) Fifteenth Anniversary of the Commencement Date if Tenant
  exercises its second option to renew.Section 1.3
  Number of Parking Spaces:
  forty-four (44)Section 1.3
  Minimum Rent Per Year:
  $258,735.00Section 1.3
  Minimum Rent Per Month:
  $21,561.25Article 36
  Security Deposit:
  $43,122.50INITIALS:Landlord
  
  Tenant  5


SECOND AMENDMENT OF LEASE THIS SECOND AMENDMENT OF LEASE (Second Amendment) made as of this 26th
day of May, 2000 by and between: McCARTHY ASSOCIATES
LIMITED (Landlord)a New Jersey limited partnership
c/o John F. McCarthy, III
228 Alexander Street
P.O. Box 2329
Princeton, NJ  08543-2329 AND MEDAREX, INC. (Tenant)a New Jersey corporation
707 State Road
Princeton, NJ  08540 WITNESS: WHEREAS, pursuant to a certain Agreement of Lease dated July 7,
1999 (Lease), and First Amendment of Lease dated February 28, 2000 (First
Amendment), Landlord leased to Tenant certain rentable office space in the
building commonly known as Princeton Gateway Corporate Campus, located at 707
State Road in Princeton, New Jersey (Building), and WHEREAS, Tenant is interested in Scauticons existing space consisting
of 3,302 square feet of rentable space as shown on Exhibit I hereto
referred to as Scanticon Expansion Space, NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and adequacy of
which are hereby acknowledged, Landlord and Tenant agree as follows: 1.             Definitions. 
Unless
otherwise defined in this instrument, all capitalized terms used herein shall
have the meanings ascribed to such terms in the Lease. 2.             Leasing, Term and Increases in Rent and Security.  Landlord hereby leases to Tenant, and Tenant hereby
leases from Landlord, the Scanticon Expansion Space pursuant to the terms of
the Lease and this Second Amendment for a term commencing on the Scanticon
Expansion Space Effective Date (as defined below) and terminating on the
Termination Date, for a fixed rental payable by Tenant to Landlord of
$87,503.00 per year.  On or before
signing of this Second Amendment, Tenant shall deposit with Landlord the first
months rent in the amount of $7,291.91 and an additional security deposit of
$14,583.00, increasing the amount of the security deposit to be held in
accordance with Article 36 of the Lease to $57,706.25. 3.             Modifications to Definitions.  As a consequence of the leasing of the Scanticon
Expansion Space by Tenant, the following definitions appearing in the preamble
to the Lease are modified to read as follows from and after the Scanticon
Expansion Space Effective Date: (a)Lease or this
Lease consists of the Lease, Exhibits A-1 through G attached thereto and
made a part thereof, First Amendment and Exhibit H  1


attached
thereto and made a part thereof and Modification of First Amendment ofLease dated April     ,
2000 and this Second Amendment and Exhibit I attached hereto and made a
part hereof. (b)Minimum Rent
shall mean the fixed rent owed by Tenant to Landlord in the amount of
$346,237.50 per year, payable in installments of $28,853.12 per month, (c)Premises
shall mean the portion of the Building shown as the area marked on the floor
plan of the Buildings as the Medarex 6,410 square feet and the Technology
Management 4,600 square feet, a copy of which floor plan is annexed to the
Lease as Exhibit B and made a part thereof, and the portion of the
Building shown as the area marked on the floor plan of the Buildings as the
Scanticon International 3,302 square feet, a copy of which floor plan is
annexed hereto as Exhibit I and made a part hereof. (d)Rentable Area
of the Premises shall mean 14,312 square feet for the purposes of the Lease. (e)Tenants
Proportionate Share shall mean 37.70 percent. (f)Base Year shall mean 1999 for the initial Term of this Lease, 2005 for
theFirst Option Period, if any, and 2010 for the Second Option Period, if
any. 4.             Other Lease Modifications.  As a further consequence of the leasing of the
Scanticon Expansion Space by Tenant, the following provisions of the Lease are
modified to read as follows from and after the Scanticon Expansion Space
Effective Date: (a)The Basic Lease
Information cover sheet is modified to read in full as the same appears as Exhibit J
attached hereto and made a part hereof. (b)The first
sentence of Section 1.2 of the Lease is modified to read in full as
follows:  The leasing of the Premises to
and by Tenant includes the non-exclusive right to the use of sixty (60)
automobile parking spaces. 5.             Scanticon Expansion Space Effective Date.  Tenant acknowledges that the Scanticon Expansion
Space is presently occupied by Scanticon International (SI) and that SIs
lease term expires on August 31, 2000. 
In the event Landlord is unable to deliver possession of the Scanticon
Expansion Space an September 1, 2000 as a result of SI holding over, such
failure shall not affect the validity of this Second Amendment.  Landlord shall not be liable for any damages
which Tenant may incur as a result of the delay in obtaining possession of the
Scanticon Expansion Space.  In such
event, Landlord shall take reasonable action to acquire possession of the
Scanticon Expansion Space as soon as reasonably possible.  For the purposes of this Second Amendment,
the term Scanticon Expansion Space Effective Date shall mean the date on
which Landlord delivers possession of the Scanticon Expansion Space to Tenant,
free of all tenancies and occupancies and in broom clean condition. 6.             As Is Condition. 
Tenant acknowledges that except for the Landlords Work described below,
Landlord is not obligated to do any work to the Scanticon Expansion Space to
prepare it for Tenants occupancy. 
Tenant shall accept the Scanticon Expansion Space in its as is
condition as of the Scanticon Expansion Space Effective Date, provided,
however, that Tenant assumes no responsibility in respect to latent defects in
the Scanticon Expansion Space, the responsibility for the correction of  2


