Exhibit 10.40  LEASE
AMENDMENT NO. 1  LEASE AMENDMENT made as of this 15th day of July 1993 to that certainLease Agreement dated as of May 6, 1993 (Agreement) between EXXON
RESEARCH AND ENGINEERING COMPANY (Landlord) and MEDAREX, INC. (Tenant).  WHEREAS, the parties desire to amend the
Agreement to add additional space to the Demised Premises;  NOW THEREFORE, the parties agree that the
Agreement is hereby amended as follows:  1. Section 1.01(a) is amended to
read as follows:  Agreement. The Lease Agreement dated as of May 6,
1993 between Landlord and Tenant, as amended by Lease Amendment No. 1
dated as of July 15, 1993.  2. Section 1.01(d) is amended to
read as follows:  Demised Premises. Those portions of the
Building hereby leased to Tenant commonly known as Level 1 of the southwest
quadrant (LF/LH-l) of the laboratory facilities, as more particularly
depicted on Exhibit B-3 annexed hereto, including the LF atrium as shown
on Exhibit N annexed hereto, together with that proportionate share of the
mechanical rooms in the LF/LH penthouse and that portion of the cylinder
storage area in the LF/LH penthouse which serve LF/LH-1, and the proportionate
share of the mechanical space on Level 0
of the LF/LH wing, all of which are deemed to be 37,200 rentable square
feet.  The portions of the Demised Premises within
the Building shall also include the laboratory furniture, laboratory casework,
incidental furniture, fixtures, hoods, equipment, shades, draperies, carpeting
and office furniture and the like in place as of the commencement of this
Agreement and identified in Exhibits B-2 and B-4 annexed hereto.  3.Exhibit B-1 is
deleted and replaced by Exhibit B-3 annexed hereto and made a part
hereof.  Exhibit B-4 is added to
this Agreement and made a part hereof.  4.Section 2.01 DEMISED
PREMISES AND TERM is amended toread as
follows:


Landlord hereby leases to Tenant and Tenant
hereby hires and takes from Landlord the Demised Premises for the term of
sixty-three (63) months commencing at 12:01 a.m. on the fifteenth (15th)
day of July, 1993 and expiring at 12:00 midnight on the fourteenth (14th) day
of October, 1998, unless this Agreement is sooner terminated as hereinafter
provided.  5.Section 4.02(5) is
amended by the deletion of July 1, 1993 and the substitution therefor of July 15,
1993.  6.The first paragraph of Section 5.01
RENT is amended to read as follows:  Rent for the demised term shall be Four
Million Eight Hundred Thirty Six Thousand Dollars ($4,836,000) reflecting
abatements set forth below in this Section, payable at the rate of Eighty
Thousand Six Hundred Dollars ($80,600) per month for the period October 15,
1993 through October 14, 1998, which sum shall be the Basic Monthly
Rental.  7.The last paragraph of Section 5.01
RENT is amended to read as follows:  Notwithstanding the foregoing, Tenants
obligation to pay Basic Monthly Rental shall be abated for three (3) months
until October 15, 1993, with the effect that Tenant shall not be obligated
to pay any Basic Monthly Rental from July 15 through September 15,
1993. This abatement shall not apply to Tenants obligation to pay Additional
Rent, nor shall it apply to Tenants obligation to pay for Optional Services.  8.Sections 6.02(a) &
(d) are amended by the deletion of 2.5% and the substitution therefor of
4.8%.  9.Section 6.03 OPERATING
EXPENSES is amended by the deletion of Exhibit E and the
substitution therefor of Exhibit M, wherever it appears. Exhibit E
is deleted and replaced by Exhibit M - Operating Expenses for Operating
Base Year 1993, annexed hereto and made a part hereof.  10.Section 6.05 UTILITY
CHARGES is amended by the deletion of July 1, 1993 and the
substitution therefor of July 15, 1993; by the deletion of Sixty and
No/l00 Dollars ($60) and the substitution therefor of One Hundred Twenty and
No/l00 Dollars ($120); by the deletion of Exhibit F-l and the
substitution therefor of Exhibit F-5; and by the deletion of Exhibit F-3
and the substitution therefor of Exhibit F-6, wherever the same appear.
Sections 6.05(b) and (c) are amended by the deletion of LF-l and
the substitution therefor of LF/LH-l, wherever it appears. Section 6.05(c) is
amended by the deletion of 2,000 and the substitution therefor of
4,000.  Section 6.05(e) is
amended by the deletion of 1,000 and the substitution


therefor of 2,000 wherever it appears.  11.Exhibits F-1 and F-3 are
deleted and replaced by Exhibits F-5
and F-6 annexed hereto and made a part hereof.  12.Section 9.01 is amended to provide that
Landlord will, upon the request of Tenant, remove from the Demised Premises any
fume hoods currently located therein, as designated by Tenant, provided that
any such requests are made by January 31, 1994.  13.Section 11.03 PROPERTY DAMAGE is
amended by the deletion of 2.5% and the substitution therefor of 4.8%.  14.Section 11.06 EXCLUSIONS, Section 18.02
CHEMICAL STOCKROOM and Section 34.01 SURRENDER OF PREMISES
are amended by the deletion of ECRA and the substitution therefor of ISRA.  15.Exhibit G LETTER OF CREDIT AGREEMENT
is amended as follows:  a. Paragraph 2 is amended by the deletion of(i) $675,000 and the substitution therefor of
$1,260,000, (ii) $168,750
and the substitution therefor of $315,000, and (iii) $57,000 and the substitution therefor of
$102,000.  b.Paragraph 3 is amended by the deletion of July 1, 1993 and the
substitution therefor of July 15, 1993.  c.Schedule A FORM OF IRREVOCABLE LETTER OF CREDIT is amended by
the deletion of (i) Six Hundred Seventy-five Thousand Dollars($675,000)
and $675,000 andthe substitution therefor of One Million Two
Hundred Sixty Thousand Dollars
($1,260,000) and $1,260,000, (ii) $168,750 and the substitution therefor of $315,000, and (iii) $57,000 and the substitution therefor of
$102,000.  16.Article 17
is amended by the deletion of the terms (a) Environmental Clean-up
Responsibility Act and ECRA and the substitution therefor of Industrial
Site Recovery Act and ISRA, and (b) Cleanup Plan and the substitution
therefor or of Remedial Action Workplan.  17.Section 17.06
ADMINISTRATIVE CONSENT ORDER is amended by the deletion of bond and
the substitution therefor of funding source, wherever it appears.  18.Section 25.01
ACCESS AND RIGHT OF INSPECTION is amended by the deletion of LF-l and
July 1, 1993 and the substitution therefor of LF/LH-l and July 15,
1993.


19.Section 31.01
SUBORDINATION is amended by the deletion of the second sentence.  20.Exhibit L is
deleted.  21.Section 32.02
PERSONAL LIABILITY OF LANDLORD is amended by the addition of the
following phrase on the third line after equity,: but excepting the
provisions to the contrary in Section 34.01 . . .  22.Section 34.01
QUIET ENJOYMENT is amended to read as follows:  Landlord
covenants that if, and so long as, Tenant pays the Basic Monthly Rental and
Additional Rent as herein provided, and keeps, observes and performs each and
every term of this Agreement on Tenants part to be kept, observed and
performed, Landlord shall do nothing to affect Tenants right to peaceably and
quietly have, hold and enjoy the Demised Premises for the term herein
mentioned, subject to the provisions of this Agreement and to the provisions of
any superior mortgage. Landlord specifically covenants andagrees that Tenants right to
peaceably and quietly have, hold and enjoy the Demised Premises for the term
herein mentioned shall not be affected in any adverse manner by reason of any
breach by Tenant of the provisions of the Main Lease, and Landlord hereby
agrees to indemnify, defend and hold harmless the Tenant from any claim or
liability to the OverLandlord or any other party by reason of Tenants breach
of the provisions of the Main Lease. The limitation of liability of Landlord,
pursuant to the provisions of Section 32.02, shall not apply to this
covenant and indemnification of Landlord with respect to performance of the
terms of the Main Lease, or to any damages suffered by Tenant arising out of
any breach of the provisions of the Main Lease by Landlord, it being understood
that, if Tenants peaceable and quiet enjoyment of the Demised Premises is
disturbed by reason of a breach by Landlord of the terms of the Main Lease,
Landlord shall be fully and personally liable to Tenant for all damages resulting
from such breach and recoverable by law.  23.Section 41.01
RENEWAL OPTION is amended by the de1etion of (a) July 1,
1993 and the substitution therefor of July 15, 1993, (b) October 1,
1998 and the substitution therefor of October 15, 1998, and (c) September 30,
2003 and the substitution therefor of October 14, 2003.  24.Section 42.01
PARKING is amended by the deletion of one (1) and the substitution
therefor of two (2).  25.Section 43.01
SIGNS is amended by the deletion of LF-l and


the substitution therefor of LF/LH-l.  26.The index to Exhibits
appearing on page vi of the Agreement is deleted.  27.Except and as amended hereby,
the Agreement remains in full force and effect.  IN WITNESS WHEREOF, Landlord and Tenant have
caused this Lease Amendment No. 1 to be duly executed as of the date
provided on Page 1 of this agreement.  LANDLORD: EXXON RESEARCH AND ENGINEERING COMPANY  By
  /s/ Frank B. SprowFrank B. SprowVice PresidentDATED:
  July 15, 1993TENANT:MEDAREX, INC.By
  /s/Michael AppelbaumMichael AppelbaumVice President and CFODATED:
  July 15,
  1993


LEASE AMENDMENT NO. 2  LEASE AMENDMENT made as of this 23 day of
September, 1994 to that certain Lease Agreement dated as of May 6, 1993
(Agreement) between EXXON RESEARCH AND ENGINEERING COMPANY (Landlord) and
MEDAREX, INC. (Tenant).  WHEREAS, the parties desire to amend the
Agreement to add additional space to the Demised Premises;  NOW, THEREFORE, the parties agree that the
Agreement is hereby amended as follows:  1.The
Demised Premises as defined in Section 1.01(d) of the Agreement are
enlarged effective October 1, 1994 by the addition of that portion of the
3rd floor of the Central Functions Wing (CC-3) depicted on Exhibit A
attached hereto and deemed to be 7,368 rentable square feet, inclusive of the
offices that are commonly known by the following designations:  CC323, CC324, CC327, CC328, CC329, CC330,
CC330A, CC334, CC334A, CC333, CC335, CC338, CC338A, CC339, CC341, CC342,
CC342A, CC343, CC344, CC346, CC396, CC397.  The portion of CC-3 that is the subject of this Lease Amendment No. 2
shall hereinafter be referred to as CC323-397.  2.Tenant
acknowledges that it has thoroughly examined CC323-397 and takes said space in
its AS IS condition as of October 1, 1994 subject only to Landlords
Work. In CC323-397, Landlord shall (i) shampoo all carpeting, (ii) remove
all furniture except the furniture in conference room CC329, (iii) remove
all stored items from hallways, (iv) patch and paint as required, (v) repair
broken building equipment, if any, and (vi) enclose the atrium with
bankers partitions (together, Landlords Work).  3. Rent for CC323-397 for the demised term (October 1, 1994 to and
including October 14, 1998) shall be Six hundred seventy-eight thousand,
Four hundred sixty-seven and 94/100 Dollars ($678,467.94), payable in equal
monthly installments of Fourteen thousand, three and 00/100 Dollars
($14,003.00), prorated for partial months, which sum shall be the Basic Monthly
Rent. (For information purposes only, Basic Rent for CC323-397 is calculated on
a unit rate of $22.00 per rentable square foot per year.)  4. Additional Rent for CC323-397 for the demised term shall be
Ninety-three thousand, One hundred eighty-eight and 60/100 Dollars
($93,188.60), payable in equal monthly installments of One thousand, Nine
hundred twenty-three and33/100 Dollars ($1,923.33), prorated for partial
months- (For information purposes only, Additional Rent for CC323-397 is
calculated on a unit rate of $1.25 per rentable square foot for the entire CC-3
floor, deemed to be 18,424 square feet).


