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                                                                    EXHIBIT 10.9

                            SECOND AMENDMENT TO LEASE

            THIS SECOND AMENDMENT (hereinafter referred to as the "AGREEMENT" or
the "Amendment") is made as of the 28th day of December, 1999 between 450
WESTSIDE PARTNERS, LLC, a Delaware limited liability company having an office at
230 Park Avenue, New York, New York 10169, successor in interest to John Hancock
Mutual Insurance Company (hereinafter referred to as "HANCOCK"), (hereinafter
referred to as "LANDLORD") and DOUBLECLICK, INC., a Delaware corporation, having
an office at 450 West 33`d Street, New York, New York 10001 (hereinafter
referred to as "TENANT").

                              W I T N E S S E T H:

            WHEREAS, pursuant to a certain Agreement of Lease dated as of
January 26, 1999 between Hancock and Tenant, as amended by an Amendment to Lease
and letter agreement, each made as of January 26, 1999, as further modified by
letter agreement dated June 8, 1999, and letters dated June 18, 1999, June 29,
1999 and July 12, 1999 (hereinafter collectively referred to as the "LEASE"),
Tenant is the tenant of certain premises consisting of space on the sixteenth
(16th) floor, loading bay #21 and freight elevator #F-8 and the area on the east
and west sides of the rooftop/set back outside the windowed portions of the 16th
floor (hereinafter collectively referred to as the "16TH PREMISES") and the
twelfth (12th) floor, loading bay # 18 and freight elevator # F-13 (hereinafter
collectively referred to as the "12TH PREMISES") in the building located at 450
West 33rd Street, New York, New York (hereinafter referred to as the "BUILDING")
(the 16th Premises and the 12th Premises are hereinafter collectively referred
to as the "EXISTING PREMISES"); and

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            WHEREAS, Landlord and Tenant desire to extend the term of the Lease
with respect to the Existing Premises and to add to the Existing Premises
additional space on the fourteenth (140 floor (hereinafter referred to as the
"14TH PREMISES") and the fifteenth (15TH) floor, loading bay #22 and freight
elevator # F-7 (hereinafter collectively referred to as the "15TH PREMISES") of
the Building which the parties hereto agree that the 14th Premises and the 15th
Premises shall each be deemed to consist of approximately 104,562 rentable
square feet (the 14th Premises and the 15th Premises are collectively
hereinafter referred to as the "ADDITIONAL PREMISES") on the terms and
conditions hereinafter set forth.

            NOW THEREFORE, for and in consideration of the rental payments to be
made hereunder by Tenant to Landlord and the mutual consideration hereinafter
set forth, Landlord and Tenant now desire to amend the Lease upon the terms and
conditions as follows (all capitalized terms used herein (but not otherwise
defined herein and which are defined in the Lease) shall have the meanings
ascribed to such terms in the Lease unless otherwise expressly set forth
herein):

            FIRST: Landlord and Tenant hereby agree that the Lease is hereby,
extended to and shall end at noon of the last day of the calendar month in which
occurs the day. preceding the fifteenth (15th) anniversary of the Commencement
Date (as hereafter defined), which ending date is hereinafter referred to as the
"EXPIRATION DATE", or shall end on such earlier date: upon which said term may
expire or be cancelled or terminated pursuant to any of the conditions or
covenants of the Lease, this Amendment or pursuant to law.

            SECOND: (a) (a) Effective upon the date a fully executed copy of
this Amendment is delivered by Landlord to Tenant (hereinafter referred to as
the "COMMENCEMENT DATE"), Landlord shall deliver possession to Tenant of a
portion of the 14th Premises consisting

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of approximately 51,959 rentable square feet (hereinafter referred to as the
"UNIT A PREMISES") as shown on the floor plan annexed hereto as Exhibit A, and
the Unit A Premises shall be deemed to be part of the Existing Premises as set
forth herein from such Commencement Date through and including the Expiration
Date (including any renewals thereof pursuant to Article 53 of the Lease).

                  (b) Effective upon the date (hereinafter referred to as the
"UNIT B COMMENCEMENT DATE") upon which broom clean possession of the Unit B
Premises (as hereafter defined) is available to Tenant and Landlord has given
five (5) days' prior written notice thereof to Tenant (which notice,
notwithstanding anything in the Lease or herein to the contrary, may be sent by
hand delivery), a portion of the 14th Premises consisting of approximately
19,989 rentable square feet (hereinafter referred to as the "UNIT B PREMISES")
as shown on the floor plan annexed hereto as Exhibit B shall be deemed to be
part of the Existing Premises as set forth herein through and including the
Expiration Date (including any renewals thereof pursuant to Article 53 of the
Lease). Notwithstanding anything hereinabove or in this Agreement: to the
contrary, in the event that the Unit B Commencement Date has not occurred by
April 1, 2000, Tenant shall be entitled to a fixed rent abatement (in addition
to any other abatement of rent to which Tenant is entitled hereunder or under
the Lease) of a/z day's fixed rent otherwise payable with respect to the Unit
B Premises for each day beyond April 1, 2000 that the Unit B Commencement Date
fails to occur. In the event that the Unit B Commencement Date has not occurred
by June 1, 2000, Tenant shall be entitled to a fixed rent abatement (in addition
to any other abatement of rent to which Tenant is entitled hereunder or under
the Lease) of one (1) day's fixed rent otherwise payable with respect to the
Unit B Premises for each day beyond June 1, 2000 that the Unit B Commencement
Date fails to occur. The foregoing shall be

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Tenant's sole remedy for the failure of the Unit B Commencement Date to occur by
the dates set forth in this paragraph (b).

            (c) Effective upon the date (hereinafter referred to as the "UNIT C
COMMENCEMENT DATE") upon which broom clean possession of the Unit C Premises (as
hereafter defined) is available to Tenant and Landlord has given five (5) days'
prior written notice thereof to Tenant (which notice, notwithstanding any in the
Lease or herein to the contrary, may be sent by hand delivery), a portion of the
14th Premises consisting of approximately 32,614 rentable square feet
(hereinafter referred to as the "UNIT C PREMISES") as shown on the floor plan
annexed hereto as Exhibit C shall be deemed to be part of the Existing Premises
as set forth herein through and including the Expiration Date (including any
renewals thereof pursuant to Article 53 of the Lease). Any portion of the common
area contained in the 14th Premises not otherwise demised to Tenant on each of
the Unit A Commencement Date, the Unit B Commencement Date and/or the Unit C
Commencement Date shall, upon the Unit C Commencement Date, be deemed to be part
of the Existing Premises as set forth herein through and including the
Expiration Date (including any renewals thereof pursuant to Article 53 of the
Lease). Notwithstanding anything hereinabove or in this Agreement to the
contrary, in the event that the Unit C Commencement Date has not occurred by
January 1, 2004, Tenant shall be entitled to a fixed rent abatement (in addition
to any other abatement of rent to which Tenant is entitled hereunder or under
the Lease) of a 1/2 day's fixed rent otherwise payable with respect to the Unit
C Premises for each day beyond January 1, 2004 that the Unit C Commencement Date
fails to occur. In the event that the Unit C Commencement Date has not occurred
by March 1, 2004, Tenant shall be entitled to a fixed rent abatement (in
addition to any other abatement of rent to which Tenant is entitled hereunder or
under the Lease) of one (1) day's fixed rent

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otherwise payable with respect to the Unit C Premises for each day beyond March
1, 2004 that the Unit C Commencement Date fails to occur. The foregoing shall be
Tenant's sole remedy for the failure of the Unit C Commencement Date to occur by
the dates set forth in this paragraph (c).