which resides in Landlord.  In addition, if Tenant notifies Landlord
within five (5) business days after the Scanticon Expansion Space
Effective Date that the Scanticon Expansion Space has been surrendered by SI in
a damaged or other condition that is inconsistent with SIs obligations with
respect to the surrender thereof (i.e., that the Scanticon Expansion Space
shall be surrendered broom clean, in as good condition as on the commencement
date of SIs lease, ordinary wear and tear, repairs and replacement by
Landlord, and alterations, additions and improvements permitted thereunder
excepted), Landlord shall, at Landlords cost and expense, immediately commence
to make such repairs, alterations, etc. as may be necessary to restore the
condition of the Scanticon Expansion Space to the condition in which it was
required to be surrendered by SI, and prosecute the completion of such repairs
with due diligence. 7.             Lease Extension.  As
an inducement for Landlord to lease Scanticon Expansion Space to Tenant, Tenant
agrees to extend the initial Term of the Lease with respect to the entire
14,312 square feet of space to the equivalent of five (5) years from
Scanticon Expansion Space Effective Date and to pay $26.50 per square foot for
the entire Premises for the period of time that the term of the Lease has been
extended with respect to the Medarex 6,410 square feet and the Technology
Management 4,600 square feet (approximately twelve and a half months, from July 13,
2004 to August 31, 2005). 8.             Modification.This Second
Amendment may not be changed orally and shall be binding upon and inure
to the benefit of the parties hereto and their respective successors, permitted
assigns and legal representatives. 9.             Effectiveness.  This
Second Amendment shall be effective only if both Tenant and Landlord shall have
signed and delivered to the other party a copy of this Second Amendment. 10.           Commission.  Tenant
represents and warrants to Landlord that Tenant has not dealt with any real
estate broker or sales representative in connection with this transaction other
than Fennelly Associates, Inc. and Keller, Dodds &
Woodworth.  Tenant shall indemnify and
hold harmless Landlord from and against all threatened or asserted claims,
liabilities, costs or damages (including reasonable attorneys fees and
disbursements) which Landlord may incur as a result of a breach of this
representation.  Landlord shall pay to
Broker a commission pursuant to a separate written agreement. 11.           Amended Lease.  Except to the extent expressly modified herein, all
of the terms and provisions of the Lease, First Amendment, and
Modification of First Amendment of Lease are hereby expressly ratified and
confirmed. IN WITNESS WHEREOF the parties have signed this Second Amendment as of
the date first written above.  LANDLORD:
  
  TENANT:McCARTHY ASSOCIATES LIMITED
  By:  Princeton Gateway
  Corporation, Inc.
  
  MEDAREX, INC./s/ John F. McCarthy, III
  
  /s/ Lisa N. DrakemanJohn F. McCarthy, III
  
  Name:
  Lisa N. DrakemanPresident
  
  Title:
  Senior Vice PresidentDated:
  June 8, 2000
  
  Dated:
  May 26, 2000  3


EXHIBIT J BASIC LEASE INFORMATION Landlord:
  
  McCarthy
  Associates Limiteda New Jersey limited partnership
  c/o John F. McCarthy, III, Esq.
  228 Alexander Street
  P.O. Box 2329
  Princeton, NJ  08543-2329Tenant:
  
  Medarex, Inc.707 State Road
  Princeton, NJ  08540Type
  of Entity:
  
  A
  corporation of the State of New JerseyDefinition:
  
  Base
  Year:  calendar Year 1999 for the
  initial TermDefinition:
  
  Commencement
  Date:  Scanticon Expansion Space
  Effective DateDefinition:
  
  Rentable Area of Building:
  37,966 rentable square feetDefinition:
  
  Rentable Area of Premises:
  14,312 rentable square feetDefinition:
  
  Tenants Proportionate Share:
  37.70%Definition:
  
  Termination
  Date:(1)
  Fifth
  anniversary of the Scanticon Expansion Space Effective Date; or(2)
  Tenth
  anniversary of the Scanticon Expansion Space Effective Date if Tenant
  exercises its first option to renew; or(3)
  Fifteen
  anniversary of the Scanticon Expansion Space Effective Date if Tenant
  exercises its second option to renewSection 1.3
  
  Number of Parking Spaces:
  Sixty (60)Section 1.3
  
  Minimum Rent Per Year:
  $346,237.50Section 1.3
  
  Minimum Rent Per Month:
  $28,853.12Article 36:
  
  Security Deposit:
  $57,706.25INITIALS:Landlord
  
  Tenant  4


THIRD AMENDMENT OF LEASE THIS THIRD AMENDMENT OF LEASE (Third Amendment) made as of this 8th
day of September, 2000 by and between: McCARTHY ASSOCIATES
LIMITED (Landlord)a New Jersey limited partnership
c/o John F. McCarthy, III
P.O. Box 2329
Princeton, NJ  08543-2329 AND MEDAREX, INC. (Tenant)a New Jersey corporation
707 State Road
Princeton, NJ  08540 WITNESS:  WHEREAS, pursuant to a certain Agreement of Lease dated July 7,
1999 (Lease), and First Amendment of Lease dated February 28, 2000 (First
Amendment) and a Second Amendment of Lease dated May 26, 2000 (Second
Amendment), Landlord leased to Tenant certain rentable office space in the
building commonly known as Princeton Gateway Corporate Campus, located at 707
State Road in Princeton, New Jersey (Building), and WHEREAS, Tenant is interested in Buckley & Therouxs existing
space consisting of 5,446 square feet of rentable space as shown on Exhibit I
hereto and referred to as B&T Expansion Space, NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and adequacy of
which are hereby acknowledged, Landlord and Tenant agree as follows: 1.Definitions.Unless otherwise defined in this instrument,
all capitalized terms used herein shall have the meanings ascribed to such
terms in the Lease. 2.Leasing,
Term and Increases in Rent and Security.Landlord hereby leases to Tenant, and Tenant
hereby leases from Landlord, the B&T Expansion Space pursuant to the terms
of this Third Amendment for a term (the B&T Term) commencing on the
B&T Expansion Space Effective Date (as defined below) and terminating on
the Termination Date, for a fixed rental payable by Tenant to Landlord of
$149,765.00 per year.  On or before
signing of this Third Amendment, Tenant shall deposit with Landlord an
additional security deposit of $24,960.83, increasing the amount of the
security deposit to be held in accordance with Article 36 of the Lease to
$82,667.08.  In addition, Tenant shall,
on or before January 2, 2001, deposit with Landlord the sum of $12,480.42
as an advance payment to be credited against the monthly installment of Minimum
Rent that will be due under the Lease for the first month of the B&T Term. 3.Modifications
to Definitions.As a
consequence of the leasing of the B&T Expansion Space by Tenant, the
following definitions appearing in the preamble to the Lease are modified to
read as follows from and after the B&T Expansion Space Effective Date:  1