5. If the tenant occupying the 2nd floor of the Central Functions wing
advises Landlord that, notwithstanding the bankers partitions, an unacceptable
level of noise emanating on the 3rd floor is audible on the 2nd floor via the
atrium, then Landlord shall have the right to enclose the atrium in glass.
Tenant agrees that it shall bear one-half of the reasonable costs and expenses
to so enclose the atrium, but not to exceed $20,000, which amount shall be due
and payable as Additional Rent.  6. Landlord may terminate this Lease Amendment No. 2 at any time
on not less than sixty (60) days written notice to Tenant, in which event
Tenant shall quit and surrender CC323-397 to Landlord, broom clean, in good
safe order and condition, ordinary wear and tear excepted, and Tenant shall
remove all of its property therefrom.  7. Tenants entitlement to indoor parking spaces is increased by three (3) spaces,
from two (2) spaces under Lease Amendment No. 1, to five (5) spaces
under this Lease Amendment No. 2.  8. If Landlord receives a bona fide offer from a third party to lease
more space in CC-3 than is being leased by Tenant hereunder, which offer
Landlord desires to accept, Landlord shall deliver a copy of such offer to
Tenant, and Tenant may, within twenty (20) business days thereafter, elect to
lease the subject space on the same terms as those set forth in the offer. If
Tenant does not accept such offer, Tenants rights under this Paragraph 8 shall
be extinguished, and Landlord may notify Tenant of termination under this Lease
Amendment No. 2 and lease the subject space to such third party. This
right of first refusal shall be inapplicable to a lease to any party affiliated
with Landlord.  ALL OTHER TERMS AND CONDITIONS OF THE
AGREEMENT REMAIN UNCHANGED.  LANDLORD:EXXON RESEARCH AND ENGINEERING COMPANYBy:
  /s/ M. E. AdamsLeasing ManagerDate:
  September 26, 1994TENANT:MEDAREX, INC.By:
  /s/ Michael AppelbaumDate:
  September 23, 1994


LEASE AMENDMENT NO. 3  LEASE AMENDMENT made as of this 27th day of
October, 1994 to that certain Lease Agreement dated as of May 6, 1993
(Agreement) between EXXON RESEARCH AND ENGINEERING COMPANY (Landlord) and
MEDAREX, INC. (Tenant).  WHEREAS the parties recently entered into
Lease Amendment No. 2 whereby effective October 1, 1994 Tenant has
leased additional space from Landlord designated as CC323-397, and  WHEREAS the parties omitted to address in
said Lease Amendment No. 2 certain effects for Medarex if all or a portion
of CC-3 is leased to a third party;  NOW, THEREFORE, the parties agree that
effective immediately the Agreement is amended as follows:  1.If
(i) Lease Amendment No. 2 is terminated in accordance with Paragraph
8 thereof and Landlord leases CC-3 to a third party, or (ii) Landlord
leases to a third party substantially all of the remainder of CC-3 not leased
to Tenant, and in either case (i) or (ii) Tenant has made payments to
Landlord for Tenants share (not to exceed $20,000) of Landlords reasonable
costs and expenses to enclose the atrium in glass pursuant to Paragraph 5 of
Lease Amendment No. 2, then Landlord shall credit toward Tenants next
succeeding rent payment an amount equivalent to such payments made by Tenant.  ALL OTHER TERMS AND CONDITIONS OF THE
AGREEMENT REMAIN UNCHANGED.  LANDLORD:  EXXON RESEARCH AND ENGINEERING COMPANYBy:
  /s/ M.E. AdamsLeasing ManagerDate:
  October 27, 1994TENANT:MEDAREX, INC.By
  /s/ Michael AppelbaumSr. Vice PresidentDated:
  October 31, 1994


LEASE AMENDMENT NO. 4  LEASE
AMENDMENT made as of this 16th day of October 1995 to that certain Lease
Agreement dated as of May 6, 1993 (Agreement) between EXXON RESEARCH AND
ENGINEERING COMPANY (Landlord) and MEDAREX, INC. (Tenant),  WHEREAS, the
parties desire to amend the Agreement to add additional indoor reserved parking
spaces to the Demised Premises:  NOW THEREFORE, the parties agree that the
Agreement is hereby amended as follows:  1. The Tenants entitlement to indoor parking spaces as
defined in Section 42.01of the Agreement and Lease
Amendment No. 1, at paragraph 1 and Lease Amendment No. 2 at
paragraph 7, are increased effective November 1, 1995 by the addition of
five (5) indoor parking
spaces. This addition of five (5) spaces
shall increase the Tenants entitlement to indoor parking spaces to ten (10) under
this Lease Amendment No. 4.  2. Additional Rent for the five (5) additional
indoor parking spaces made part of Tenants entitlement through this Lease
Amendment No. 4 shall be Four Thousand Eight Hundred dollars ($4,800.00)
annually. (For information purposes only, Additional Rent for the five (5) spaces
is calculated on a. monthly rate of Eighty dollars ($80.00) per space.  3. Landlord may terminate this Lease
Amendment No, 4 at anytime on not less than sixty (60)
days written notice to Tenant, in which event Tenant shall cease utilizing and
surrender the five (5) spaces
identified in paragraph 1 above.  ALL OTHER
TERMS AND CONDITIONS OF THE AGREEMENT REMAIN UNCHANGED.  LANDLORD:EXXON RESEARCH AND ENGINEERING COMPANYBy:
  /s/ M.E. AdamsLeasing ManagerDate:
  October 16, 1995TENANT:MEDAREX, INC.By:
  /s/ Lisa DrakemanDate:
  October 16, 1995


LEASEAMENDMENTNO. 5  LEASE AMENDMENT made as of this 31ST day of January, 1997 to that certain Lease
Agreement dated as of May 6, 1993, and as amended, (Agreement) between
EXXON RESEARCH AND ENGINEERING COMPANY (Landlord) and MEDAREX, INC.
(Tenant).  WHEREAS, the parties desire to amend the
Agreement to add additional space to the Demised Premises;  NOW, THEREFORE, the parties agree that the
Agreement is hereby amended as follows:  1. The Demised Premises as defined in Section 1.01(d) of
the Agreement are enlarged effective February 3, 1997 by the addition of
those portions of the Building hereby leased to Tenant commonly known as:  ·The
northern interior sector of Pilot Wing PF East to include PF100B, PF101, PF103,
PF107, PF110B, PF111, PF113, PF117, PF120B and PF121, being more particularly
depicted on LA5-Exhibit A attached hereto, together with the proportionate
share of (i) the mechanical room depicted as PF105, (ii) the corridor
which separates PF East and PF West, and (iii) the mechanical space on
Level M of the PF Wing, together deemed to be 4,556 rentable square feet
(PF-NE (inside)).  ·The
northern exterior sector of Pilot Wing PF East contiguous to the interior
sector defined above, deemed to be 1,991 rentable square feet (PF-NE
(outside)), being more particularly described on LA5-Exhibit A attached
hereto,  ·The
zero level identified as laboratory L0001 depicted on LA5-Exhibit B
attached hereto and deemed to be 1,397 rentable square feet; and  ·The
3rd floor office identified as CC348 depicted on LAS-Exhibit C attached
hereto and deemed to be 159 rentable square feet.  2.Tenant acknowledges that it has thoroughly
examined PF-NE (inside), PF-NE (outside), L00l, and CC348 and takes said space
in AS IS condition as of February 1, 1997.  3.That portion of the Demised Premises referred to
as CC323-397 (depicted on LA5-Exhibit C) in Lease Amendment 2 is
understood to consist of 7,638 rentable square feet rather than 7,368 rentable
square feet as mistakenly identified in Lease Amendment 2.


4.Rent  A.Rent for PF-NE (inside)
for the demised term (Rent shall be paid from February 17, 1997 to and
including September 30, 1998) shall be One Hundred Eighty Thousand Seven
Hundred Thirty-five and 90/100 Dollars ($180,735.90), payable in equal monthly
installments of Nine Thousand Thirty-six and 80/100 Dollars ($9,036.80) which
sum shall be the Basic Monthly Rent. (For information purposes only, Basic Rent
for PF-NE (inside) is calculated on a unit rate of $24.50 per rentable square
foot (hereinafter, PRSF) per year.)  B.Rent
for PF-NE (outside) for the demised term (Rent shall be paid from February 17,
1997 to and including September 30, 1998) shall be Seventeen Thousand
Seven Hundred Thirty and 81/100 Dollars ($17,730.81), payable in equal monthly
installments of Eight Hundred Eighty-six and 54/100 Dollars ($886.54) which sum
shall be the Basic Monthly Rent. (For information purposes only, Basic Rent for
PF-NTE (outside) is calculated on a unit rate of $5.50 (adjusted operating
expenses) PRSF per year.)  C.Rent
for L00l for the demised term (Rent shall be paid from February 17, 1997
to and including September 30, 1998) shall be Twenty-Seven Thousand One
Hundred Forty-three and 90/100 Dollars ($27,143.90), payable in equal monthly
installments of One Thousand Three Hundred Fifty-seven and 20/100 Dollars
($1,357.20) which sum shall be the Basic Monthly Rent. (For information
purposes only, Basic Rent for L00l is calculated on a unit rate of $12.00 PRSF
per year.)  D.Rent
for CC348 for the demised term (Rent shall be paid from February 17, 1997
to and including September 30, 1998) shall be Five Thousand Six Hundred
Sixty-three and 88/100 Dollars ($5,663.88), payable in equal monthly
installments of Two Hundred Eighty-three and 19/100 Dollars ($283.19), which
sum shall be the Basic Monthly Rent. (For information purposes only, Basic Rent
for CC348 is calculated on a unit rate of $22.00 PRSF per year.)  E.Rent
for CC323-397 for the demised term (Rent shall be paid from February 17,
1997 to and including September 30, 1998) shall be Two Hundred Seventy-two
Thousand Eighty and 21/100 Dollars ($272,080.21), payable in equal monthly
installments of Thirteen Thousand Six Hundred Four and 01/100 Dollars
($13,604.01), which sum shall be the Basic Monthly Rent. (For information
purposes only, Basic Rent for CC323-397 is calculated on a unit rate of $22.00
PRSF per year.)  5.Additional Rent. The
following shall be added to Article 6, Section 6.01 beginning as the
third paragraph therein:  Tenant shall pay as Additional Rent for each
calendar year or proportionate part thereof during the lease term an amount
equal to Tenants proportionate share, to wit,