            (d) Subject to the provisions of Article Fifth hereof, effective
upon the date (hereinafter referred to as the "15TH PREMISES COMMENCEMENT DATE")
upon which broom-clean possession of the 15th Premises is available to Tenant
and Landlord has given five (5) days' prior written notice thereof to Tenant
(which notice, notwithstanding anything in the Lease or herein to the contrary,
may be sent by hand delivery), the 15th Premises as shown on the floor plan
annexed hereto as Exhibit D shall be deemed to be part of the Existing Premises
as set forth herein through and including the Expiration Date (including any
renewals thereof pursuant to Article 53 of the Lease). Notwithstanding anything
hereinabove or in this Agreement to the contrary, in the event that the 15th
Premises Commencement Date has not occurred by July 1, 2003, Tenant shall be
entitled to a fixed rent abatement (in addition to any other abatement of rent
to which Tenant is entitled hereunder or under the Lease) of a %2 day's fixed
rent otherwise payable with respect to the 15th Premises for each day beyond
July 1, 2003 that the 15th Premises Commencement Date fails to occur. In the
event that the 15th Premises Commencement Date has not occurred by September 1,
2003, Tenant shall be entitled to a fixed rent abatement (in addition to any
other abatement of rent to which Tenant is entitled hereunder or under the
Lease) of one (1) day's fixed rent otherwise payable with respect to the 15th
Premises for each day beyond September 1, 2003 that the 15th Premises
Commencement Date fails to occur. Notwithstanding anything hereinabove to the
contrary, the parties agree that the 15th Premises Commencement Date shall not
occur prior to January 1, 2003.

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            (e) Except as otherwise provided in this Agreement, whenever in the
Lease reference is made to the "demised premises", "leased premises" or a
similar phrase, from and after each of the Commencement Date, the Unit B
Commencement Date, the Unit C Commencement Date, and the 15th Premises
Commencement Date, such phrases shall be deemed to include each of the Unit A
Premises, the Unit B Premises, the Unit C Premises, and the 15th Premises,
respectively, and, except as otherwise expressly set forth herein or in the
Lease, all the terms, covenants, and conditions of the Lease shall apply to the
aggregate of the Existing Premises and the Unit A Premises, the Unit B Premises,
the Unit C Premises, and the 15th Premises on each of the Commencement Date, the
Unit B Commencement Date, the Unit C Commencement Date, and the 15th Premises
Commencement Date, respectively. For purposes of the Unit A Premises, the Unit B
Premises, the Unit C Premises, and the 15th Premises only, the terms
"Commencement Date", "on the date of this lease", "on the date hereof' or any
such similar terms used in the Lease or in this Agreement shall mean the
Commencement Date, the Unit B Commencement Date, the Unit C Commencement Date,
and the 15th Premises Commencement Date, as applicable.

            THIRD: As same is applicable only to the Existing Premises and
continuing thereafter through the Expiration Date, the Lease shall be deemed
modified as follows: ,

            (A) Section 38(A)

                  (1) The amount of fixed rent for the 16th Premises provided in
Section 38(A)(1)(i) of the Lease shall be ONE MILLION SIX HUNDRED ELEVEN
THOUSAND FIVE HUNDRED FIFTY-TWO AND 00/100ths DOLLARS ($1,611,552.00)
($134,296.00 per month) and the phrase "the day immediately preceding the fifth
(5th) anniversary of the Rent

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                  Commencement Date" shall be deemed deleted therefrom and the
phrase "December 31, 2004" shall be deemed substituted in lieu thereof.

                  (2) The amount of fixed rent for the 16th Premises provided in
Section 38(A)(1)(ii) of the Lease shall be ONE MILLION SEVEN HUNDRED SIXTY-TWO
THOUSAND SIX HUNDRED THIRTY-FIVE AND 00/100ths DOLLARS ($1,762,635.00)
($146,886.25 per month) and the phrase "the fifth (5th) anniversary of the Rent
Commencement Date until the expiration of the term" shall be deemed deleted
therefrom and the phrase "January 1, 2005 through and including December 31,
2009" shall be deemed substituted in lieu thereof.

                  (3) The following shall be inserted in Article 38 of the Lease
as Section 38(A)(1)(iii) as fixed rent for the 16th Premises:

            "(iii) ONE MILLION NINE HUNDRED THIRTEEN THOUSAND SEVEN HUNDRED
            EIGHTEEN AND 00/100ths DOLLARS ($1,913,718.00) ($159,476.50 per
            month) for the period from January 1, 2010 and continuing thereafter
            throughout the remainder of the term of this lease."

                  (4) The amount of fixced rent for the 12'" Premises provided
in Section 38(A)(1)(i) of the Lease shall be THREE MILLION TWO HUNDRED THREE
THOUSAND SEVEN HUNDRED TWELVE AND 00/100ths DOLLARS ($3,203,712.00) ($266,976.00
per month) and the phrase "the day immediately preceding the fifth (5th)
anniversary of the Commencement Date" shall be deemed deleted therefrom and the
phrase "December 31, 2004" shall be deemed substituted in lieu thereof.

                  (5) The amount of fixed rent for the 12th Premises provided in
Section 38(A)(1)(ii) of the Lease shall be THREE MILLION FIVE HUNDRED FOUR
THOUSAND SIXTY AND 00/100ths DOLLARS ($3,504,060.00) ($292,005.00 per month) and
the phrase "the fifth (5th) anniversary of the Commencement Date until the
expiration of the term" shall be

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deemed deleted therefrom and the phrase "January 1, 2005 through and including
December 31, 2009" shall be deemed substituted in lieu thereof.

                  (6) The following shall be inserted in Article 38 of the Lease
as Section 38(A)(1)(iii) as fixed rent for the 12th Premises:

            "(iii) THREE MILLION EIGHT HUNDRED FOUR THOUSAND FOUR HUNDRED EIGHT
            AND 00/100ths DOLLARS ($3,804,408.00) ($317,034.00 per month) for
            the period from January 1, 2010 and continuing thereafter throughout
            the remainder of the term of this lease."

            (B) Article 42

                  The Base Tax Year set forth in Section 42(A)(iv) of the Lease
for the 16th Premises shall be the fiscal year July 1, 1999 to June 30, 2000.