(a)Lease or this
Lease consists of the Lease, Exhibits A-1 through G attached thereto and
made a part thereof, First Amendment and Exhibit H attached thereto and
made a part thereof and Modification of First Amendment of Lease dated April,
2000 ,and Second Amendment and Exhibit I attached thereto and made a
part hereof, and this Third Amendment and Exhibits K and L attached hereto. (b)Minimum Rent shall
mean the fixed rent owed by Tenant to Landlord in the amount of $496,002.50 per
year, payable in installments of $41,333.54 per month. (c)Premises
shall mean the portion of the Building shown as the area marked on the floor
plan of the Building as the Medarex 6,410 square feet, the Technology
Management 4,600 square feet, the Scanticon International 3,302 square feet and
the B&T 5,446 square feet, a part of a copy of which floor plan is annexed
to the Lease as Exhibit I and made a part thereof and a part of a copy
of which floor plan is annexed hereto as Exhibit K and made a part
hereof and thereof. (d)Rentable Area
of the Premises shall mean 19,758 square feet for the purposes of the Lease. (e)Tenants
Proportionate Share shall mean 52.04 percent. (f)Base Year
shall mean 1999 for the initial Term of this Lease with respect to the Medarex
6,410 square feet, the Technology Management 4,600 square feet, and the
Scanticon International 3,302 square feet and shall mean 2001 for the initial Term
of this Lease with respect to the B&T 5,446 square feet, and as to the
entire Premises shall mean 2006 for the First Option Period, if any, and 2011
for the Second Option Period, if any. 4.Other
Lease Modifications.As a further
consequence of the leasing of the B&T Expansion Space by Tenant, the
following provisions of the Lease are modified to read as follows from and
after the B&T Expansion Space Effective Date: (a)The Basic Lease
Information cover sheet is modified to read in full as the same appears as Exhibit L
attached hereto and made a part hereof. (b)The first
sentence of Section 1.2 of the Lease is modified to read in full as
follows:  The leasing of the Premises to
and by Tenant includes the non-exclusive right to the use of eighty (80)
automobile parking spaces. (c)The following
new Article 45 is hereby added to the Lease effective as of the B&T
Expansion Space Effective Date: ARTICLE 45 SIGNAGE 45.1Landlord
acknowledges that from and after the B&T Expansion Space Effective Date Tenant
shall be entitled, subject to compliance with the requirements of all
Governmental Authorities, and  2


subject to receipt of Landlords approval, to
identify the Building by the name Medarex or otherwise to post a sign visible
from Route 206 announcing Tenants presence in the Building. 45.2Landlord and
Tenant hereby agree to negotiate in good faith to resolve all related issues
within a period of four (4) months from the date hereof, including, by way
of illustration and not by way of limitation, the size, type and specific
location(s) of any such sign(s), procedures for the submission of plans
and specifications for Landlord approval, criteria for Landlord review and
approval, conditions mandating removal of any such sign(s) and all related
matters.  The agreements arrived at
during such negotiations will be memorialized in an addendum to this Third
Amendment. 5.B&T
Expansion Space Effective Date.Tenant acknowledges that the B&T
Expansion Space is presently occupied by Buckley & Theroux, LLC (B&T)
and that B&Ts lease term expires on February 28, 2001.  In the event Landlord is unable to deliver
possession of the B&T Expansion Space on March 1, 2001 as a result of
B&T holding over, such failure shall not affect the validity of this Third
Amendment.  Landlord shall not be liable
for any damages which Tenant may incur as a result of the delay in obtaining
possession of the B&T Expansion Space. 
In such event, Landlord shall take reasonable action to acquire
possession of the B&T Expansion Space as soon as reasonably possible.  For the purposes of this Third Amendment, the
term B&T Expansion Space Effective Date shall mean the date on which
Landlord delivers possession of the B&T Expansion Space to Tenant, free of
all tenancies and occupancies and in broom clean condition. 6.As Is
Condition.Tenant
acknowledges that Landlord is not obligated to do any work to the B&T
Expansion Space to prepare it for Tenants occupancy.  Tenant shall accept the B&T Expansion
Space in its as is condition as of the B&T Expansion Space Effective
Date, provided, however, that Tenant assumes no responsibility in respect to
latent defects in the B&T Expansion Space, the responsibility for the
correction of which resides in Landlord. 7.Lease
Extension.As an
inducement for Landlord to lease B&T Expansion Space to Tenant, Tenant
agrees to extend the term of the Lease of 19,758 square feet to the equivalent
of five (5) years and one month from the B&T Expansion Space Effective
Date and pay $27.50 per square foot for the Premises for the period of time
that Tenants lease of the Medarex 6,410 square feet, the Technology Management
4,600 square feet and the Scanticon International 3,302 square feet is extended
hereby (approximately seven (7) months, from September 1, 2005 to March 31,
2006). Modification.This Third Amendment may not be changed
orally and shall be binding upon and inure to the benefit of the parties hereto
and their respective successors, permitted assigns and legal representatives. 9.Effectiveness.This Third Amendment shall be effective only
if both Tenant and Landlord shall have signed and delivered to the other party
a copy of this Third Amendment. 10.Commission.Tenant represents and warrants to Landlord
that Tenant has not dealt with any real estate broker or sales representative
in connection with this transaction other than NAI Fennelly (f/k/a Fennelly
Associates, Inc.) and Keller, Dodds & Woodworth.  Tenant shall indemnify and hold harmless
Landlord from and against all threatened or asserted claims, liabilities, costs
or damages (including  3