now five and fifty-nine hundredths percent (5.59%),of the
amount of Operating Expenses for such calendar year (Tenants Operating
Payment). Tenants Operating Payment shall also include charges for PFNE
(outside) in six categories, which charges shall be calculated as percentages
of the like effective charges per square foot (in each case, subject to
exclusions from Operating Expenses as described above) for the balance of the
Demised Premises, as follows: site security, 100%; grounds maintenance,
facilities maintenance and repair, site operations. management, and insurance
(including, as the case may be, payments in lieu thereof, or imputed premiums
pursuant to Article 11 of the Lease), each 50%. Said Operating Expenses
shall be more fully described in LA5-Exhibit M, attached, which shall
replace Exhibit M from Lease Amendment No. 1.  6. Real Estate Taxes. The Tenants percentage
share of Taxes as defined in Article 6, Section 6.02 of the Lease shall
be increased from four and eighty-two hundredths percent (4.82%) to five and
eighty-five hundredths percent (5.85%) under this Lease Amendment No. 5.  7. Section 6.05 Utility Charges is
amended by the following:  ·deleting
the first sentence of the second paragraph therein and replacing it with the
following sentence: Tenants adjusted utility charge for the year 1997 shall
include the addition of the PF-NE (inside) (See LA5-Exhibit D, attached)
and L00l (See LA5-Exhibit E, attached) utilities to the 1994 utility base
year.; and  ·deleting
January 1, 1995 and substituting it with February 1, 1997.  8. Lease Exhibit F-4 shall be deleted
and replaced with LA5-Exhibit-F4, attached.  9. Tenants entitlement to indoor parking
spaces remains at five (5) spaces. Tenants additional annually leased
indoor parking spaces shall be increased from five (5) spaces by one (1) space
making a total of six (6) additionally leased indoor spaces under this
Lease Amendment No. 5. Each additionally leased indoor space shall cost
Nine Hundred sixty and 00/100 Dollars ($960.00), annually.  10. Landlord may terminate this Lease
Amendment No. 5 or any portion thereof at any time on not less than sixty
(60) days written notice to Tenant, in which event Tenant shall quit and
surrender PP-NE (inside), PP-NE (outside), L00l and/or CC348 to Landlord, broom
clean, in good safe order and condition, ordinary wear and tear excepted, and
Tenant shall remove all of its property therefrom.  11. If Landlord receives a bona tide offer
from a third party to lease more space in CC-3 than is being leased by Tenant
hereunder, which offer Landlord desires to accept, Landlord shall deliver a
copy of such offer to Tenant, and Tenant may, within twenty (20) business days
thereafter, elect to lease the subject space on the same terms as those set
forth in the offer. If Tenant does not accept such offer, Tenants rights under
this


Paragraph 11 shall be extinguished, and Landlord may notify Tenant of
termination under this Lease Amendment No. 5.  As respects that portion of the Demised
Premises known as CC323-397 and lease the subject space to such third
party.  This right of first refusal shall
be inapplicable to a lease to any party affiliated with Landlord.  ALL OTHER TERMS AND CONDITIONS OF THE AGREEMENT REMAIN UNCHANGED.  LANDLORD: EXXON RESEARCH
AND ENGINEERING COMPANY  By:
  /s/ Alfredo LopezDate:
  January 31, 1997TENANT:MEDAREX, INC.By:
  /s/ Michael AppelbaumDate
  January 31,1997


LEASE AMENDMENT NO.6  LEASE AMENDMENT made as of this 22ndday of May, 1997 to that certain
Lease Agreement dated as of May 6, 1993, and as amended, (Agreement)
between EXXON RESEARCH AND ENGINEERING COMPANY (Landlord) and MEDAREX, INC.
(Tenant).  WHEREAS, the parties desire to amend the
Agreement to add additional space to the Demised Premises;  NOW, THEREFORE, the parties agree that the
Agreement is hereby amended by enlarging the Demised Premises as defined in Section 1.01(d) of
the Agreement, effective June 2, 1997, by the addition of that space
identified as CC-350, deemed to be 159 rentable square feet, being more
particularly depicted on LA6-Exhibit A.  Tenant acknowledges that it has thoroughly
examined CC-3 50 and takes said space in AS IS condition as of June 2,
1997.  Rent  Rent for CC-350 for the demised term (Rent
shall be paid from June 2, 1997 to and including September 30, 1998)
shall be Three Thousand Four Hundred Ninety-Eight and 00/100 Dollars
($3,498.00), payable in equal monthly installments of Two Hundred Ninety-One
and 10/100 Dollars ($291.10) which sum shall be the Basic Monthly Rent. (For
information purposes only, Basic Rent for CC-350 is calculated on a unit rate
of $22.00 per rentable square foot (hereinafter, PRSF) per year.)  Landlord may terminate this Lease Amendment No. 6
or any portion thereof, at any time on not less than sixty (60) days written
notice to Tenant, in which event Tenant shall quit and surrender CC-350 to
Landlord, broom clean, in good safe order and condition, ordinary wear and tear
excepted, and Tenant shall remove all of its property therefrom.  If Landlord receives a bona fide offer from a
third party to lease more space in CC-3 than is being leased by Tenant
hereunder, which offer Landlord desires to accept, Landlord shall deliver a
copy of such offer to Tenant, and Tenant may, within twenty (20) business days
thereafter, elect to lease the subject space on the same terms as those set
forth in the offer. If Tenant does not accept such offer, Tenants rights under
this Amendment No. 6 shall be extinguished, and Landlord may notify Tenant
of termination under this Lease Amendment No. 6 as respects that portion
of the demised premises known as CC-350 and lease the subject space to such
third party. This right of first refusal shall be inapplicable to a lease to
any party affiliated with Landlord.


ALL OTHER TERMS AND CONDITIONS OF THE
AGREEMENT REMAIN UNCHANGED.  :
  LANDLORD:EXXON RESEARCH AND ENGINEERING COMPANYBy:
  /s/ M.E. AdamsDate:
  May 22, 1997:
  TENANTMEDAREX, INC.By:
  /s/ Michael AppelbaumDate:
  May 22 1997


LEASE AMENDMENT NO.7 and LEASE RENEWAL  LEASE AMENDMENT and LEASE RENEWAL made as of this 10th day of October,1997 to that certain lease
agreement dated as of May 6, 1993, and as amended, (Agreement) between
EXXON RESEARCH AND ENGINEERING COMPANY (Landlord) and MEDAREX, INC.
(Tenant).  WHEREAS, the parties desire to amend the
Agreement to add additional space to the Demised Premises; and  WFIEREAS, the parties desire to renew the Agreement for one (1) five
(5) year renewal period extending from October 1, 1998 through September 30,
2003;  NOW, THEREFORE, the parties agree that the Agreement is hereby amended
by enlarging the Demised Premises by the addition of the space identified as
CC356, deemed to be 296 rentable square feet, CC3S6A, deemed to be 222 rentable
square feet, CC362, deemed to be 222 rentable square feet, CC318, deemed to be
222 rentable square feet, CC320, deemed to be 159 rentable square feet, and
CC322, deemed to be 222 rentable square feet (in the aggregate being deemed to
be an additional 1,343 rentable square feet), being more particularly depicted
on LA7 -Exhibit A.  Tenant acknowledges that it has thoroughly examined CC356, CC356A, CC362,
CC318, CC320, and CC322 and takes said space in AS IS condition as of November 1,
1997.  Rent for CC356, CC356A, CC362, CC318, CC320, and CC322 for the demised
term (Rent shall be paid from November 1, 1997 to and including September 30,
1998) shall be Twenty-Seven Thousand Eighty-Three and 83/100 dollars
($27,083.83), payable in equal monthly installments of Two Thousand Four
Hundred Sixty-Two and 17/100 dollars ($2,462.17) which sum shall be the Basic
Monthly Rent. (For information purposes only, Basic Rent for CC356, CC356A,
CC362, CC318, CC320, and CC322 is calculated on a unit rate of $22.00 per
rentable square foot per year.)  Landlord may terminate this Lease Amendment No. 7 or any portion
thereof at any time on not less than sixty (60) days written notice to Tenant,
in which event Tenant shall quit and surrender said space to Landlord, broom
clean, in good safe order and condition, ordinary wear and tear excepted, and
Tenant shall remove all of its property therefrom.  NOW, THEREFORE, the parties agree that the Agreement is hereby renewed
as follows:  1.Demised
Premises  The Demised
Premises as defined in Section 1.01(d) of the Agreement consist of
those portions of the Building currently leased to Tenant and commonly


identified (with associated square footage) as:   
  LF/LH-l
  37,200 SF
  CC-3
  9,299 SF(CC318, CC320, CC322, CC323, CC324,CC327, CC328, CC329, CC330, CC330A,CC334, CC334A, CC333, CC335, CC338,CC338A, CC339, CC341, CC342, CC342A,CC343, CC344, CC346, CC348, CC350,CC356, CC356A, CC362, CC396, CC397)
  L00l
  1,397 SF
  PF-NE (inside)
  4,556SF
  PF-NE (outside)
  1,991 SF
 2.Rent  A. Rent for
LF/LH-l for the demised term (Rent shall be paid from October 1, 1998 to
and including September 30, 2003) shall be Five Million One Hundred
Fifteen Thousand and 00/100 Dollars ($5,115,000.00), payable in equal monthly
installments of Eighty-Five Thousand Two Hundred Fifty and 00/100 Dollars
($85,250.00) which sum shall be the Basic Monthly Rent. (For information
purposes only, Basic Rent for LF/LH- 1 is calculated on a unit rate of $27.50
per rentable net square foot per year.)  B. Rent for
CC-3 for the demised term (Rent shall be paid from October 1, 1998 to and
including September 30, 2003) shall be One Million Twenty-Two Thousand and
Eight Hundred Ninety and 00/100 Dollars ($1,022,890.00), payable in equal
monthly installments of Seventeen Thousand Forty-Eight and 17/100 Dollars
($17,048.17) which sum shall be the Basic Monthly Rent. (For information
purposes only, Basic Rent for CC-3 is calculated on a unit rate of $22.00 gross
plus energy per square foot per year.)  C. Rent for
L00l for the demised term (Rent shall be paid from October 1, 1998 to and
including September 30, 2003) shall be Eighty-Three Thousand Eight Hundred
Twenty and 00/100 Dollars ($83,820.00), payable in equal monthly installments
of One Thousand Three Hundred Ninety-Seven and 00/100 Dollars ($1,397.00) which
sum shall be the Basic Monthly Rent. (For information purposes only, Basic Rent
for L00l is calculated on a unit rate of $12.00 per rentable net square foot
per year.)  D. Rent for
PF/NE (inside) for the demised term (Rent shall be paid from October 1,
1998 to and including September 30, 2003) shall be Five Hundred
Fifty-Eight Thousand One Hundred Ten and 00/100 Dollars ($558,110.00) payable
in equal monthly installments of Nine Thousand Three Hundred One and 83/100
Dollars ($9,301.83) which sum shall be the Basic Monthly Rent. (For information
purposes only, Basic Rent for PF/NE (inside) is calculated on a unit rate of
$24.50 per rentable net square foot per year.)