            (C) Article 43

                  (1) The Expense Base Year set forth in Section 43(A)(5) of the
Lease for the 16th Premises shall be the calendar year 1999.

                  (2) The date "January 1, 1999" set forth in Section 43(B) of
the Lease for the 16th Premises shall be "January 1, 2000".

(D) Exhibit D

                  (1) The amounts "$28.75" and "$31.75" in Exhibit D with
respect to the 16th Premises shall be changed to "$32.00" and "$35.00",
respectively, the phrases "the day immediately preceding 5th anniversary of Rent
Commencement Date", "5th anniversary of Rent Commencement Date" and "the
expiration of initial term" shall be deemed changed to "December 31, 20'04",
"January 1, 2005" and "December 31, 2009", respectively.

                  (2) The amounts "$31.50" and "$34.00" in Exhibit D with
respect to the 12th Premises shall be changed to "$32.00" and "$35.00",
respectively, the phrases "the day immediately preceding 5th anniversary of
Commencement Date", "5th anniversary of

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Commencement Date" and "the expiration of initial term" shall be deemed changed
to "December 31, 2004", "January 1, 2005" and "December 31, 2009", respectively.

                  (3) The following shall be added to Exhibit D with respect to
the Existing Premises:

            "January 1, 2010 to the expiration of the initial term shall be
            $38.00 per rentable square foot."

            FOURTH: As same is applicable only to the Additional Premises,
effective upon the Commencement Date and continuing through the Expiration Date,
the Lease shall be deemed modified as follows:

            (A) Rule and Regulation #3

            Reference to loading bay #21 and freight elevator # F-8 in Insert 44
of the Text to Numbered Insertions shall be deemed a reference to loading bay
#22 and freight elevator # F-7.

            (B) Section 38 (A)(1)

                  (1) The amount of fixed rent for the Unit A Premises shall be
ONE MILLION SIX HUNDRED SIXTY-TWO THOUSAND SIX HUNDRED EIGHTY-EIGHT AND
00/100ths DOLLARS ($1,662,688.00) ($138,557.33 per month) from the Commencement
Date through and including December 31, 2004.

                  (2) The amount of fixed rent for the Unit B Premises shall be
SIX HUNDRED THIRTY-NINE THOUSAND SIX HUNDRED FORTY-EIGHT AND 00/100ths DOLLARS
($639,648.00) ($53,304.00 per month) from the Unit B Commencement Date through
and including December 31, 2004.

                  (3) The amount of fixed rent for the Unit C Premises shall be
ONE MILLION FORTY-THREE THOUSAND SIX HUNDRED FORTY-EIGHT AND 00/100ths

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DOLLARS ($1,043,648.00) ($86,970.67 per month) from the Unit C Commencement Date
through and including December 31, 2004.

                  (4) The amount of fixed rent for the 15th Premises shall be
THREE MILLION THREE HUNDRED FORTY-FIVE THOUSAND NINE HUNDRED EIGHTY-FOUR AND
00/100ths DOLLARS ($3,345,984.00) ($278,832.00 per month) (hereinafter referred
to as the "Initial 15th Rent") plus an amount equal to the product of (i) the
Initial 15th Rent and (ii) the percentage, if any, by which the "Price Index"
(as hereafter defined) on the 15th Premises Commencement Date exceeds the "Base
Price Index" (as hereafter defined) from the 15th Premises Commencement Date
through and including December 31, 2004.

                  (5) The amount of fixed rent for the 14th Premises shall be
THREE MILLION SIX HUNDRED FIFTY-NINE THOUSAND SIX HUNDRED SEVENTY AND 00/100ths
DOLLARS ($3,659,670.00) ($304,972.50 per month) from January 1, 2005 through and
including December 31, 2009.

                  (6) The amount of fixed rent for the 15th Premises shall be
THREE MILLION SIX HUNDRED FIFTY-NINE THOUSAND SIX HUNDRED SEVENTY AND 00/100ths
DOLLARS ($3,659,670.00) ($304,972.50 per month) (hereinafter referred to as the
"Second 15th Rent") plus an amount equal to the product of (i) the Second 15th
Rent and (ii) the percentage, if any, by which the Price Index on January 1,
2005 exceeds the Base Price Index from January 1, 2005 through and including
December 31, 2009.

                  (7) The following shall be inserted in Article 38 of the Lease
as Section 38(A)(1)(iii) as fixed rent for the 14th Premises:

            "(iii) THREE MILLION NINE HUNDRED SEVENTY-THREE THOUSAND THREE
            HUNDRED FIFTY-SIX AND 00/100ths DOLLARS ($3,973,356.00) ($331,113.00
            per month) for the

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            period from January 1, 2010 and continuing thereafter throughout the
            remainder of the term of the lease."

                  (8) The following shall be inserted in Article 38 of the Lease
as Section 38(A)(1)(iii) as fixed rent for the 15th Premises:

            "(iii) THREE MILLION NINE HUNDRED SEVENTY-THREE THOUSAND THREE
            HUNDRED FIFTY-SIX AND 00/100ths DOLLARS ($3,973,356.00) ($331,113.00
            per month) (hereinafter referred to as the "Third 15" Rent") plus an
            amount equal to the product of (x) the Third 15th Rent and (y) the
            percentage, if any, by which the Price Index on January 1, 2010
            exceeds the Base Price Index for the period from January 1, 2010 and
            continuing thereafter throughout the remainder of the term of the
            lease."

            (C) Section 38(A)(2)

            (1) For purposes of making certain determinations as to the fixed
rent payable for the 15" Premises, the following terms shall have the follow
meanings:

                  (i) "PRICE INDEX" shall mean the Consumer Price Index for All
Urban Consumers published by the Bureau of Labor Statistics of the United States
Department of Labor, New York, N.Y.-Northeastern NJ Area, All Items
(1982-84=100), or any successor index thereto, appropriately adjusted. In the
event that the Consumer Price Index is converted to a different standard
reference base or otherwise revised, the determination of adjustments provided
for herein shall be made with the use of such conversion factor, formula or
table for converting the Consumer Price Index as may be published by the Bureau
of Labor Statistics or, if said Bureau shall not publish same, then with the use
of such conversion factor, formula or table as may be published by
Prentice-Hall, Inc., or any other nationally recognized publisher of similar
statistical information. If the Consumer Price Index ceases to be published, and
there is no successor thereto, such other index as Landlord and Tenant shall in
good faith agree upon in writing shall be substituted for the Consumer Price
Index. If Landlord and Tenant are unable to agree as to such substituted index,
such matter shall be submitted to the American Arbitration

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Association or any successor organization for determination in accordance with
the regulations and procedures thereof then obtaining for commercial
arbitration.

                  (ii) "BASE PRICE INDEX" shall mean the Price Index in effect
on the date of this Second Amendment.