reasonable attorneys fees and disbursements)
which Landlord may incur as a result of a breach of this representation.  Landlord shall pay to Broker a commission
pursuant to a separate written agreement. 11.Amended Lease.Except to the extent expressly modified
herein, all of the terms and provisions of the Lease, First
Amendment, Modification of First Amendment of Lease and Second Amendment are
hereby expressly ratified and confirmed. IN WITNESS WHEREOF the parties have signed this Third Amendment as of
the date first written above.  LANDLORD:
  TENANT:McCARTHY ASSOCIATES LIMITEDBy:Princeton Gateway Corporation, Inc.
  Its sole general partner
  MEDAREX, INC./s/ John F. McCarthy, III
  
  /s/ Donald DrakemanJohn F. McCarthy, III
  President
  Name: 
  Donald Drakeman
  Title:Dated:
  September 24, 2000
  
  
  Dated:
  September 11, 2000  4


EXHIBIT L BASIC LEASE INFORMATION Landlord:
  
  McCarthy
  Associates Limiteda New Jersey limited partnership
  c/o John F. McCarthy, III, Esq.
  228 Alexander Street
  P.O. Box 2329
  Princeton, NJ  08543-2329Tenant:
  
  Medarex, Inc.707 State Road
  Princeton, NJ  08540Type
  of Entity:
  
  A
  corporation of the State of New JerseyDefinition:
  
  Base
  Year:  Calendar year 1999 for the
  initial Term for all space other than the B&T Expansion Space, for which
  the Base Year is the calendar year 2001.Definition:
  
  Commencement
  Date:  on or about March 1,
  2001Definition:
  
  Rentable Area of Building:
  37,966 rentable square feetDefinition:
  
  Rentable Area of Premises:
  19,758 rentable square feetDefinition:
  
  Tenants Proportionate Share:
  52.04%Definition:
  
  Termination
  Date:(1)
  One
  month after the fifth anniversary of the Commencement Date; or(2)
  One
  month after the tenth anniversary of the Commencement Date if Tenant
  exercises its first option to renew; or(3)
  One
  month after the fifteen anniversary of the Commencement Date if Tenant
  exercises its second option to renewSection 1.3
  
  Number of Parking Spaces:
  Eighty (80)Section 1.3
  
  Minimum Rent Per Year:
  $496,002.50Section 1.3
  
  Minimum Rent Per Month:
  $41,333.54Article 36:
  
  Security Deposit:
  $82,667.08INITIALS:Landlord
  
  Tenant  5


FOURTH AMENDMENT OF
AGREEMENT OF LEASE  THIS FOURTH AMENDMENT TO THE AGREEMENT OF LEASE (the Fourth
Amendment) is made and entered into effective as of November 30, 2000 by
and between MEDAREX, INC., 707 State Road, Suite 206,
Princeton, NJ 08540, USA (Tenant) and MCCARTHY ASSOCIATES LIMITEDa New Jersey limited
partnership, c/o John F. McCarthy, III, P.O. Box 2329, Princeton, NJ
08543-2329 (Landlord).  Capitalized
terms used in this Amendment that are not otherwise defined herein shall have
the same meanings as such terms are defined in the Agreement (as defined
below). A.Tenant and Landlord entered into a
Agreement of Lease dated July 7, 1999 (the Lease), and a First Amendment
of Lease dated February 28, 2000 (First Amendment) and a Second
Amendment of Lease dated May 26, 2000 (Second Amendment), and a Third
Amendment of Lease dated September 24, 2000 (Third Amendment)
(collectively, the Lease and its amendments are the Agreement), and Landlord
leased to Tenant certain rentable office space in the building commonly known
as Princeton Gateway Corporate Campus, located at 707 State Road in Princeton,
New Jersey (Building). B.The Parties desire to amend the terms of
the Agreement in order update the Notices provision. NOW,
THEREFORE,the
Parties agree as follows: 1.Amendment of the Lease. The Parties hereby
agree to amend the terms of the Agreement as provided below. 1.1Notices, copy.The name and address of Sattlerlee Stephens Burke & Burke LLP
in Article 25 are hereby deleted and shall be replaced with the following: Medarex, Inc.
707 State Road, Suite 206
Princeton, NJ  08540
Att:  General Counsel 1.2Notices, to Tenant.The address of Medarex, Inc. in Article 25 is hereby deleted
and shall be replaced with the following: 707 State Road, Suite 206
Princeton, NJ  08540
Att:  Donald L. Drakeman, President and
CEO  1


1.3          Notices, to Landlord.The address of McCarthy Associates Limited in Article 25 is hereby
deleted and shall be replaced with the following: c/o John F. McCarthy, III
731 Alexander Road
P.O. Box 2329
Princeton, NJ  08543-2329 2.             Miscellaneous. 2.1          No Other Changes.Except as expressly provided in this Fourth Amendment, all terms of the
Agreement shall remain in full force and effect. 2.2          Counterparts.This Fourth Amendment may be executed in two or more counterparts, each of
which shall be deemed an original, but both of which together shall constitute
one and the same instrument. IN
WITNESS WHEREOF,the parties have caused this Fourth Amendment to be executed by their
respective authorized officers.  MEDAREX,
  INC.
  