E. Rent for
PF/NE (outside) for the demised term (Rent shall be paid from October 1,
1998 to and including September 30, 2003) shall be Fifty-Four Thousand
Seven Hundred Fifty-Two and 50/100 Dollars ($54,752.50) payable in equal
monthly installments of Nine Hundred Twelve and 54/100 Dollars ($912.54) which
sum shall be the Basic Monthly Rent. 
(For information purposes only, Basic Rent for PF/NE (outside) is calculated
on a unit rate of $5.50 per rentable net square foot per year.)  3.Renewal
Option  Article 41,
Section 41.01 shall be deleted and replaced with:  Provided that
Tenant is not in default under any of the terms and conditions of this
Agreement beyond the periods for notice and cure pursuant to Article 21
hereof, Tenant shall have the option to renew this Agreement for one additional
term of five (5) years,
upon the same terms and conditions contained in this Agreement, except (i) there
shall be one (1) five (5) year renewal option, and (ii) the Base
Rent shall be recalculated using the same Index as identified in Section 6.03
above. The renewal rent for each year of the renewal term shall be the
equivalent of $27.50 per square foot of net rentable space for LF/LH-1, $22.00
gross plus energy per square foot for CC-3 which includes CC318, CC320, CC322,
CC323, CC324, CC327, CC328, CC329, CC330, CC330A, CC334, CC334A, CC333, CC335,
CC338, CC338A, CC339, CC341, CC342, CC342A, CC343, CC344, CC346, CC348, CC350,
CC356, CC3S6A, CC362, CC396, CC397, $12.00 per rentable net square foot for
L00l, $24.50 per rentable net square foot for PF/NE (inside), and $5.50 per
rentable net square foot for PF/NE (outside), all adjusted upward (or downward
as the case may be) by the percentage change in the Index from October 1,
1998 to the commencement date of the renewal term.  If the renewal
option is exercised by Tenant, the renewal term shall commence on October 1,
2003 and expire on September 30, 2008. In order to exercise the renewal
option, Tenant must give Landlord notice of its intention to renew at least
fourteen (14) months prior to the expiration date of the initial term. Time
shall be of the essence with respect to the exercise of the renewal option.  4.Office
Area -CC-3  Tenant will
continue to occupy CC-3 under the terms of the Agreement. In the event Landlord
receives a third party proposal for the rental of CC-3 and Tenant does not
exercise its right to lease the balance of the third floor of the Central
Functions Wing, per the terms and conditions of the Agreement, if Landlord
chooses to accept the third party proposal for the rental of CC-3 Tenant has
the option to relocate to the 3,983 square foot CF-Stack level. The rental rate
for the CF-Stack level will be $12.00 gross plus energy per rentable square
foot on an as is basis. Landlord will contribute up to $25.00 (total) per
rental square foot for Tenant improvements. The cost for such improvements will
be amortized above the base rent over the term of the renewal at an interest
rate of 10%.


5.Right
of First Refusal  Subject to any
and all other tenants pre-existing rights, Tenant shall be granted a right of
first refusal on the CF-Stack area measuring 3,983 rentable square feet. Such
right will terminate upon the earlier of (a) the Tenant leasing the entire
Central Functions Wing, or (b) the termination of Tenants occupancy of
the CC-3 area.  ALL OTHER TERMS AND CONDITIONS of the
Agreement remain unchanged.  LANDLORD:EXXON RESEARCH AND ENGINEERING COMPANYBy:
  /s/ Alfredo LopezDate:
  October 15, 1997TENANT:MEDAREX, INC.By:
  /s/ Donald DrakemanDate:
  October 10, 1997


LEASE AMENDMENT NO.8  LEASE AMENDMENT made as of this 20th day of January, 1999 to that certain Lease
Agreement dated as of May 6, 1993, and as amended, and renewed on October 10,
1997 extending from October 1, 1998 through September 30, 2003
(Agreement) between EXXON RESEARCH AND ENGINEERING COMPANY (Landlord) and
MEDAREX, INC. (Tenant).  WHEREAS, the parties desire to amend the
Agreement to add additional space to the Demised Premises;  NOW, THEREFORE, the parties agree that the
Agreement is hereby amended as follows:  1.The Demised Premises as
defined in Section 1.01(d) of the Agreement are enlarged effective February 1,
1999 by the addition of those portions of the Building hereby leased to Tenant
commonly known as:  ·That section
of the PC corridor of Level 1 opposite the entrance to Pilot Wing PF East
identified as PC 121 and PC 123, being more particularly depicted on LA8-Exhibit A
attached hereto and deemed to be 318 rentable square feet.  ·The 3rd floor
offices identified as CC-310, CC-312, and CC-314 depicted on LA5-Exhibit C
attached hereto and deemed to be 714 rentable square feet.  2.Tenant acknowledges
that it has thoroughly examined PC121, PC123, CC-310, CC312, and CC-314 and
takes said space in AS IS condition as of February 1, 1999.  3.Rent  A.Rent
for PC12l and PC123 for the demised term (Rent shall be paid from February 1,
1999 to and. including September 30, 2003) shall be Twenty-Eight Thousand
One Hundred Ninety-Six and 00/100 Dollars ($28,196.00), payable in equal
monthly installments of Five Hundred Three and 50/100 Dollars ($503.50)which sum shall be the Basic Monthly Rent. (For information
purposes only, Basic Rent for PC121 and PC123 is calculated on a rate of $19.00
per rentable square foot (hereinafter, PRSF) per year.)  B.Rent
for CC-310, CC-312, and CC-314 for the demised term (Rent shall be paid from February 1,
1999 to and including September 30, 2003) shall be Seventy-Three Thousand
Three Hundred Four and 00/1 00 Dollars ($73,304.00), payable in equal monthly
installments of One Thousand Three Hundred Nine and 00/100 Dollars ($1,309.00)
which sum shall be the Basic Monthly Rent. (For information purposes only,
Basic Rent for CC-310, CC-312, and CC-314 is calculated on a unit rate of
$22.00 PRSF per year.)


4.Additional Rent  Tenant shall pay as Additional Rent for PC121
and PC123 for each calendar year or proportionate part thereof during the lease
term an amount equal to Tenants proportionate share, to wit, now five and
sixty-three hundredths percent (5.63%),of the amount of Operating
Expenses for such calendar year (Tenants Operating Payment).  5.Real Estate Taxes. The
Tenants percentage share of Taxes as defined in Article 6, Section 6.02
of the Lease shall be increased from five and eighty-five hundredths percent (5.85%)to
five and eighty-nine hundredths percent (5.89%)under this Lease Amendment No. 8.  6.Landlord may terminate
the second portion of Provision 1 of this Lease Amendment No. 8, at any
time on not less than sixty (60) days written notice to Tenant, in which event
Tenant shall quit and surrender CC-310, CC-312, and CC-314, or any combination
of said space based on Landlords written notice, to Landlord, broom clean, in
good safe order and condition, ordinary wear and tear excepted, and Tenant
shall remove all of its property therefrom.  7.If Landlord receives a
bona fide offer from a third party to lease more space in CC-3 than is being
leased by Tenant hereunder, which offer Landlord desires to accept, Landlord
shall deliver a copy of such offer to Tenant, and Tenant may, within twenty
(20) business days thereafter, elect to lease the subject space on the same
terms as those set forth in the offer. If Tenant does not accept such offer,
Tenants rights under this Paragraph 7 shall be extinguished, and Landlord may
notify Tenant of termination under this Lease Amendment No. 8 as respects
that portion of the demised premises known as CC-310, CC-312 and CC-314 and
lease the subject space to such third party. This right of first refusal shall
be inapplicable to a lease to any party affiliated with Landlord.  ALL OTHER TERMS AND CONDITIONS OF THE
AGREEMENT REMAIN UNCHANGED.  LANDLORD:EXXON RESEARCH AND ENGINEERING COMPANYBy:
  /s/ Alfredo LopezDate:
  January 20, 1999TENANT:MEDAREX, INC.By:
  /s/ Michael AppelbaumDate:
  January 20, 1999


LEASE AMENDMENT No. 9  LEASE AMENDMENT made as of this
     day of June, 1999 to that certain Lease Agreement
dated as of May 6, 1993, and as amended and renewed on October 10,
1997 extending from October 1, 1998 through September 30, 2003
(Agreement) between EXXON RESEARCH AND ENGINEERING COMPANY (Landlord) and
MEDAREX, INC. (Tenant).  WHEREAS, the parties desire to amend the
Agreement by redefining (although not modifying the absolute number of)
rentable square feet:  NOW, THEREFORE, the parties agree that the
Agreement is hereby amended as follows:  1.The Demised
Premises as defined in Section 1.01(d) of the Agreement are modified
as follows, and as more particularly depicted on LA9 - Exhibit C,
attached:  ·CC-310 will
be reduced to 79 rentable square feet (a reduction of 159 rentable square
feet),  ·CC-311 will
be added to the third floor offices within the Demised Premises, such space
consisting of 159 rentable square feet. (For informational purposes only it
should be noted that rent and any other money owed by Tenant to Landlord under
the Agreement remains unchanged because of the rentable square foot equivalency
of the modifications.)  2.Landlord
hereby permits Tenant, at no additional cost to Tenant, to utilize the CC
kitchen area identified as CC-313, being more particularly depicted on LA9 -Exhibit C.  3.Tenant
acknowledges that it has thoroughly examined CC-311 and takes its space in AS
IS condition as of the effective date of this Amendment No. 9.  4.Landlord may
terminate provisions 1 and 3 of this Lease Amendment No. 9 at any time on
not less than sixty (60) days written notice to Tenant, in which event Tenant
shall quit and surrender CC-310, CC-311, and its use of CC-3 13, or any
combination ofsaid space based on Landlords
written notice to Landlord, broom clean, in good safe order and condition,
ordinary wear and tear accepted, and Tenant shall remove all of its property
therefrom.  5.If Landlord
receives a bona fide offer from a third party to lease more space in CC-3 than
is being leased by Tenant hereunder, which offer Landlord desires to accept,
Landlord shall deliver a copy of said offer to Tenant and Tenant may, within
twenty (20) business days thereafter, elect to lease the subject space on the
same terms as those set forth in the offer. If Tenant does not accept such
offer, Tenants rights under this Paragraph 5shall be
extinguished, and Landlord may notify Tenant of termination under this Lease
Amendment No. 9 as respects that portion of the Demised Premises known as


CC-310, CC-311, and CC-313 and lease the
subject space to such third party. This right of first refusal shall be
inapplicable to a lease to any party affiliated with Landlord.  ALL OTHER TERMS AND CONDITIONS OF THIS
AGREEMENT REMAIN UNCHANGED.  LANDLORD:EXXON RESEARCH AND ENGINEERING COMPANYBy:
  /s/ M.E. AdamsDate:
  June 9, 1999TENANT:MEDAREX, INC.By:
  /s/ Michael AppelbaumDate:
  June 17, 1999