            (2) Promptly after the Price Indexes for the 15th Premises
Commencement Date, January 1, 2005 and January l, 2010, respectively, are
established, Landlord shall send a written notice to Tenant setting forth: (i)
the Price Index in effect on each of such dates; (ii) the Base Price Index;
(iii) the percentage, if any, by which the Price Index in effect on each such
respective date exceeds the Base Index; and (iv) the amount of fixed rent
payable with respect to the 15th Premises as provided in Article Fourth (B)(4),
(5) and (8) hereto. Each notice furnished under this Section (2) is hereinafter
called a "CPI NOTICE". Every CPI Notice given by Landlord shall be conclusive
and binding upon Tenant unless Tenant shall notify Landlord within thirty (30)
days after its receipt of such notice that it disputes the correctness of the
computations made thereon, specifying the particular respects in which such
computations are claimed to be incorrect. Pending the resolution of such dispute
by agreement or arbitration as aforesaid, Tenant shall, within thirty (30) days
after receipt of such disputed CPI Notice, pay fixed rent for the 15th Premises
due in accordance therewith, but such payment shall be without prejudice to
Tenant's position. If the dispute shall be resolved in Tenant's favor, Landlord
shall, within fifteen (15) days of such determination, pay Tenant the amount of
Tenant's overpayment of rents, if any, resulting from compliance with the
disputed CPI Notice.

                  (3) Notwithstanding anything contained in this Section (C) to
the contrary, in no event shall the fixed rent payable by Tenant with respect to
the 15th Premises be less than the numerically stated amount of fixed rent
payable by Tenant with respect to the 15th

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Premises pursuant to the provisions of Article Fourth (B)(4), (5) and (8) hereto
and, pending its receipt of a CPI Notice for any period for which such fixed
rent is due, Tenant shall continue to pay fixed rent with respect to the 15th
Premises in an amount equal to the numerically stated amount of fixed rent
payable for the period in question and, if any additional amount is due to
Landlord, Tenant shall pay such additional amount with the next installment of
fixed rent due under the Lease, as hereby amended.

                  (4) Landlord's failure to prepare and deliver the CPI notice,
or Landlord's failure to make a demand, shall not in any way cause Landlord to
forfeit or surrender any rights to collect any of the increases in fixed rent
that may have become due during the term of the Lease, as hereby amended.

            (D) Section 38(E)

            Notwithstanding anything contained herein or in the Lease to the
contrary and with respect only to the Additional Premises and the fixed rent due
with respect thereto, provided that no monetary default or no non-monetary
material default on the part of Tenant shall have occurred and be continuing
during the periods for which the following credits are to be applied (provided
further that Tenant shall be entitled to be reimbursed by Landlord for any fixed
rent or additional rent paid by Tenant during such periods for which Tenant
would otherwise have been entitled to receive such credit upon Tenant's cure of
such monetary default or such non-monetary material default), Tenant shall have
no obligation to pay (1) with respect to the Unit A Premises, fixed rent for the
period from the Commencement Date through and including the day next preceding
the first (1st) anniversary of the Commencement Date, (2) with respect to the
Unit B Premises, fixed rent for the period beginning on the Unit B Commencement
Date and which ends on the later of (a) eight (8) months from the Unit B
Commencement Date or (b) December 1,

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2000, (3) with respect to the Unit C Premises, the first eight (8) full monthly
installments of fixed rent from the Unit C Commencement Date, and (4) with
respect to the 15th Premises, the first twelve (12) full monthly installments of
fixed rent from the 15th Premises Commencement Date.

            (E) Section 39(E)

                  (1) The phrase "as a credit against Landlord's Work
Contribution (as hereafter defined)" shall be deemed deleted therefrom and the
phrase "at Tenant's sole cost and expense" shall be deemed substituted in lieu
thereof.

                  (2) The amounts "$50,361.00", "$125,902.50" and "$25,180.50"
and the phrase "the 12e day" as set forth in Section 39(E) of the Lease with
respect to the 16th floor, shall be modified with respect to the Additional
Premises only as follows:

                        (i) On the Commencement Date, "$51,959.00",
"$129,897.50", "$25,979.50", and "the 90th day", respectively.

                        (ii) On the Unit B Commencement Date, "$19,989.00",
"$49,972.50", "$9,994.50", and "the 90th day", respectively.

                        (iii) On the Unit C Commencement Date, "$32,614.00",
"$81,535.00", "$16,307.00", and "the Unit C Commencement Date", respectively.

                        (iv) On the 15th Premises Commencement Date,
"$104,562.00", "$261,405.00", "$52,281.00", and "the 15th Premises Commencement
Date", respectively.

            (F) Article 41

            Tenant agrees to accept possession of the Unit A Premises, the Unit
B Premises, the Unit C Premises, and the 15th Premises in their "as is"
condition on the respective

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commencement dates for each of the Unit A Premises, the Unit B Premises, the
Unit C Premises, and the 15th Premises and that Landlord shall have no
obligation to do any work in the Additional Premises, and that Tenant shall
perform any work required by it in the Additional Premises, at its sole cost and
expense (subject to the provisions of Article Fourth Section l(1) hereof) in
accordance with the applicable, provisions of the Lease, as hereby amended.

            (G) Article 42

            "Tenant's Proportionate Tax Share" as set forth in Section
42(A)(iii) of the Lease for the Additional Premises shall be as follows:

                  (1)   The Unit A Premises - 3.698%.

                  (2)   The Unit B Premises -1.416%.

                  (3)   The Unit C Premises - 2.321%.

                  (4)   The 15th Premises - 7.435%.

            (H) Article 43

            "Tenant's Proportionate Operating Share" as set forth in Section
43(A)(6) of the Lease for the Additional Premises shall be as follows:

                                    (1)    The Unit A Premises - 3.698%.

                                    (2)    The Unit B Premises -1.416%.

                                    (3)    The Unit C Premises - 2.321%.

                                    (4)    The 15" Premises - 7.435%.

            (I) Articles 44 and 45

                  (1) With respect only to the 14th Premises, the term
"Landlord's Work Contribution" as set forth in Section 44(A)(1) of the Lease
shall be $4,923,434.00 and a portion of Landlord's Work Contribution, not to
exceed $738,515.10, may be applied toward "soft costs"

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of architect's fees, engineering fees, space planning fees and filing fees and
other typical "soft Notwithstanding anything herein to the contrary, Tenant may
utilize the entire costs." Landlord's Work Contribution described herein whether
or not Landlord has delivered the Unit B Premises and/or the Unit C Premises,
and same may be utilized by Tenant entirely with respect to any one of the Unit
A Premises, Unit B Premises, or Unit C Premises, or in such proportion over any
of the Unit A Premises, Unit B Premises and/or Unit C Premises as Tenant may
elect in its sole discretion.