  MCCARTHY
  ASSOCIATES LIMITED
  By:  Princeton Gateway Corporation, Inc.By:
  /s/ W. Bradford
  Middlekauff
  
  By:
  /s/ John F.
  McCarthy, IIIName:  W. Bradford Middlekauff
  
  Name:  John F. McCarthy, IIITitle:  Vice President and General Counsel
  
  Title:  President  Date:
  11/22/00
  
  Date:
  11/30/00  2


FIFTH AMENDMENT OF LEASE THIS FIFTH AMENDMENT OF LEASE (Fifth Amendment)
made on this 23rd day of May, 2005 by and between: MCCARTHY ASSOCIATESLIMITEDa New Jersey limited partnership87 Ettl Circle
Princeton, NJ 08540
(Landlord) AND MEDAREX, INC.707 State Road
Princeton, NJ   08540
(Tenant) RECITALS: WHEREAS, pursuant to a certain lease dated July 7,
1999 (Lease) modified by a First Amendment to Lease dated February 28,
2000 (First Amendment), a Second Amendment to Lease dated May 26, 2000 (Second
Amendment), a Third Amendment to Lease dated September 8, 2000 (Third
Amendment) and a Fourth Amendment to Lease dated November 30, 2000 (Fourth
Amendment), Landlord leased to Tenant 19,758 square feet of office space (Premises)
in the building commonly known as 707 State Road (Building) for an initial
term ending March 31, 2006; and WHEREAS, Tenant and Landlord now desire to amend the
Lease as of April 1, 2006 and to extend the term of the Lease for a term
of seven years from April 1, 2006 to March 31, 2013; NOW, THEREFORE, in consideration of the mutual
covenants contained herein and other good and valuable consideration, the
receipt and adequacy of which are hereby acknowledged, Landlord and Tenant
agree as follows: 1.Term.Subject to the provisions of this Fifth
Amendment, Landlord and Tenant hereby extend the term of the Lease through March 31,
2013. 2.Defined Terms.As of April 1,
2006, the Lease shall be amended as follows: 2.1The term Lease or this Lease (as used in the Lease) consists of the
Lease, Exhibits A-1 through G attached thereto and made a part thereof,
First  1


Amendment
and Exhibit H attached thereto, Second Amendment and Exhibit I
attached thereto and made a part hereof, Third Amendment and Exhibits K and L
attached thereto, Fourth Amendment, and this Fifth Amendment and Exhibit M
attached hereto. 2.2The term Minimum Rent (as used in the Lease) and the term Minimum Rent
Per Year (as used in the Basic Lease Information Sheet) shall mean the fixed
rental payable by Tenant to Landlord in the following amounts;  First
  Year (4/1/06 to 3/31/07):
  $434,676.00
  ($22.00/sq.ft.)Second
  Year (4/1/07 to 3/31/08):
  $444,555.00
  ($22.50/sq.ft.)Third
  Year (4/1/08 to 3/31/09):
  $454,434.00
  ($23.00/sq.ft.)Fourth
  Year (4/1/09 to 3/31/10):
  $464,313.00
  ($23.50/sq.ft.)Fifth
  Year (4/1/10 to 3/31/11):
  $474,192.00
  ($24.00/sq.ft.)Sixth
  Year (4/1/11 to 3/31/12):
  $484,071.00
  ($24.50/sq.ft.)Seventh
  Year (4/1/12 to 3/31/13):
  $493,950.00
  ($25.00/sq.ft.)
  2.3The term Base
Year (as used in the Lease and in the Basic Lease Information Sheet) shall
mean 2005. 2.4The term Base
Charge (as used in the Lease) shall mean Tenants Proportionate Share of
Taxes. 2.5The term Minimum
Rent Per Month (as used in the Basic Lease Information Sheet) shall mean as
follows: First
  Year:
  $ 36,223.00Second
  Year:
  $ 37,046.25Third
  Year:
  $ 37,869.50Fourth
  Year:
  $ 38,692.75Fifth
  Year:
  $ 39,516.00Sixth
  Year:
  $ 40,339.25Seventh
  Year:
  $ 41,162.50  2.6The term Termination
Date  (as used in the Lease and in
the Basic Lease Information Sheet) shall mean March 31, 2013, or such
earlier date upon which the Lease may expire or be terminated pursuant to any
provision of the Lease or pursuant to law.  3.Other
Lease Modifications.  The following
provisions of the Lease are modified from and after April 1, 2006:  2


3.1The Basic Lease
Information cover sheet is modified to read in full as it appears as Exhibit M
attached to and made a part hereof. 3.2Article 6
of the Lease is modified to eliminate any requirement that Tenant pay Landlord
its Proportionate Share of any increase in Landlords Operating Expenses.   As such, all references in the Lease to
Landlords Operating Expenses (including but not limited to the reference in
the definition of Projected Expenses in Section 6.3), are eliminated and
Sections 6.1.2 and 6.8 of the Lease are deleted in their entirety, such that
the provisions of Sections 6.1 through 6.12, inclusive, shall apply solely to
Taxes.  Tenant shall pay Landlord its
Proportionate Share of the increase in Taxes over the Base Charge. 3.3In addition,
the following provisions shall be added to Article 6: ARTICLE 6 ADDITIONAL RENT 6.13Effective April 1,
2006 Tenant shall pay to Landlord, as Additional Rent, the following: First Year:
  $50,382.90/year
  ($2.55/sq.ft.) or $4,198.57/monthSecond Year:
  $51,765.96/year
  ($2.62/sq.ft) or $4,313.83/monthThird Year:
  $53,451.21/year
  ($2.71/sq.ft) or $4,454.27/monthFourth Year:
  $55,054.75/year
  ($2.79/sq.ft.) or $4,587.90/monthFifth Year:
  $56,705.46/year
  ($2.87/sq.ft.) or $4,725.45/monthSixth Year:
  $58,407.58/year
  ($2.96/sq.ft.) or $4,867.30/monthSeventh Year:
  $60,064.32/year
  ($3.04/sq.ft.) or $5,005.36/month  6.14Tenant shall pay the
Additional Rent required by Section 6.13 in equal monthly installments on
the first day of each calendar month,  3