Lease
Amendment No. 10 Notice to
Vacate CC-3 Leasehold  August 26, 1999  Dear Dr. Drakeman:  Pursuant to that certain Lease Agreement
dated as of May 6, 1993, and as amended, (Agreement) between Exxon
Research and Engineering Company (Landlord) and Medarex, Inc.
(Tenant), Landlord is exercising its right to terminate the lease agreement
with respect to all space identified as CC-3 space. This letter serves as the
60 day written notice to Tenant advising you that you shall quit and surrender
the following space by November 15, 1999, leaving it broom clean, in good
safe order and condition, ordinary wear and tear excepted, and with all of
tenants property removed therefrom:  CC-3, which consists
of:  CC-310, CC-311, CC-312, (use of CC-313),
CC-314, CC-318, CC-320, CC-322, CC-323, CC-324, CC-327, CC-328,CC-329,
CC-330, CC-330A, CC-333, CC-334, CC-334A, CC-335, CC-338, CC-338A, CC-339,
CC-341, CC-342, CC-342A, CC-343, CC-344, CC-346, CC~348, CC-350, CC-356.
CC-356A, CC-362, CC-396, and CC-397  From November 15, 1999 through the
expiration of the Agreement (September 30, 2003) the Demised Premises as
defined in Section 1.01(d) of the Agreement shall consist of LF/LH-1,
L001, PC-121, PC-123, PF/NE (inside), PF(NE (outside). Additionally, Section 42.01
of the Agreement shall be amended by the substitution of two (2), only, indoor
parking spaces rather than any other number of indoor parking space
entitlements to which the parties had agreed previously.  Rent for the
balance of the Demised Premises from November 15, 1999 to the expiration
of the Agreement shall be unimpacted by this surrender of the CC-3 spaces.  ALL OTHER
TERMS AND CONDITIONS OF THE AGREEMENT REMAIN UNCHANGED.  Please return
one (1) fully executed original copy to me.  Very truly yours,  EXXON RESEARCH AND ENGINEERING


COMPANYBy:
  /s/ Michael E. Adams
  RECEIVED AND AGREED TO BY MEDAREX, INCORPORATED  By:
  /s/ Michael AppelbaumDate:
  9/18/99


LEASE AMENDMENT NO. 11  LEASE AMENDMENT made as of this 10th day of November, 1999 to that
certain Lease Agreement dated as of May 6. 1993 and as amended thereafter,
and renewed on October 10, 1997 and as amended thereafter between Exxon
Research and Engineering Company (Landlord) and MEDAREX. INC. (Tenant),
(Lease Agreement).  WHEREAS, Tenant wishes to relinquish its six (6) additionally
leased indoor parking spaces added to the Demised Premises under Lease
Amendments Nos. 4 & 5;  WHEREAS, Landlord is willing to allow Tenant to relinquish said
additionally leased indoor parking spaces;  WHEREAS, Tenant wishes Landlord to manage the installation and
operation of a temporary emergency generator and to lease additional space
short term from Landlord for this purpose; and  WHEREAS, Landlord is willing to provide this service and make such
additional space available for lease to Tenant on the same terms and conditions
as are set forth in the Lease Agreement, subject only to the modifications set
forth below:  NOW, THEREFORE, the parties agree to the following:  (1) The parties agree that as of December 1, 1999, Tenant
shall relinquish and Landlord shall permit the relinquishment of the six (6) additionally
leased indoor parking spaces previously leased by Tenant at the annual cost of
Nine Hundred Sixty and 00/100 Dollars ($960.00) per space. The parties agree
that Landlord shall reimburse Tenant the one month, pre-paid, prorated amount
of Four Hundred Eighty and 00/100 Dollars ($480.00) for the December 1999
payment of said six (6) indoor spaces.  (2) The Demised Premises as defined in Section 2.01 of the
Lease Agreement are enlarged for the period of three (3) months effective December 1,
1999, lasting until March 1, 2000 by the addition of the area designated
as the South East Exterior of the PF Pilot Wing, adjacent to the Liquid
Nitrogen Platform which additional space is deemed to be 762 rentable square
feet, being more particularly described on LA11-Exhibit A attached hereto.
(hereinafter Temporary Emergency Generator Pad).  (3) The Temporary Emergency Generator Pad shall be leased without
increasing the Rent paid (which, for informational purposes only, currently is
Ninety Seven Thousand Three Hundred Sixty-Four and 88/100 Dollars
(597,364.88)).  (4) Landlord disclaims any warranties of any kind, expressed or
implied, associated with the installation and/or operation of the emergency
generator which will be installed on the Temporary Emergency Generator Pad.


ALL OTHER TERMS AND CONDITIONS OF THE LEASE AGREEMENT REMAIN THE SAME.   TENANT:MEDAREX,
  INC.By:
  /s/ Michael AppelbaumDate:
  11/10/99LANDLORD:E XXON
  RESEARCH AND ENGINEERING COMPANYBy:
  /s/ Alfredo LopezDate:
  11/29/08


AMENDMENT No.12 and LEASE RENEWAL  LEASE
AMENDMENT and LEASE RENEWAL (Lease Amendment) made as of this 30th day of September, 2003, to that certain Lease
Agreement dated as of May 6, 1993 between Exxon Research and Engineering Company (nowknown
as ExxonMobil Research and Engineering
Company)(Landlord), and Medarex, Inc.(Tenant) as amended (Lease Agreement).  WHEREAS, the
parties agree that certain provisions of the Lease Agreement, as identified
below, should be amended;  WHEREAS, the
parties desire to renew the Lease Agreement as herein amended for one (1) five
year renewal period extending from October 1,2003 through September 30,
2008 (the Second and Final Five (5) Year
Term); and  NOW,
THEREFORE, the parties agree that the Lease Agreement is hereby amended and
renewed as follows:  1.Demised Premises  The Demised Premises as defined in Section 1.01(d) of
theLease Agreement consists of those portions of the Building currently leased to Tenant and
commonly identified (with associated Rentable Square Footage) as:  A.
  
  LF/LH-1 (as
  defined in Lease Amendment No. 7)
  
  37,200 RSFB.
  
  L00l (as
  defined in Lease Amendment No. 7)
  
  1.397 RSFC.
  
  PC121 &
  PC123 (as defined in Lease Amendment No. 8)
  
  318 RSFD.
  
  PFINE
  (inside) (as defined in Lease Amendment No. 7)
  
  4,556 RSFE.
  
  PF/NE
  (outside) (as defined in Lease Amendment No. 7)
  
  1,991 RSFTOTAL
  
  45,462 RSF  2.Renewal Option
Base
Rent Recalculation  Base Rent for this Second and Final Five (5)Year Term shall be calculated in accordance with
the following approach. That portion of the last sentence of the first
paragraph of Item 3. Renewal Option of Lease Amendment #7 (with
reference to Article 41, Section 41.01 of the Lease), which reads:  all adjusted upward (or downward as the case may be) by the percentage change in the
Index (CPI-U Index) from October 1, 1998 to the commencement date of the
renewal term, SHALL BE DELETED AND REPLACED WITH:  -all adjusted upward (or downward as the case may be) by the
percentage change in the Index (CPI-U Index) from the October 1998 Index
(170.3) to the August 2003 Index (191.1), which is an upward adjustment of
12.21%.


3.Base Rent
Recalculation Modification and Additional Adjustment  The calculation specified in Item 2, above,
may be modified on or about mid-November 2003, when the October 2003
Index is published, and to reflect the October 2003 Index. If the October 2003
Index has changed, when compared with the previously referenced August 2003
Index, then the Rent specified in Item 4, below, shall be modified and adjusted
by that percentage change in the Index, using the Rent recalculation method
specified in Item 2, above. This potential additional adjustment in Rent, if
required, shall be documented in a separate subsequent Lease Amendment. If an
adjustment in Rent is required, as stated above, the overall final recalculated
Rent shall be reflected in the first quarter 2004 Invoice (dated on or about February 2,
2004). In addition, if required, the adjustment as it impacts the fourth
quarter 2003 Rent previously charged in the fourth quarter 2003 invoice, shall
also be reflected in the first quarter 2004 invoice, and shall be described as
Base Rent Adjustment, 4Q 2003. In the
event that this Rent adjustment is not required (suchthat there is no change in the CPI-U from August 2003
to October 2003), then Landlord will give Notice to Tenant that no further
adjustment is required, and that a subsequent Lease Amendment to cover this
contingency will not be forthcoming.  4.Rent  The total Rent payment (as calculated using
the change in indexes from October 1998 to August 2003, as specified
in Item 2, above) for the Demised Premises for the Second and Final Five (5) Year Term shall be
Six-Million Five-Hundred Fifty-Five Thousand One-Hundred Eighty and 00/100
Dollars ($6,555,180.00)payable in equal quarterly
installments of Three-Hundred Twenty-Seven Thousand Seven-Hundred Fifty-Nine
and 00/100 Dollars ($327,759.00) as explained in further detail below, in Items
4-A, B, C, D and F. The quarterly invoices are dated and released on or about
the first work day of February, May, August, and November per annum. Each
quarterly invoice encompasses the charges for Rent and Additional Rent for a
calendar quarter, where for example, the February 2, 2004 invoice (the
1Q-2004 Invoice) will cover these charges for January, February, and March 2004.
Each quarterly invoice also encompasses Optional Services  Usage charges
reported for the previous three (3) months. The 4Q-2003 Invoice to be
dated November 3, 2003 covering October, November, and December 2003,
will reflect the Rent amounts at the new rates specified in this Lease
Amendment No. 12.  A. Rent for LF/LH-l for the Second and Last
Extension Term shall be Five-Million Seven-Hundred Thirty-Nine Thousand
Five-Hundred Forty and 00/100 Dollars ($5,739,540.00), payable in equal
quarterly installments of Two-Hundred Eighty-Six Thousand Nine-Hundred
Seventy-Seven and 00/100 Dollars ($286,977.00), which is three times the Basic
Monthly Rent of Ninety-Five Thousand Six-Hundred Fifty-Nine and 00/100 Dollars
($95,659.00). (For information purposes only, Basic Rent for