            (2) (i) (i) For purposes hereof, the term "Hazardous Materials"
shall mean asbestos and asbestos-containing materials and other materials,
which, as of the date hereof with respect to the Unit A Premises and as of the
date of each of the Unit B Premises Commencement Date with respect to the Unit B
Premises and the Unit C Commencement Date with respect to the Unit C Premises,
in accordance with applicable laws and rules of any governmental agencies having
jurisdiction, must be removed or otherwise abated. Landlord and Tenant hereby
acknowledge that, with respect to the 14 `" Premises, Landlord's Work
Contribution includes $51,959.00 with respect to the Unit A Premises, $19,989.00
with respect to the Unit B Premises and $32,614.00 with respect to the Unit C
Premises for the removal and/or abatement of Hazardous Materials. After Tenant
has completed the removal and/or abatement of Hazardous Materials in the Unit A
Premises, Unit B Premises and Unit C Premises, Tenant shall send to Landlord a
copy of receipted invoices therefor accompanied by an ACP-5 and other supporting
environmental reports required by all laws, rules and regulations of any
governmental agency, Building Department, and/or any other entity having
jurisdiction with respect thereto evidencing that such Hazardous Materials have
been removed and/or abated. Landlord shall cooperate with Tenant, at Tenant's
expense, in obtaining such evidence by

<PAGE>

promptly executing any documents in connection therewith required to be executed
by Landlord. In the event that the cost of such removal or abatement of any
Hazardous Materials exceeds $51,959.00 with respect to the Unit A Premises,
exceeds $19,989.00 with respect to the Unit B Premises or exceeds $32,614.00
with respect to the Unit C Premises, Landlord, within thirty (30) days of
receipt of such bill by Landlord and subject to the further provisions of this
subparagraph (2), shall pay any such excess amounts to Tenant. In the event
Landlord fails to pay any such excess amounts to Tenant within thirty (30) days
of Landlord's receipt of such bill, Tenant may offset such excess amounts not
paid by Landlord against the fixed rent and additional rent next becoming due
under the Lease, as hereby amended. In the event such costs to Tenant are less
than $51,959.00 with respect to the Unit A Premises, less than $19,989.00 with
respect to the Unit B Premises or less than $32,614.00 with respect to the Unit
C Premises, Tenant, within thirty (30) days after receipt of such bill by
Landlord and subject to the further provisions of this subparagraph (2), shall
pay to Landlord the difference between such amounts and the actual cost to
Tenant for such removal or abatement.

                        (ii) In the event that either Landlord or Tenant dispute
any amounts due to the other pursuant to subsection (i) above, then either party
may request that such dispute be submitted to arbitration. The party requesting
arbitration shall do so by giving notice to that effect to the other party, and
both parties shall promptly thereafter jointly apply to the American Arbitration
Association (or any organization successor thereto) in the City and County of
New York for the appointment of a single arbitrator.

                        (iii) The arbitration shall be conducted in accordance
with the then prevailing rules of the American Arbitration Association (or any
organization successor thereto) in the City and County of New York. In rendering
such decision and award, the

<PAGE>

arbitrator shall not add to, subtract from or otherwise modify the provisions of
this Agreement or the Lease.

                        (iv) If for any reason whatsoever a written decision and
award of the arbitrator shall not be rendered within ninety (90) days after the
appointment of such arbitrator, then at any time thereafter before such decision
and award shall have been rendered either party may apply to the Supreme Court
of the State of New York or to any other court having jurisdiction and
exercising the functions similar to those now exercised by such court, by
action, proceeding or otherwise (but not by a new arbitration proceeding) as may
be proper to determine the question in dispute consistently with the provisions
of this Agreement or the Lease.

                        (v) All the expenses of the arbitration shall be borne
by the parties equally except that each party shall be responsible for the
payment of its own legal fees and disbursements and expert witness fees.

                  (3) With respect only to the 15th Premises, the term
"Landlord's Work Contribution" as set forth in Section 44(A)(1) of the Lease
shall be $4,923,434.00 and a portion of Landlord's Work Contribution, not to
exceed $738,515.10, may be applied toward "soft costs" of architect's fees,
engineering fees, space planning fees and filing fees and other typical "soft
costs". Landlord and Tenant hereby acknowledge that, with respect to the 15t'
Premises, Landlord's Work Contribution includes $104,562.00 for the removal
and/or abatement of Hazardous Materials. After Tenant has completed the removal
and/or abatement of Hazardous Materials in the 15" Premises, Tenant shall send
to Landlord a copy of receipted invoices therefor accompanied by an ACP-5 and
other supporting environmental reports required by all laws, rules and
regulations of any governmental agency, Building Department, and/or any other

<PAGE>

entity having jurisdiction with respect thereto evidencing that such Hazardous
Materials have been removed and/or abated. Landlord shall cooperate with Tenant,
at Tenant's expense, in obtaining such evidence by promptly executing any
documents in connection therewith required to be executed by Landlord. In the
event that the cost of such removal or abatement exceeds $104,562.00, Landlord,
within thirty (30) days of receipt of such bill by Landlord and subject to the
further provisions of this subparagraph (3), shall pay any such excess amounts
to Tenant. In the event that Landlord fails to pay any such excess amounts to
Tenant within thirty (30) days of Landlord's receipt of such bill, Tenant may
offset such excess amounts not paid by Landlord against the fixed rent and
additional rent next becoming due under the Lease, as hereby amended. In the
event such costs to Tenant are less than $104,562.00, Tenant, within thirty (30)
days after receipt of such bill by Landlord and subject to the further
provisions of this subparagraph (3), shall pay to Landlord the difference
between such amounts and the actual cost to Tenant for such removal or
abatement. In the event that either Landlord or Tenant dispute any such amounts
due to the other pursuant to this subparagraph (3), such dispute shall be
determined in accordance with the provisions of Article Fourth Section I (2)
hereof, with any references to the "Unit A Premises", the "Unit B Premises" or
the "Unit C Premises" therein being deemed to refer to the 15th Premises.

                  (4) Subdivisions (a) - (f) of Section 44(A)(2) of the Lease
with respect to the Additional Premises shall be deleted therefrom.

                  (5) The last paragraph of Section 45(A) of the Lease is
amended for the Additional Premises to change the amount "$100,000" to the
amount "$200,000".

<PAGE>

            (J) Section 56(J)(2)

            The percentage in Section 56(J)(2) of the Lease with respect to the
Additional Premises shall be 14.87%, provided that Tenant does not elect to
exercise Tenant's Termination Option (as hereafter defined). In the event Tenant
does elect to exercise Tenant's Termination Option then the percentage in
Section 56(J)(2) of the Lease with respect to the Additional Premises shall be
7.435%.

            (K) Section 58(A)(i):

            With respect only to the 15th Premises, within fifteen (15) days
from the date that Landlord has given notice to Tenant that broom-clean
possession of the 15th Premises is available to Tenant, in addition to any other
security being held by Landlord, Tenant shall deliver to Landlord a Letter of
Credit in accordance with, and meeting the requirements of, the provisions of
Article 58 of the Lease in the amount of THREE MILLION AND 00/100 DOLLARS
($3,000,000.00) which Letter of Credit will be held by Landlord in accordance
with the provisions of Article 58 and as same may be reduced in accordance with
the provisions of Article 58 of the Lease.