in advance, commencing April 1, 2006 during the then remaining
term of this Lease. 3.4           The payment of Additional Rent
pursuant to Sections 6.13 and 6.14 of the Lease shall constitute Tenants
payment of electrical energy as required by Article 15 of the Lease.  Accordingly, effective April 1, 2006, Article 15
of the Lease is hereby amended as follows: 3.4.1        The phrase [a]s part of Landlords
Operating Expenses, is deleted from the first sentence of Section 15.1. 3.4.2        The words this paragraph 15.2 in the
first sentence of Subsection 15.2.1 are hereby changed to Sections 6.13 and
6.14. 3.4.3        Clause (iii) of the first sentence
of Subsection 15.2.1, which begins Tenant agrees and the ensuing eight (8) sentences
through the words decrease or tax; (iv) are hereby deleted in their entirety. 3.4.4        The words the amount of $1.25 per
square foot in Subsection 15.2.5 are hereby changed to the Additional Rent
required by Section 6.13. 3.5           Anything in the Lease to the contrary
notwithstanding, there shall be solely three components of Tenants Rent:
first, the Minimum Rent set forth in Section 2.2 of this Fifth Amendment;
second, the Additional Rent set forth in Section 3.3 above (new Section 6.13
of the Lease); and third, Tenants Proportionate Share of the increase, if any,
in Taxes over the Base Year. 4.             Finish Work. 4.1           Tenant shall submit to Landlord for
Landlords review and approval schematic drawings showing proposed improvements
to the Premises desired by Tenant to improve the Premises for Tenants
occupancy (Schematic Drawings). Tenant shall determine what improvements
should be done to the Premises and same shall be included in such Schematic
Drawings for Landlords approval, which approval shall not be unreasonably
withheld, conditioned or delayed.  If
Landlord shall not approve of the Schematic Drawings as submitted by Tenant,
Landlord shall notify Tenant thereof within five (5) business days after
receipt of the Schematic Drawings specifying in said notice the particulars of
such revisions therein as are reasonably requested by Landlord for the purpose
of obtaining its approval.  Within five (5) business
days after being so informed by Landlord,  4


Tenant
shall submit to Landlord, for Landlords approval (which approval shall not be
unreasonably withheld, conditioned or delayed) revised Schematic Drawings
incorporating such revisions or such modifications thereof as were reasonably
requested by Landlord and as are acceptable to Tenant.  Within three (3) business days after
receipt thereof, Landlord shall notify Tenant whether such revised Schematic
Drawings are approved, which approval shall not be unreasonably withheld,
conditioned or delayed; and if not approved, Landlord shall specify in writing
the particulars of any such items not approved. 
The provisions of the immediately preceding two (2) sentences shall
be repeated until Landlord has approved Schematic Drawings acceptable to Tenant
(said Schematic Drawings, as so approved, are hereinafter referred to as the Final
Schematics).  After approval of the
Final Schematics Tenant shall cause to be prepared architectural working
drawings and specifications for the layout and finish of the proposed
improvements and shall submit them to Landlord for its review and approval
(which shall not be unreasonably withheld, conditioned or delayed).  Said working drawings and specifications
shall be reasonably consistent with the Final Schematics (other than for minor
deviations), shall be consistent with the design and construction of the
Building and shall not materially interfere with or disrupt any of the other
equipment in the Building.  If Landlord
shall not approve of the working drawings and specifications as submitted by
Tenant, Landlord shall notify Tenant thereof within five (5) business days
after receipt of the working drawings and specifications specifying in said
notice the particulars of such revisions therein as are reasonably requested by
Landlord for the purpose of obtaining its approval.  Within five (5) business days after
being so informed by Landlord, Tenant shall submit to Landlord, for Landlords
approval (which approval shall not be unreasonably withheld, conditioned or
delayed), revised working drawings and specifications incorporating such
revisions or such modifications thereof as were reasonably requested by
Landlord and as are acceptable to Tenant. 
Within three (3) business days after receipt thereof, Landlord
shall notify Tenant whether such revised working drawings and specifications
are approved, which approval shall not be unreasonably withheld, conditioned or
delayed; and if not approved, Landlord shall specify in writing the particulars
of any such items not approved.  The
provisions of the immediately preceding two (2) sentences shall be repeated
until Landlord has approved working drawings and specifications acceptable to
Tenant (said drawings and specifications, as so approved, are hereinafter
referred to as the Working Drawings and the work shown thereon is hereinafter
referred to as the Finish Work). 
Tenant shall provide Landlord with copies of receipts for all work
performed and fixtures purchased as part of such Finish Work.  The cost to prepare Schematic Drawings, Final
Schematics and Working Drawings shall be included in the cost of the Finish
Work. 4.2           Promptly after Tenants receipt of
all required governmental permits and approvals for the construction of the
Finish Work, Tenant shall commence the  5