LF/LH-1 is equivalent to a rounded unit rate
of $30.86 per rentable square foot per year.)  B.Rent for L00l for the Second and Last
Extension Term shall beNinety-Four
Thousand Fifty-Three and 00/100 Dollars ($94,053.00),payable in equal quarterly
installments of Four-Thousand Seven-Hundred Two and 65/100 Dollars ($4,702.65),which is three times the Basic Monthly Rent of One-Thousand
Five-Hundred Sixty-Seven and 55/100 Dollars ($1,567.55).(For
information purposes only, Basic Rent for L00l is equivalent to a rounded unit
rate of $13.46 per rentable square foot per year.)  C.Rent for
PC121 & PC123 for the Second and Last Extension Term shall be
Thirty-Three Thousand Eight-Hundred Ninety-Seven and 00/100 Dollars
($33,897.00), payable in equal quarterly installments of One-Thousand
Six-Hundred Ninety-Four and 85/100 Dollars ($1,694.85), which is three times
the Basic Monthly Rent of Five-Hundred Sixty-Four and 95/100 Dollars ($564.95).(For information purposes only, Basic Rent for PC121 &
PCI23 is equivalent to a rounded unit rate of $21.32 per rentable square foot
per year.)  D.Rent
for PF/NE (inside) for the Second and Last Extension Term shall be Six-Hundred
Twenty-Six Thousand Two-Hundred Fifty-Three and 00/100 Dollars($626,253.00),
payable in equal quarterly installments of Thirty-One Thousand Three-Hundred
Twelve and 65/100 Dollars ($31,312.65),which is three times the Basic
Monthly Rent of Ten-Thousand Four-Hundred Thirty-Seven and 55/100 Dollars ($10,437.55).(For information purposes only, Basic Rent for PF/NE
(inside) is equivalent to a rounded unit rate of $27.49 per rentable square
foot per year.)  E.Rent for PF/NE
(outside) for the Second and Last Extension Term shall be Sixty-One Thousand
Four-Hundred Thirty-Seven and 00/100 Dollars ($61,437.00), payable in equal
quarterly installments of Three-Thousand Seventy-One and 85/100 Dollars ($3,071.85),which is three times One-Thousand Twenty-Three and 95/100
Dollars ($1,023.95).(For information purposes only,
Basic Rent for PF/NE (outside) is equivalent to a rounded unit rate of $6.17
per rentable square foot per year.)  5.Utility Charges  Section 6.05 Utility Charges and
those certain associated Lease Amendments and Exhibits, as specified below, are
amended as follows.  1) The following Sections and/or Exhibits
shall be deleted:  ·Exhibit F-2 as referred in Section 6.05
Utility Charges of the Lease (within the second paragraph on page 14). ·Exhibit F-6 as referred to in item 10.
Section 6.05 Utility Charges of Lease Amendment No. 1 (on page 3).


·The text of item 7. Section 6.05 Utility
Charges of Lease Amendment No. 5(on page 4). ·Page 4/5 and Page 5/5 of LA5S-Exhibit D,
and LA5-Exhibit E also as referred to in item 7. Section 6.05 Utility
Charges of Lease Amendment No. 5(on page 4). ·LA5-Exhibit-F4 as referenced in item 8. Section 6.05
Utility Charges of Lease Amendment No. 5(on page 4)
....are
all deleted and replaced with the following, of which the replacement exhibit
is attached hereto.  2) The above-identified deletions shall be
replaced with the following:  (a)With reference to the
Demised Premises commonly known and referred to as LF/LH-1 and PF/NE  ·Tenants
adjusted utility charge usage for this Second and Final Five (5) Year Term shall be based on
the estimated usage for the Demised Premises commonly known and referred to as
LF/LH-1 and PF/NE. This estimated usage basis is calculated from an analysis of
2003 usage data for both areas, the sum of which shall constitute the usage
basis for future Utility Charges to Tenant, and is specified as 2003 Base Year
Usage. The new 2003 Base Year Usage applied to current 2003 projected usage
rates, and resultant adjusted charges are depicted and compared with pre-Lease
Amendment No. 12 data in the attached (LA 12-Exhibit F-l2).  ·2003
Base Year Usage data applied to projected utility rates shall be used to
calculate Tenants future projected annual Utility Charges for the Lease Term
commencing October 1, 2003. The 2003 Base Year Usage will remain in
force until such time that a substantial change is appropriate, and a
subsequent Lease Amendment executed.  (b)With reference to the
Demised Premises commonly known as L00l  Utilities (Lighting, HVAC) for the Demised Premises commonly known
L00l will continue to be charged at a fixed rate of Three-Hundred and 00/100
Dollars ($300.00) per year. In accordance with exhibit LAS-Exhibit-E.
Utility Charges, L00l in Lease Amendment No. 5,and as a result
of Medarexs use of the L00l space for other than general storage, actual
monthly metered electrical power consumption resulting from the additional
activities within L00l will be charged as Optional Services - Usage at the then
current power rate. This charge will be included in the existing monthly report
of charges provided by the Landlord to Tenant, titled Medarex House Utilities,
which includes Tenants usage charge of house gases.


ALL OTHER
TERMS AND CONDITIONS of the Lease Agreement remain unchanged and in full force
and effect.  LANDLORD:  EXXONMOBIL
RESEARCH AND ENGINEERING COMPANY  By:
  /s/ F. Emil JacobsPrint Name:  F. Emil JacobsTitle:Vice
  President, Research & DevelopmentDate:  9/20/03TENANT:MEDAREX, INC.By:
  /s/
  Christian S. SchadePrint Name: Christian S. SchadeTitle:  SVP/CFODate:  9/26/03


AMENDMENT No. 13  LEASE AMENDMENT (Lease Amendment) made as
of this 24thday of January 2004, to that certain Lease
Agreement dated as of May 6, 1993between ExxonMobil
Research and Engineering Company) (Landlord) and Medarex, Inc. (Tenant) as amended (Lease Agreement)  WHEREAS the
parties desire to amend the Lease Agreement to reflect the revised Base Rent in
accordance with Lease Amendment No.12 for one (1) five year renewal period
extending from October 1, 2003 through September 30, 2008 (the
Second and Final Five (5) Year
Tern).  NOW,THEREFORE the
parties agree to the following.  1.Base Rent  Allof item 4.
Rent, of Amendment No.12 and Lease Renewal SHALL BE DELETEDAND REPLACED WITH THE FOLLOWING:  Base Rent  The total Base
Rent payment for the Demised Premises for the Second and Final Five (5) Year Term shall be
Six-Million Five-Hundred Twenty-Seven Thousand Seven-Hundred Twenty-Nine and
40/100 Dollars ($6,527,729.40)payable
in equal quarterly installments of Three-Hundred Twenty-Six Thousand
Three-Hundred Eighty-Six and 47/100 Dollars ($326,386.47) as explained in further detail below, in Items A,
B, C, D and E.  A.Base Rent for
LF/LH-l for the Second and Last Extension Term shall be Five-Million
Seven-Hundred Fifteen Thousand Five-Hundred One and 00/100 Dollars ($5,715,501.00),payable in equal quarterly installments of
Two-Hundred Eighty-five Thousand Seven-Hundred
Seventy-Give and 05/100 ($285,775.05),which
is thee times the Basic Monthly Rent Of Ninety-Five Thousand Two-Hundred Fifty-Eight and 35/100
Dollars ($95,258.35).(For information purposes only,
Basic Rent for LF/LH-1 is equal to a rounded unit rate of $30.73 per rentable
square foot per year.)  B.Base Rent for
L00l for the Second and Last Extension Term shall be Ninety-Three Thousand
Six-Hundred Sixty and 00/1 00 Dollars ($93,660.00), payable in equal quarterly
installments of Four-Thousand Six-Hundred Eighty-Three and 00/100 Dollars
($4,683.00), which is thee times the Basic Monthly Rent of One-Thousand
Five-Hundred Sixty-One and 00/100 Dollars ($1,561.00).(For
information purposes only, Basic Rent for L00l is equivalent to a rounded unit
rate of $l3.41 per rentable square foot per year.)  C.Base Rent
for PC121& PC123
for the Second and Last Extension Term shall be Thirty-Three Thousand
Seven-Hundred Fifty-Six and 60/100 Dollars ($33,756.60)


payable in
equal quarterly installments of One-Thousand Six-Hundred Eighty-Three and
83/100 Dollars ($1,687.83), which is three times the Basic Monthly Rent of
Five-Hundred Sixty-Two and 61/100 Dollars ($562.61). (For information purposes only, Basic Rent for PC121 &
PC123 is equivalent to a rounded unit rate of $21.23 per rentable square foot
per year.)  D.Base Rent for
PF/NE (inside) for the Second and Last Extension Term shall be Six-Hundred
Twenty-Three Thousand Six-Hundred Thirty-One and 60/100 Dollars ($623,631.60),
payable in equal quarterly installments of Thirty-One Thousand One-Hundred Eighty-One
and 58/100 Dollars ($31,181.58), which is thee times the Basic Monthly Rent of
Ten-Thousand Three-Hundred Ninety-Three and 86/100 Dollars ($10,393.86). (For
information purposes only, Basic Rent for PF~E (inside) is equivalent to a
rounded unit rate of $27.33 per rentable square foot per year.)  E.Base Rent for PF/NE
(outside) for the Second and Last Extension Term shall be Sixty-one Thousand
One-Hundred Eighty and 20/100 Dollars ($61,180.20), payable in equal quarterly
installments of Three-Thousand Fifty-Nine and 01/100 Dollars ($3,059.01) which
is thee times the Basic Monthly
Rent of One-Thousand Nineteen and 67/100 Dollars ($1,019.67). (For information
purposes only, Basic Rent for PF/NE (outside) is equivalent to a rounded unit
rate of $6.15 per rentable square foot per year.)  2.Base Rent Adjustment, 4Q
2003    Also in
accordance with the Base Rent recalculation approach referenced in item 3.
 Recalculation Modification and
Additional Adjustment of the Amendment No.12 and Lease Renewal, such that the
now current CPI-U Index upward change of 11.74% (Percentage increase of the
Index from October 1993 of 170.3 to the Index of October 2003 of
190.3) shall be applied to constitute the adjustment in Base Rent Previously
charged in the fourth quarter 2003 invoice; and as indicated, this adjustment
shall be reflected in the first quarter 2004 invoice, and shall be described in
the invoice as Base Rent Adjustment 4Q 2003. This adjustment shall be a
credit to Tenant in the amount of One-Thousand Three-Hundred Seventy-Two and
53/100 Dollars ($1,372.53).  3.Utility
ChargesL001  With reference
to 5. Utility Chares of Amendment No.12 and Lease Renewal
specifically item 5., 2), (b) With reference to theDemised Premises commonly known as
L001,that specific item [5.,
2), (b)] SHALL BE DELETED IN ITS ENTIRETY AND REPLACED WITH THE
FOLLOWING:  Utilities for
the Demised Premises commonly known as L001 will be charged at a fixed rate of
Two-Thousand Five-Hundred and 00/100 Dollars ($2,500.00) per annum for the
estimated Electrical usage within room L001 for each year of the Five (5) Year Renewal Term as
described in Amendment 12 and Lease Renewal This annual amount is comprised
of two Electrical usage categories within L001.Tenant
Equipment and


HVAC /
Lighting, which are described in the attached Exhibit (LA13.Exhibit F-l3b)
This fixed rate shall remain in force until such time as both parties mutually
agree per Lease Amendment to modify the said amount.  4.Utility
ChargesLA12-Exhibit F-12  With reference
to 5. Utility Charges of
Amendment No.12 and Lease Renewal,specifically
item 5., 2),(a),onlythe associated Exhibit (LA12-Exhibit F-l2)
SHALL BE DELETED IN ITS ENTIRETY AND REPLACED WITH the attached Exhibit (LA13-Exhibit F-13a)  (For information purposes only, the new Exhibit is
only modified to reflect the change in the Utility charge related to L001, as
described above in item 3.)  ALL OTHER TERMS AND CONDITIONS of the Lease
Agreement remain unchanged and in full force and effect.  LANDLORD:EXXONMOBIL RESEARCH AND ENGINEERING COMPANYBy:
  /s/
  F.E. JacobsPrint:
  F.E. JacobsTitle:
  Vice PresidentDate: 1/24/04TENANT:MEDAREX, INC.By:
  /s/
  Christian S. SchadePrint:
  Christian S. SchadeTitle:
  CFODate:
  1/9/04