            (L) Exhibit D

            The amounts "$28.75" and "$31.75" in Exhibit D shall be changed to
"$32.00" and "$35.00", respectively, the phrases "the day immediately preceding
5th anniversary of Rent Commencement Date", "5th anniversary of Rent
Commencement Date" and "the expiration of initial term" shall be deemed changed
to "December 31, 2004", "January 1, 2005" and "December 31, 2009", respectively,
and the following shall be added:

            "January 1, 2010 to the expiration of the initial term shall be
            $38.00 per rentable square foot."

<PAGE>

            FIFTH: Provided that no monetary default or no non-monetary material
default on the part of Tenant shall have occurred and be continuing on the date
Tenant sends "Tenant's Termination Notice" (as hereafter defined), which default
is continuing after any required notice and the expiration of any applicable
cure period, Tenant shall have the option (hereinafter referred to as "TENANT'S
TERMINATION OPTION") to terminate the Lease as to the 15th Premises only,
effective upon Landlord's receipt of Tenant's Termination Notice (the date of
such receipt of said notice being hereinafter referred to as the "CANCELLATION
DATE"), upon the following terms and conditions:

                  (1) If Tenant elects to exercise Tenant's Termination Option,
Tenant shall send written notice thereof (hereinafter referred to as "TENANT'S
TERMINATION NOTICE") to Landlord by registered or certified mail, return receipt
requested, or by nationally recognized overnight courier providing for receipted
delivery, on or before December 31, 2000, accompanied by a bank, cashiers' or
certified check to the order of Landlord in the amount of $250,000.00
(hereinafter referred to as the "CANCELLATION FEE");

                  (2) In the event Tenant exercises Tenant's Termination Option
and pays the Cancellation Fee in the manner and within the time period set forth
above, the Lease shall thereupon terminate (as to the 15th Premises only) on the
Cancellation Date as though the Cancellation Date was the date initially set
forth as the Expiration Date of the Lease with respect to the 15th Premises only
and the parties hereto shall have no further obligations to the other under the
Lease, as hereby amended, with respect only to the 15th Premises.

                  (3) If Tenant fails to exercise Tenant's Termination Option in
the manner (including, without limitation, the payment of the Cancellation Fee)
and within the time period set forth above, the Termination Option shall be
deemed null and void and Tenant shall

<PAGE>

have no further option to cancel the Lease as to the 15 `h Premises pursuant to
the provisions set forth above.

            SIXTH: The following shall be added to Article 39 of the Lease as
Sections 39(H)-(M):

                  (H) Tenant has advised Landlord that it may require one or
            more back-up generator(s) to provide electricity to certain of
            Tenant's equipment in the Additional Premises and the Existing
            Premises in the event of the interruption of electrical service to
            the Additional Premises and the Existing Premises. Such back-up
            generator(s) would necessitate the construction, installation,
            operation, testing, maintenance and use by Tenant of a generator(s),
            together with a fuel oil storage tank (hereinafter referred to as
            the "FUEL TANK") and related equipment (including Tenant's transfer
            switch), mountings, supports and risers (herein collectively
            referred to as the "GENERATOR(S)"). Subject to the further
            provisions of this Article 39, upon the request of Tenant, Landlord
            shall make available to Tenant on the Unit B Commencement Date, at
            no cost to Tenant, for Tenant's own use (and not for resale or
            sublicensing purposes) (i) up to 450 square feet of usable space
            (hereinafter referred to as the "GENERATOR AREA") on the portion of
            the southwest second (2nd) floor roof set-back.. area of the
            Building, as designated by Landlord, in its sole discretion (which
            space designated shall be feasible for such generator(s)
            installation), the approximate location of which shall be on a
            portion of the area cross-hatched on the floor plan annexed hereto
            as Exhibit E-l, for the Generator(s), (ii) up to 200 square feet of
            usable space or such greater amount as is necessary to hold a 5,000
            gallon conventional fuel tank (hereinafter referred to as the "TANK
            AREA") in the basement of the Building, the approximate location of
            which is as cross-hatched on the floor plan annexed hereto as
            Exhibit E-2, for the Fuel Tank used in connection with the
            Generator(s), and (iii) up to 50 square feet of usable space
            (hereinafter referred to as the "SWITCH AREA") in the basement of
            the Building at a location to be determined and mutually agreed upon
            by Landlord and Tenant for the installation and placement of
            Tenant's transfer switch used in connection with the Generator(s).
            The foregoing locations will permit the connection of such
            Generator(s) to the Additional Premises and the Existing Premises in
            a reasonable manner. Tenant's use of the Generator Area, the Tank
            Area and the Switch Area of the Building shall be on an exclusive
            basis. Notwithstanding anything contained herein to the contrary,
            within fifteen (15) days after the delivery of the Unit C

<PAGE>

            Premises to Tenant, Tenant shall notify Landlord in writing whether
            Tenant will use each of the Generator Area, the Tank Area and the
            Switch Area. In the event Tenant fails to so notify Landlord,
            Tenant's right to use each of the Generator Area, the Tank Area and
            the Switch Area shall thereafter be on a "first-come, first-served"
            basis subject to availability. In connection with Tenant's use of
            each of the Generator Area, the Tank Area and the Switch Area of the
            Building, Tenant shall have access as reasonably required to each of
            the Generator Area, the Tank Area and the Switch Area for the
            construction, installation, maintenance, repair, operation and use
            of the Generator(s), the Fuel Tank and Tenant's transfer switch.
            Tenant shall, at its sole cost and expense, be permitted to fence-in
            or enclose each of the Generator Area, the Tank Area and the Switch
            Area in a manner reasonably acceptable to Landlord and in compliance
            with applicable law, but Tenant shall provide Landlord with a key
            for such enclosure. It is agreed, however, that only Tenant and
            authorized licensed electrical engineers and electrical contractors
            approved in advance by Landlord (which approval shall not be
            unreasonably withheld or delayed), federal, state or local
            governmental inspectors or persons under their direct supervision
            will be permitted to have access to each of the Generator Area, the
            Tank Area and the Switch Area. Tenant further agrees to exercise
            firm control over the people requiring access to each of the
            Generator Area, the Tank Area and the Switch Area in order to keep
            to a minimum the number of people having access to each of the
            Generator Area, the Tank Area and the Switch Area and the frequency
            of their visits. Landlord shall, at no cost to Tenant, provide
            reasonably sufficient space in the shafts of the Building, the
            approximate location of which shall be reasonably acceptable to
            Landlord and Tenant, to allow Tenant, at Tenant's sole cost and
            expense, to run electrical wiring from the Generator(s) to the
            Additional Premises and to the Existing Premises and from the
            Building generator described in Paragraph 39G of the Lease to the
            Generator(s) and to run fuel lines from the Fuel Tank to the
            Generator(s). The installation of the Generator(s) shall constitute
            a Tenant's Change and shall be performed at Tenant's sole cost and
            expense in accordance with, and subject to, the provisions of this
            lease, including, without limitation, Article 45 hereof, and
            notwithstanding anything herein or in this lease to the contrary,
            Tenant's right to install the Generator(s) shall be subject to the
            prior approval by Landlord of plans and specifications for the
            Generator(s) and the manner in which same is attached to the
            Generator Area, which approval shall not be unreasonably withheld,
            conditioned or delayed. All of the applicable provisions of this
            lease shall apply to the installation, use, operation and
            maintenance of the Generator(s), including,