construction of the Finish
Work through a (1) construction manager and (2) contractor or
contractors. Tenant shall select and engage such construction manager and
contractors.  Tenant shall proceed with
such construction with due dispatch to cause the Finish Work to be constructed
in accordance with the Working Drawings in a good and workmanlike manner and in
accordance with all applicable laws, orders and regulations of Governmental
Authorities, and to use first quality materials.  The costs associated with the employment and
retention of a construction manager shall be included in the cost of the Finish
Work. 4.3Each phase of
the Finish Work shall be deemed completed on the day following Tenants notice
to Landlord that (i) the Finish Work is substantially completed, and (ii) Tenant
has obtained either a permanent or temporary certificate of occupancy for the
Finish Work. 4.4Promptly after
the completion of each phase (as defined in the specifications constituting
part of the Working Drawings) of the Finish Work, Landlord shall pay to Tenant,
or at Tenants election to Tenants contractors, the cost of such completed
phase of the Finish Work.  Landlords
obligation under this paragraph is limited to an aggregate maximum payment of
$100,000.00.  If the aggregate cost of
the Finish Work exceeds $100,000.00, Tenant shall be responsible for the all
costs in excess of $100,000.00. By way of example, if the cost of the Finish
Work (including architectural fees and costs of the construction manager) is
$90,000.00, Landlord shall pay Tenant (or Tenants contractors)
$90,000.00.  If the cost of such Finish
Work is $110,000.00, Landlord shall pay Tenant (or Tenants contractors)
$100,000.00. Tenant shall provide to Landlord at the time of each request for
payment an AIA form (such as G702) reasonably acceptable to Landlord setting
forth the Finish Work completed and the amount requested to be paid. 5.Option
to Lease Additional Space. 5.1As long as (1) Tenant
is not in default under the Lease beyond any applicable grace period; and (2) space
in the Building becomes available for lease prior to the Termination Date,
Landlord shall first notify Tenant that such additional space is available by
giving Tenant written notice (a Leasing Availability Notice) specifying the
date of availability of such space and sending Tenant an addendum to the Lease
whereby Tenant may lease the additional space in accordance with the provisions
of this Fifth Amendment.  Within ten (10) calendar
days of Tenants receipt of such Leasing Availability Notice, Tenant shall
notify Landlord whether or not Tenant elects to lease the additional space
pursuant to this paragraph.  In the event
Tenant elects to so lease the additional space, Tenant shall execute and
deliver to Landlord the addendum to the Lease  6


whereby Tenant shall lease
the additional space for a term to expire on the Termination Date. 5.2All of the
terms, covenants and conditions of this Lease shall apply to and pertain to
such additional space except that the Minimum Rent shall be computed in the
manner set forth in Exhibit F of the Lease and the Additional
Rent shall be as set forth for the appropriate year in Section 3.3 above
(new Section 6.13 of the Lease). 
For example, the Additional Rent for this additional space during the
period 4/1/08 to 3/31/09 shall be $2.71/sq.ft./annum, prorated for the period
actually leased. 6.Option
to Purchase the Building.As long as (1) Tenant
is not in default under the Lease beyond any applicable grace period; and (2) the
Building becomes available for sale prior to the Termination Date, Landlord
shall first notify Tenant that the Building is available for sale by giving
Tenant written notice (a Sale Availability Notice) proposing the price, terms
and other conditions of such sale. 
Within ten (10) calendar days of Tenants receipt of such Sale
Availability Notice, Tenant shall notify Landlord (Tenants Notice) whether
Tenant (i) elects to buy the Building at the price and upon the terms and
conditions set forth in the Sale Availability Notice, (ii) would be
willing to buy the Building for a different price and/or upon different terms
and conditions or (iii) elects not to buy the Building. 6.1In the event
Tenant elects not to buy the Building Landlord shall be free for a period of
twelve (12) months to sell the Building at a price and upon terms and
conditions no more favorable to the purchaser than those offered to Tenant in
the Sale Availability Notice, free and clear of Tenants rights under this Section 6.  In the event the Landlord is unable to sell
the Building within such twelve (12 month) period or in the event Landlord
offers to sell the Building during such period at a price or upon terms and
conditions more favorable to the purchaser than those offered to Tenant in the
Sale Availability Notice, the provisions of this Section 6 shall
immediately spring back into effect and the Landlord shall immediately be
required to deliver to the Tenant a new Sale Availability Notice containing
such more favorable to the purchaser price, terms and conditions, whereupon
Tenant shall once again be entitled to all of the rights and privileges
provided under this Section 6. 6.2In the event
Tenant elects to buy the Building at the price and upon the terms and
conditions set forth in the Sale Availability Notice, Tenant shall within five (5) business
days after delivery of the Tenants Notice prepare, execute and deliver to
Landlord a contract whereby Tenant shall purchase the Building for the price and
upon the terms and conditions set forth in the Sale Availability Notice. Landlord shall
thereupon execute the said contract and deliver a fully executed  7