AMENDMENT No.14  LEASE AMENDMENT (Lease Amendment) made as
of this 22nd day of  June 2004, to
that certain Lease Agreement dated as of May 6, 1993 between ExxonMobil Research and Engineering Company)(Landlord),
and Medarex, Inc.(Tenant)
as amended (Lease Agreement).  WHEREAS, the
parties desire to amend the Lease Agreement for the term commencing July 1,
2004 through September 30, 2008 (which is the expiration date of the now
current Second and Final Five (5) Year Term);  WHEREAS,
Tenant wishes Landlord to approve the installation of a single Standby
Generator and to lease additional space from Landlord for this purpose for the
specified Lease Amendment term; and  WHEREAS,
Landlord is willing to make such additional space available for lease to Tenant
on the same terms and conditions as are set forth in the Lease Agreement,
subject only to the modifications set forth below:  NOW,
THEREFORE, the parties agree to the following:  1.   The Demised Premises, as defined in Item 1. Demised
Premises of the Lease Amendment No. 12 and Lease Renewal, are enlarged
for the term of this Lease Amendment No. 14 by the addition of:  A. The area designated as the South End, South-East Exterior Corner, of
the PE-Wing of the Pilot Plant, adjacent to and south of one of ExxonMobils
Tenants standby / emergency generators, which additional space is deemed to be
270 rentable square feet, being more particularly described on LA14-Exhibit A
attached hereto, (hereinafter, Standby Generator Pad, on which the Standby Generator
shall be installed).  B. The area designated as Room L037,
located in the 0 Level of the Laboratory Building, which additional space is
deemed to be 370 rentable square feet, being more particularly described on
LA14-Exhibit B attached hereto, (hereinafter, L037). L037 SHALL NOT be
temporarily or permanently used for any purpose other than to house electrical
components in support of the Standby Generator system. This use prohibition
includes, but is not limited to its use as an office, file room, conference
room, or for the storage of any chemicals or materials, whether hazardous or
not. If the Tenant desires to use L037 for anything other than as a space to
house Standby Generator system components, Tenant may submit to Landlord a
request to approve other possible uses and Landlord will have sole authority to
accept or reject such requests, without the need for any explanation


thereof, and shall respond to Tenant in
writing.  2. Base Rent   A. The Standby Generator Pad shall be leased and appropriate space made
available for electrical cable routing between the Emergency Generator and
L037, without increasing the Base Rent paid quarterly (which, for informational
purposes only, is at the current quarterly paid rate indicated in Lease Amendment
No. 13 of Three-Hundred Twenty-Six Thousand Three-Hundred Eighty-Six and
47/100 Dollars ($326,386.47)).  B. L037 shall be leased at the annual Base Rent of Four-Thousand
Nine-Hundred Sixty-One and 64/100 Dollars ($4,961.64 per year), payable in
quarterly installments of One-Thousand Two-Hundred Forty and 41/100 Dollars
($1,240.41), which is three times the Basic Monthly Rent of Four-Hundred
Thirteen and 47/100 Dollars ($413.47). (For information purposes only, Base
Rent for L037 is equivalent to a rounded unit rate of $13.41 per rentable
square foot per year.)  C. As a result of the increase in Base Rent due to the addition of
L037, as described above in Item 2. B., the total Base Rent for the
total Demised Premises, as described in the first paragraph under Item 1. Base
Rent........Base Rent on Page 1 of Lease Amendment No. 13,
SHALL BE INCREASED by the amount set forth above in Item 2. B..  3. Additional Rent   The
Additional Rent, as traditionally calculated based on Tenants leased space in rentable
square feet, which specifically includes Tenants apportioned share of the Real Estate Taxes, Operating Expenses, and Imputed Insurance, SHALL INCREASE by 0.08% for each
Additional Rent category as defined in this item. Therefore, Real Estate Taxes
will increase from 5.89% to 5.97%, and Operating Expenses and Imputed Insurance
will each increase from 5.63% to 5.71%.  4. Potential Change: Standby Generator and/or Location  In the
future, if Landlord so requests and after providing reasonable advanced written
Notice to Tenant (i.e., not less than 6 months), Tenant shall be required to
bring its Standby Generator and Standby Generator Pad into compliance with the
electrical classification specified as Class 1, Div. 2, Group C &
D by a date specified by Landlord at time of the request. Compliance measures
shall be initiated and completed by Tenant and may include, but are not limited
to, Tenants upgrade or replacement of Standby Generator, or relocation to a
Landlord-approved non-classified physical location, or Tenant will not use the
Standby Generator until appropriate compliance measures are complete. Measures
to be taken by Tenant shall be approved in writing by Landlord prior to
implementation, and Tenants compliance with the above-stated electrical
reclassification requirements shall be accomplished with timing of the essence.
All costs and/or liabilities of such measures shall be the sole responsibility
of Tenant.  5.Landlord disclaims any warranties of any
kind, expressed or implied, associated with


the installation and/or operation of this
Standby Generator, and/or associated materials, equipment and systems.  ALL OTHER
TERMS AND CONDITIONS of the Lease Agreement remain unchanged and in full force
and effect.   LANDLORD: EXXONMOBIL
RESEARCH AND ENGINEERNG COMPANY   By:
  /s/ F. Emil
  JacobsPrint Name:
  F. Emil JacobsTitle:
  Vice President of
  Research & DevelopmentDate:
  6/22/04TENANT:MEDAREX, INC.By:
  /s/
  Christian S. SchadePrint Name:
  Christian S.
  SchadeTitle:
  CFODate:
  6/17/04


AMENDMENT No.15 and LEASE EXTENSION  This AMENDMENT No. 15 and LEASE
EXTENSION (15th Amendment), is made and entered into as of this 31st day of
January, 2006, to that certain Lease Agreement dated as of May 6, 1993 by
and between ExxonMobil Research and Engineering Company,
formerly known as Exxon Research and Engineering Company, a Delaware
corporation (Landlord), and Medarex, Inc.,
a New Jersey corporation (Tenant), as amended by Amendments No. 1
through No. 14 (collectively, the Lease Agreement).  WHEREAS, the parties agree that certain
provisions of the Lease Agreement, as identified below, should be amended; and  WHEREAS, the parties desire to extend the
Lease Agreement as herein amended for an additional period extending from October 1,
2008 through December 4, 2011 (Extension Term).  NOW, THEREFORE, in consideration of the
mutual covenants of the parties and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties agree
that the Lease Agreement is hereby amended and the term thereof extended as
follows:  1.Demised
Premises; Annual and Quarterly Base Rent  The Demised Premises, associated Rentable
Square Footages, Base Rent per Rentable Square Footages, current quarterly Base
Rent, current annual Base Rent are summarized as follows:  Demised Premises
  
  Per
  Lease
  Amendment
  No.
  
  Rentable
  Square
  Feet
  
  Current
  Base
  Rental
  Rate
  
  Quarterly
  Base Rent
  
  Annual Base
  RentLF/LH-1
  
  7
  
  37,200
  
  $
  30.73
  
  $
  285,775.05
  
  $
  1,143,100.20L00l
  
  7
  
  1,397
  
  $
  13.41
  
  $
  4,683.00
  
  $
  18,732.00L037
  
  14
  
  370
  
  $
  13.41
  
  $
  1,240.41
  
  $
  4,961.64PC121 & PC123
  
  8
  
  318
  
  $
  21.23
  
  $
  1,687.83
  
  $
  6,751.32PF/NE (inside)
  
  7
  
  4,556
  
  $
  27.38
  
  $
  31,181.58
  
  $
  124,726.32PF/NE (outside)
  
  7
  
  1,991
  
  $
  6.15
  
  $
  3,059.01
  
  $
  12,236.04Generator Pad
  
  14
  
  270
  
  $
  0.00
  
  $
  0.00
  
  $
  0TOTALS:
  
  
  
  46,102
  
  
  
  $
  327,626.88
  
  $
  1,310,507.52


2.Extension
of Term  The Term of the Lease is hereby extended for
an additional period of thirty-eight (38) months and four (4) days,
commencing October 1, 2008 and expiring December 4, 2011, unless
sooner terminated pursuant to the terms of the Lease Agreement.  3.Extension
Term Base Rent  Effective October 1, 2008 and continuing
unchanged throughout the Extension Term, the Base Rent will be as shown on the
table below. Notwithstanding any other provision in the Lease, Base Rent during
the Extension Term will not be subject to any escalation or other adjustments,
but shall be fixed at the rates shown below.  Demised Premises
  
  Rentable
  Square Feet
  
  Extension
  Term Base
  Rental Rate
  
  Quarterly Base
  Rent
  
  Annual Base
  RentLF/LH-l
  
  37,200
  
  $
  43.00
  
  $
  399,900.00
  
  $
  1,599,600.00L00l
  
  1,397
  
  $
  18.75
  
  $
  6,548.44
  
  $
  26,193.75L037
  
  370
  
  $
  18.75
  
  $
  1,734.38
  
  $
  6,937.50PCI2I& PC123
  
  318
  
  $
  29.75
  
  $
  2,365.13
  
  $
  9,460.50PF/NE (inside)
  
  4,556
  
  $
  38.35
  
  $
  43,680.65
  
  $
  174,722.60PF/NE (outside)
  
  1,991
  
  $
  8.60
  
  $
  4,280.65
  
  $
  17,122.60Generator Pad
  
  270
  
  $
  0.00
  
  $
  0.00
  
  $
  0.00TOTALS:
  
  46,102
  
  
  
  $
  458,509.25
  
  $
  1,834,036.95  The total Base Rent to be paid for the
Demised Premises for the Extension Term shall be Five Million Eight Hundred
Twenty-six Thousand Fifty-seven and 59/100 Dollars ($5,826,057.59),payable
in equal quarterly installments of Four Hundred Fifty-eight Thousand Five
Hundred Nine and 25/100 Dollars ($458,509.25),as summarized above and as
explained in further detail below in subparagraphs 4-A, B, C, D, E, F, and G.
The quarterly invoices are dated and released on or about the first working day
of February, May, August, and November per annum. Each quarterly invoice
encompasses the charges for Base Rent and Additional Rent for a calendar
quarter, where, for example, the February 2009 invoice (the 1a-2009
Invoice) will cover these charges for January, February, and March 2009.
Each quarterly invoice also encompasses Optional Services -Usage charges
reported for the previous three (3) months. The 4Q-2008 Invoice to be
dated November 2008, covering October, November, and December 2008,
will reflect the Base Rent amounts at the new rates specified in this 15th
Amendment. The Base Rent payment for the last partial quarter of the Extension
Term (October 1, 2011 through December 4, 2011) shall be Three
Hundred Twenty-three Thousand Nine Hundred Forty-six and 74/100 Dollars
($323,946.74).  A.            Annual Base Rent for LF/LH-1 for the Extension Term shall
be One Million Five