<PAGE>

            without limitation, provisions relating to compliance with laws,
            insurance, indemnity, hazardous material, repairs and maintenance.
            The license granted to Tenant in this Article 39 shall not be
            assignable by Tenant separate and apart from this lease and may not
            be sublicensed by Tenant. Notwithstanding anything in Article 39 of
            this lease to the contrary, if Tenant installs the Generator(s),
            Tenant may disconnect from, at its sole cost and expense, and
            terminate its use of, the Building generator without further
            obligation to Landlord with respect thereto.

                  (I) Tenant shall install, maintain, operate, repair and use
            the Generator(s), all at its sole cost and expense, and in such a
            manner so as not to cause any unreasonable interference to other
            tenants, occupants, licensees or Landlord in the Building or damage
            to or interference with the operation of the Building or any
            Building systems.

                  (J) Landlord may, at its option, at any time during the term
            of this lease, after reasonable prior notice to Tenant (except in
            the event of an emergency when no notice shall be required) relocate
            the Generator(s) to another area of the .second (2nd) floor roof
            set-back area designated by Landlord and relocate the Fuel Tank and
            Tenant's transfer switch to another area of the basement designated
            by Landlord, provided that such relocation does not cause the
            back-up electrical service to be interrupted or impaired and such
            relocation shall be performed at Landlord's sole cost and expense.

                  (K) (1) Landlord shall not have any obligations with respect
            to the Generator(s) or compliance with any laws or requirements of
            public authorities relating thereto (including, without limitation,
            the obtaining of any required permits or licenses, or the
            maintenance thereof), nor shall Landlord be responsible for any
            damage that may be caused to Tenant or the Generator(s) by any other
            tenant or occupant of the Building. Landlord makes no
            representa-tion with respect to the Generator(s) or its capacity or
            ability to provide back-up electrical service and Tenant agrees that
            Landlord shall not be liable to Tenant therefor.

                       (2) Any electrical service required for Tenant's use of
            the Generator(s) shall be paid for by Tenant pursuant to the
            provisions of Article 39 of this lease.

                       (3) Tenant shall (i) be solely responsible for any
            damage caused to Landlord or any other entity, person or property as
            a result of the installation, maintenance or use of the
            Generator(s), (ii) promptly pay any tax, license, permit or other

<PAGE>

            fees or charges imposed pursuant to any laws and/or requirements of
            public authorities relating to the installation, maintenance or use
            of the Generator(s), (iii) promptly comply with all reasonable
            precautions and safeguards recommended by Landlord's insurance
            company and all federal, state or municipal governmental authorities
            or agencies, and (iv), at its sole cost and expense, (x) perform all
            necessary repairs or replacements to, or maintenance of, the
            Generator(s), (y) promptly repair any and all damage to each of the
            Generator Area, the Tank Area and the Switch Area and to any other
            part of the Building caused by or resulting from the installation,
            maintenance, repair, operation or removal of the Generator(s) or any
            portion thereof, and (z) at Tenant's Option, except as otherwise
            provided in Section (M) below, terminate its use of the Generator(s)
            and disconnect and remove same.

                  (L) Tenant shall have the right, for the period from the
            Commencement Date through six (6) months after the date Landlord
            delivers the Generator Area to Tenant, upon prior written notice to
            Landlord, to connect to the Building generator to allow Tenant to
            receive up to 350 K.W. of emergency electricity service (in addition
            to that provided to Tenant under Paragraph 39G of the Lease) from
            the Building generator at no cost to Tenant, except that Tenant
            shall be responsible for the cost of connecting to, and
            disconnecting from (at the end of such period), the Building
            generator. In the event Tenant does connect to the Building
            generator as aforesaid, Landlord agrees to, on a monthly basis,
            exercise the Building generator, check and maintain all fluid and
            battery levels and maintain a maintenance log of all maintenance
            performed to the Building generator. Landlord further agrees to
            maintain a contract with a generator service company to visually
            inspect and perform preventive maintenance two (2) times per year.
            Landlord shall, upon two (2) weeks prior written notice by Tenant
            and at Tenant's sole cost and expense, assist Tenant in scheduling
            an emergency power test (a/k/a pull the plug test). Such test shall
            be limited to the period for which Tenant is connected to the
            Building generator and Landlord shall not be obligated to conduct
            such test more than two (2) times a year.

                  (M) Tenant acknowledges and agrees that the privileges granted
            Tenant under Sections (H) - (M) shall merely constitute a license
            and shall not, now or at any time after the installation of the
            Generator(s), be deemed to grant Tenant a leasehold or other real
            property interest in the Building or any portion thereof. The
            license granted to Tenant in Sections (H) - (M) shall automatically
            terminate and expire upon the expiration or earlier termination of
            this lease and the termination of such license shall be
            self-operative and no further instrument shall be required to effect
            such

<PAGE>

            termination and Tenant shall, at its sole cost and expense, unless,
            upon written request given by Tenant at least six (6) months prior
            to the Expiration Date requesting that the Generator(s) remain on
            the Generator Area, the Fuel Tank remain on the Tank Area and
            Tenant's transfer switch remain on the Switch Area, and such request
            is thereafter consented to by Landlord, remove the Generator(s) from
            the Generator Area, the Fuel Tank from the Tank Area and Tenant's
            transfer switch from the Switch Area within three (3) months after
            the expiration or earlier termination of this lease and repair any
            damage to each of the Generator Area, the Tank Area, the Switch Area
            and the Building resulting from such removal so as to place same, as
            closely as possible, in the same condition as existed prior to the
            installation of the Generator(s), the Fuel Tank and Tenant's
            transfer $witch, normal wear and tear excepted. This obligation
            shall survive the expiration or sooner termination of this lease.
            The foregoing notwithstanding, upon request by Landlord, Tenant, at
            Tenant's sole cost and expense, promptly shall execute and deliver
            to Landlord, in recordable form, any certificate or other document
            confirming the termination of Tenant's right to use the Generator
            Area, the Tank Area and the Switch Area.

            SEVENTH: Article 52 of the Lease shall apply to both the Existing
Premises and the Additional Premises together. In connection therewith, Landlord
and Tenant confirm that any calculation concerning rental terms of all or any
portion of the Existing Premises shall be performed using the rental terms of
the Existing Premises set forth in this Amendment, and any calculation
concerning rental terms of all or any portion of the Additional Premises shall
be performed using the rental terms of the Additional Premises set forth in this
Agreement.