copy to Tenant within five (5) business
days after Landlords receipt of the contract. 6.3In the event
Tenant desires to buy the Building for a different price and/or upon different
terms and conditions than those set forth in the Sale Availability Notice,
Tenants Notice shall set forth such price and/or other terms and conditions (Tenants
Terms). If Landlord shall not approve of the Tenants
Terms, Landlord shall notify Tenant thereof within five (5) business days
after receipt of the Tenants Terms specifying in said notice the particular
revisions requested by Landlord for the purpose of obtaining its approval.  Within five (5) business days after
being so informed by Landlord, Tenant shall submit to Landlord revised Tenants
Terms incorporating such revisions or such modifications thereof as were
requested by Landlord and as are acceptable to Tenant.  Within three (3) business days after
receipt thereof, Landlord shall notify Tenant whether or not such revised
Tenants Terms are approved. 6.3.1If at any time
Landlord approves Tenants Terms (as theretofore revised by Tenant), Tenant
shall within five (5) business days thereafter execute and deliver to
Landlord a contract whereby Tenant shall purchase the Building upon Tenants
Terms (as so revised).  Landlord shall
thereupon execute the said contract and deliver a fully executed copy to Tenant
within five (5) business days after Landlords receipt of the contract
executed by Tenant.  In the event Tenant
elects not to buy the Building Landlord shall be free to sell the Building at
such price and upon such terms and conditions as Landlord may desire, free and
clear of Tenants rights under this Section 6. 6.3.2In the event
Landlord and Tenant are unable to agree upon a price or terms and conditions
for the sale of the Building within the time period permitted under this
Subsection 6.3, Landlord shall be free for a period of twelve (12) months to
sell the Building at a price and upon terms and conditions no more favorable to
the purchaser than those contained in the Tenants Terms (as theretofore revised),
free and clear of Tenants rights under this Section 6.  In the event the Landlord is unable to sell
the Building within such twelve (12 month) period at a price and upon terms and
conditions no more favorable to the purchaser than those contained in the
Tenants Terms (as theretofore revised) or in the event Landlord offers to sell
the Building during such period at a price or upon terms and conditions more
favorable to the purchaser than those contained in the Tenants Terms (as
theretofore revised), the provisions of this Section 6 shall immediately
spring back into effect and the Landlord shall immediately be required to
deliver to the Tenant a new Sale Availability Notice containing such more
favorable to the purchaser price, terms and  8


conditions, whereupon Tenant
shall once again be entitled to all of the rights and privileges provided under
this Section 6. 7.Modification.This Fifth Amendment may not be changed
orally and shall be binding upon and inure to the benefit of the parties hereto
and their respective successors, permitted assigns and legal representatives. 8.Effectiveness.This Fifth Amendment shall be
effective only if both Tenant and Landlord shall have signed and delivered to the
other party a copy of this Fifth Amendment. 9.Commission.Landlord represents and warrants
to Tenant that it has not dealt with any real estate broker or sales
representative in connection with this Fifth Amendment other than Jerry
Fennelly of NAI Fennelly and Buzz Woodworth. Tenant represents and warrants to
Landlord that it has not dealt with any real estate broker or sales
representative in connection with this Fifth Amendment.  Each party shall indemnify and hold harmless
the other party from and against all threatened or asserted claims,
liabilities, costs or damages (including reasonable attorneys fees and
disbursements) which that other party may incur as a result of a breach of this
representation.  Landlord acknowledges
that Landlord may be obligated to Jerry Fennelly of NAI Fennelly and to Buzz
Woodworth or another lawful successor-in-interest to the firm of Keller, Dodds
and Woodworth in connection with this Fifth Amendment and agrees to be
responsible for any commissions or other compensation that may become due to
Jerry Fennelly and/or NAI Fennelly (or any successor entity) and to Keller,
Dodds and Woodworth (or any successor entity) and/or Buzz Woodworth arising out
of this Fifth Amendment. 10.Ratification.Except to the extent expressly modified
herein, all of the terms and provisions of the Lease, First Amendment, Second
Amendment, Third Amendment and Fourth Amendment are hereby expressly ratified
and confirmed. [SIGNATURES APPEAR ON NEXT PAGE.]  9


IN WITNESS WHEREOF, the parties have signed this
Fifth Amendment as of the date written below. LANDLORD MCCARTHY
ASSOCIATES LIMITED By: Princeton Gateway Corporation, Inc. Its sole corporate general partner  Dated:
  May 23, 2005
  
  By:
  /s/
  John F. McCarthy, IIIJohn
  F.  McCarthy III, as its PresidentTENANTMEDAREX, INC./s/
  Christian S. SchadeDated:  May 20, 2005
  
  Name:
  Christian
  S. SchadeTitle:  Chief Financial Officer
  10


EXHIBIT M BASIC LEASE INFORMATION Landlord:
  McCarthy
  Associates Limited
  87 Ettl Circle
  Princeton, NJ   08540Tenant:
  Medarex, Inc.
  707 State Road
  Princeton, NJ   08540Base
  Year:
  2005Definition
  Commencement
  Date of Fifth Amendment: April 1, 2006Definition
  Rentable
  Area of Building:
  37,966
  rentable square feetDefinition
  Rentable
  Area of Premises:
  19,758
  rentable square feetDefinition
  Tenants
  Proportionate Share:
  52.04%Definition
  Termination
  Date:
  March 31,
  2013 (seven years)Section 1.3
  Number
  of Parking Spaces:
  80
  spacesSection 1.3
  Minimum
  Rent Per Year:First
  Year (4/1/06-3/31/07):
  $434,676.00
  ($22.00/sq.ft.)Second
  Year (4/1/07-3/31/08):
  $444,555.00
  ($22.50/sq.ft.)Third
  Year (4/1/08-3/31/09):
  $454,434.00
  ($23.00/sq.ft.)Fourth
  Year (4/1/09-3/31/10):
  $464,313.00
  ($23.50/sq.ft.)Fifth
  Year (4/1/10-3/31/11):
  $474,192.00
  ($24.00/sq.ft.)Sixth
  Year (4/1/11-3/31/12):
  $484,071.00
  ($24.50/sq.ft.)Seventh
  Year (4/1/12-3/31/13):
  $493,950.00
  ($25.00/sq.ft.)
  Section 1.3
  Minimum
  Rent Per Month:First
  Year:
  $ 36,223.00Second
  Year:
  $ 37,046.25Third
  Year:
  $ 37,869.50Fourth
  Year:
  $ 38,692.75Fifth
  Year:
  $ 39,516.00Sixth
  Year:
  $ 40,339.25Seventh
  Year:
  $ 41,162.50Article 36
  Security
  Deposit:
  $82,667.08
  INITIALS:Landlord
  
  Tenant
  11