Hundred Ninety-nine Thousand Six Hundred and
No/l00 Dollars ($l,599,600.00), payable in equal quarterly installments of
Three Hundred Ninety-nine Thousand Nine Hundred and No/100 Dollars
($399,900.00), which is three times the Basic Monthly Rent of One Hundred
Thirty-three Thousand Three Hundred and No/100 Dollars ($133,300.00). (For
information purposes only, Base Rent for LF/LH-1 is equivalent to a rounded
unit rate of Forty-three and No/1 00 Dollars ($43.00) per rentable square foot
per year.)  B.            Annual Base Rent for L001 for the Extension Term shall be
Twenty-six Thousand One Hundred Ninety-three and 75/100 Dollars ($26,193.75),
payable in equal quarterly installments of Six Thousand Five Hundred
Forty-eight and 44/100 Dollars ($6,548.44), which is three times the Basic
Monthly Rent of Two Thousand One Hundred Eighty-two and 8 1/100 Dollars
($2,182.81). (For information purposes only, Base Rent for L00l is equivalent
to a rounded unit rate of Eighteen and 75/100 Dollars ($18.75)per
rentable square foot per year.)  C.            Annual Base Rent for L037 for the Extension Term shall be
Six Thousand Nine Hundred Thirty-seven and 50/100 Dollars ($6,937.50), payable
in equal quarterly installments of One Thousand Seven Hundred Thirty-four and 3
8/100 Dollars ($1,734.38), which is three times the Basic Monthly Rent of Five
Hundred Seventy-eight and 13/100 Dollars ($578.13).(For information purposes only,
Base Rent for L037 is equivalent to a rounded unit rate of Eighteen and 75/100
Dollars ($18.75) per rentable square foot per year.)  D.            Annual Base Rent for PC121 & PC123 for the
Extension Term shall he Nine Thousand Four Hundred Sixty and 50/100 Dollars
($9,460.50), payable in equal quarterly installments of Two Thousand Three
Hundred Sixty-five and 13/100 Dollars ($2,365.13), which is three times the
Basic Monthly Rent of Seven Hundred Eighty-eight and 38/100 Dollars ($788.38),
(For information purposes only, Base Rent for LF/LH-1 is equivalent to a
rounded unit rate of Twenty-nine and 75/100 Dollars ($29.75) per rentable
square foot per year.)  E.             Annual Base Rent for PF/NE (inside) for the Extension
Term shall be One Hundred Seventy-four Thousand Seven Hundred Twenty-two and
60/100 Dollars ($174,722.60), payable in equal quarterly installments of
Forty-three Thousand Six Hundred Eighty and 65/100 Dollars ($43,680.65),which is three times the Basic Monthly Rent of Fourteen
Thousand Five Hundred Sixty and 22/100 Dollars ($14,560.22). (For information
purposes only, Base Rent for LF/LH-1 is equivalent to a rounded unit rate of
Thirty-eight and 35/100 Dollars ($38.35) per rentable square foot per year.)  F.             Annual Base Rent for PF/NE (outside) for the Extension
Term shall be Seventeen Thousand One Hundred Twenty-two and 60/100 Dollars
($17,122.60), payable in equal quarterly installments of Four Thousand Two
Hundred Eighty and 65/100 Dollars ($4,280.65), which is three times the Basic
Monthly Rent of One Thousand Four Hundred Twenty-six and 88/100 Dollars
($1,426.88). (For information purposes only, Base Rent for LF/LH-1 is
equivalent to a rounded unit rate of Eight and 60/100 Dollars


($8.60) per rentable square foot per year.)  G.            Annual Base Rent for the Generator Pad for the Extension
Term shall be Zero Dollars ($0.00).  ALL OTHER TERMS AND CONDITIONS of the Lease Agreement remain unchanged
and in full force and effect.  IN WITNESS WHEREOF, the authorized representatives of each of the
parties have hereby executed this Amendment No. 15 and Lease Extension to
be effective as of the 31st day of January, 2006.   LANDLORD: EXXONMOBIL
RESEARCH AND ENGINEERING COMPANY, a Delaware
corporation   By:
  /s/ F. Emil JacobsName:
  Fritz Emil JacobsTitle:
  Vice PresidentTENANT:MEDAREX, INC.,a New Jersey
  corporationBy:
  /s/ Christian S. SchadeName:
  Christian S. SchadeTitle:
  CFO


AMENDMENT No. 16  and LEASE EXTENSION  This AMENDMENT No. 16 and LEASE EXTENSION (16th Amendment), is
made and entered into as of this 24th day of October, 2008, to that certain
Lease Agreement dated as of May 6, 1993 by and between ExxonMobil Research and Engineering Company, formerly known
as Exxon Research and Engineering Company, a Delaware corporation (Landlord),
and Medarex, Inc., a New Jersey
corporation (Tenant), as amended by Amendments No. 1 through No. 15
(collectively, the Lease Agreement).  WHEREAS, the parties agree that certain provisions of the Lease
Agreement, as identified below, should be amended; and  WHEREAS, the parties desire to extend the Lease Agreement as herein
amended for an additional period extending from December 5, 2011, through December 31,
2013 (16th Amendment Extension Term).  NOW, THEREFORE, in consideration of the mutual covenants of the parties
and other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties agree that the Lease Agreement is hereby
amended and the term thereof extended as follows:  1.Extension
of Term.  The Term of the Lease Agreement is hereby extended for an additional
period of twenty-four (24) months and twenty-six (26) days, commencing December 5,
2011 and expiring December 31, 2013, unless sooner terminated pursuant to
the terms of the Lease Agreement.  2.Base
Rent for First Extension Term and 16th Amendment Extension Term.  Effective October 1, 2008, the Base Rent for the Premises will no
longer be determined on the basis of location and use of the particular areas
within the Premises.  Therefore, the rent
table and other provisions in Section 3 of Amendment No. 15 and Lease
Extension are hereby deleted in their entirety, effective as of October 1,
2008, and replaced with the following statements of Base Rent:  Effective October 1, 2008 and continuing unchanged throughout the
first Extension Term, the annual Base Rent will be increased to Two Million Two
Hundred One Thousand Two Hundred Thirty-Three and 20/100 Dollars
($2,201,233.20), payable in equal quarterly installments of Five Hundred Fifty
Thousand Three Hundred Eight and 30/100 Dollars ($550,308.30) per quarter,
payable on the first day of each calendar quarter.  The first quarterly payment for the first
Extension Term will be equitably prorated.  Effective December 5, 2011 and continuing unchanged throughout the
16th


Amendment Extension Term, the annual Base Rent will be increased to Two
Million Eight Hundred Sixty-One Thousand Six Hundred Three and 16/100 Dollars
($2,861,603.16), payable in equal quarterly installments of Seven Hundred
Fifteen Thousand Four Hundred and 79/100 Dollars ($715,400.79) per quarter,
payable on the first day of each calendar quarter.  The first quarterly payment for the 16th
Amendment Extension Term will be equitably prorated.  The quarterly invoices are dated and released on or about the first
working day of February, May, August, and November per annum.  Each quarterly invoice encompasses the
charges for Base Rent and Additional Rent for a calendar quarter, where, for
example, the February 2009 invoice will cover these charges for January,
February, and March 2009.  Each
quarterly invoice also encompasses Optional Services - Usage charges reported
for the previous three (3) months. 
By way of example only, the 4Q-2008 Invoice to be dated November 2008,
covering October, November, and December 2008, will reflect the Base Rent
amounts at the new rate specified in this 16th Amendment.  3.Calculation
of Additional Rent.  Section 6.04, Optional Services, of the Lease Agreement is deleted
in its entirety and replaced with the following:  Section 6.04  ADDITIONAL SERVICES  Landlord offers additional services in each of the following two
categories, as indicated in Exhibit D hereto: (1) Predetermined Usage
and (2) Headcount.  (1)Predetermined
Usage: Annual rates to be charged for each predetermined service used shall
become effective as of the first day of January of each year of the Lease
Term.  Landlord shall provide Tenant with
the new annual rates by December 01 of each prior year.  Adjustments, if any, will appear in the
second quarterly invoice.  Landlord may
change a rate or cancel a service at any time by giving Tenant not less than
thirty (30) days notice, in which event Tenants liability for charges for the
cancelled service shall be prorated to the last day of the service.  Tenant shall also have the right to cancel
any predetermined service upon thirty (30) days prior written notice to the
Landlord.  (2)Headcount:
Landlord shall set annual rates and advise Tenant as set forth in (1) immediately
above, except that Landlord shall not be entitled to cancel the service.  Not later than January 02 of each year,
Tenant shall advise Landlord of its projected average headcount (number of
full-time employees and/or contractors) for the upcoming year of the Lease
Term.  Tenant shall promptly advise
Landlord if the average headcount departs materially from Tenants projection.  On the first day of the second month of each quarter, Landlord shall
provide


Tenant with a quarterly invoice including Tenants predetermined usage
payment, inclusive of categories (1) and (2) above, and Tenant shall
pay the invoice amount by the 15th day of that month.  Quarterly payments may be made by electronic
wire transfer.  Proposed project work must be requested in writing to Landlord
Facilities Manager.  Project work may
only commence upon review and written approval by Landlord Facilities Manager.
Tenant is expected to directly contract services from third party vendors,
chosen from Landlords approved list.  If
Tenant chooses to contract the services from third party vendors that are not
on Landlords approved list, Tenant must seek Landlord approval to include
contractor on Landlords list of approved vendors and produce proof that
contractor has successfully completed required safety training, background
checks, and drug and alcohol testing, and any other requirements prescribed by
Landlord.  Associated costs for these
requirements are to be borne by the Tenant.  4.No
Other Modifications; Counterpart Signatures.  The Lease
Agreement, as amended hereby, remains in full force and effect without any
further amendments, alterations or modifications thereto except as expressly
set forth herein, and Landlord and Tenant expressly ratify and confirm the
Lease Agreement as amended by this 16th Amendment.  This Lease Agreement may not be further
modified except in a written instrument signed by the authorized
representatives of each party hereto. All initially capitalized words and terms
used herein shall have the meanings ascribed to them in the Lease Agreement,
unless otherwise specifically provided herein. 
This Lease Agreement may be executed in multiple counterparts, and by
either or both of the parties hereto in separate counterparts, each of which
when executed and delivered shall constitute an original but all of which taken
together shall constitute one and the same agreement.  [Signatures appear on following page.]


IN WITNESS WHEREOF, the authorized representatives of each of the
parties have hereby executed this Amendment No. 16 and Lease Extension to
be effective as of the 24th day of October, 2008.   LANDLORD: EXXONMOBIL RESEARCH AND ENGINEERING COMPANY, a Delaware corporation  By:
  /s/ F. Emil JacobsName:
  Fritz Emil JacobsTitle:
  Vice PresidentTENANT:MEDAREX, INC.,a New Jersey
  corporationBy:
  /s/ Christian S. SchadeName:
  Christian S. SchadeTitle:
  CFO