            Further, the following is added to Article 52 of the Lease as
            Section 52(K):


            "(K) Tenant may sublease (a) the 14th Premises or any part thereof
            for terms not to exceed the day immediately preceding the third
            (3`d) anniversary of the Commencement Date provided that there shall
            not be more than four (4) entities (including Tenant) occupying the
            14th Premises, and (b) the 15th Premises or any part thereof for
            terms not to exceed the day being immediately preceeding the third
            (3`d) anniversary of the 15th Premises Commencement Date provided
            there shall not be more than four (4) entities (including Tenant)
            occupying the 15th Premises, pursuant, and subject, to all the other
            terms and conditions of this Article 52 (upon notice to Landlord,
            but without the need for

<PAGE>

            Landlord's consent thereto, subject to the other terms and
            conditions of this Article 52), except that Sections 52(F), 52(G),
            52(H) and 52(I) shall not apply with respect to any such sublease."

            EIGHTH: Section 56J(1) of the Lease shall apply to both the Existing
Premises and the Additional Premises together. In connection therewith, Section
56(J)(1) of the Lease shall be deleted therefrom and the following shall be
substituted in lieu hereof:

            "(1) Landlord shall supply condenser water free of charge during
            "REGULAR HOURS" (7:00 a.m. - 6:00 p.m.) of "BUSINESS DAYS" (which
            term is used herein to mean all days except Saturdays, Sundays and
            days (hereinafter referred to "HOLIDAYS") observed by the Federal or
            New York State government as legal holidays or the building service
            employees' union holidays) throughout the year and at the rate of
            $50.00 per hour during "OVERTIME HOURS" (6:00 p.m. - 7:00 a.m.) for
            up to 1200 tons to serve the Existing Premises and the Additional
            Premises together. Landlord shall also make available to Tenant
            during the term of this lease supplemental condenser water to serve
            the Existing Premises and the Additional Premises for up to thirty
            (30) tons (i.e., two (2) 15 ton units) during regular hours and
            overtime hours free of charge on business days and for all hours on
            holidays. With respect to any condenser water required to supply any
            air-conditioning which Tenant may be permitted to install in excess
            of 1230 tons (which excess shall include Tenant's use of condenser;
            water for ug to an additional 400 tons of capacity necessary for the
            15 Premises), Landlord shall make available to Tenant, and Tenant
            shall pay for, as additional rent, such additional condenser water
            at the rate of $.072 per ton per hour during regular hours and
            overtime hours of business days and for all hours on holidays
            provided, however, that notwithstanding anything in the foregoing to
            the contrary, there shall be no charge to Tenant for condenser water
            for up to an additional 400 tons of capacity for the 15t' - Premises
            during regular hours of business days.

            NINTH: (a) (a) Landlord hereby grants Tenant, at no cost to Tenant,
a license during the term of the Lease, as extended by this Agreement, on the
terms and conditions contained herein and in the Lease to install and maintain,
at Tenant's sole cost and expense, the name of Tenant in the lobby of the
Building on the wall in a location mutually satisfactory to Landlord and Tenant
(such name of Tenant is hereinafter referred to as the "LOBBY NAME

<PAGE>

SIGN") provided that Tenant's name shall be displayed in a similar size to that
of the name of the Daily News presently located in the lobby of the Building and
shall be made of similar materials and finishes as that of the Daily News' name
presently existing in the lobby of the Building. Tenant shall, at Tenant's sole
cost and expense, maintain the Lobby Name Sign in good order and condition,
reasonable wear and tear excepted. Within thirty (30) days after the Expiration
Date or sooner termination of the Lease, Tenant shall remove the Lobby Name Sign
and repair any damage to the lobby wall of the Building resulting from such
removal.

                  (b) Landlord hereby grants Tenant, at no cost to Tenant, a
license, during the term of the Lease, as extended by this Agreement, on the
terms and conditions contained herein and in the Lease, to install and maintain,
in good order and condition, reasonable wear and tear excepted, at Tenant's sole
cost and expense, the following: (i) on an exclusive basis, two (2) structural
signs (hereinafter referred to as the "ROOF SIGNS"), on the upper 16" floor roof
of the Building which location shall be from the southern most end to the
northern most end (between the existing columns) of the Building, facing east
and west, the height of such Roof Signs (including the structures supporting
same) shall not exceed a height of 32.5 feet as measured from the surface of the
upper 16th floor roof, provided that the Roof Signs shall in all events comply
with all requirements of Laws (as hereafter defined). Such Roof Signs shall
contain the name and/or logo and shall be in the corporate colors of Tenant, or
any corporation or entity which is controlled by Tenant ("CONTROL" being defined
as ownership of more than fifty(50%) percent of all of the voting stock of a
corporation or more than fifty (50%) percent of all the legal and equitable
interest in any other entity); (ii) the name of Tenant on the side of the
entryway of the Building, the location of which shall be reasonably acceptable
to Landlord and Tenant, and (iii) the name of Tenant on Tenant's items of
equipment, furniture,

<PAGE>

installations or personalty on the Roof/Set-Back Area provided that same cannot
be observed from the street level (such Roof Signs, the name of Tenant on the
side of the entryway of the Building and on the Roof/Set-Back Area are
hereinafter collectively referred to as the "OUTDOOR NAME SIGNS"), provided
that, except as otherwise expressly provided in this subparagraph (b), the
location, size, content, color, materials and finish of the Outdoor Name Signs
shall be previously approved by Landlord which approval shall not be
unreasonably withheld, delayed or conditioned. Tenant's right to install and
maintain the Roof Signs is expressly conditioned on, and subject to, Tenant, or
any corporation or entity which is controlled by Tenant, occupying at least
150,000 rentable square feet of office space in the Building for the purpose of
conducting its or their own business. In the event that, at any time, Tenant, or
any corporation or entity which is controlled by Tenant, is in occupancy of less
than 150,000 rentable square feet of office space in the Building, Tenant shall,
within three (3) months after such date, at its sole cost and expense, remove
the Roof Signs and repair any damage to the Building resulting from such
removal. Notwithstanding anything hereinabove to the contrary, Landlord hereby
approves, (x) except as to materials and finish, the plan annexed hereto as
Exhibit F for the Roof Signs and (y) the right of Tenant to maintain the Outdoor
Name Signs that contain the name, logo and corporate colors of Tenant, or any
corporation or entity which is controlled by Tenant. Tenant shall, prior to
installing such Outdoor Name Signs, at its sole cost and expense, procure and
thereafter maintain on a current basis, any governmental permits and licenses
from all authorities having jurisdiction, which may be required pursuant to any
present or future law, statute, ordinance, rule, regulation, other governmental
order or controlling judicial determination of any federal, state, local,
municipal or other governmental body, agency or authority having jurisdiction
and all departments, commissions, boards and officers thereof (hereinafter
referred to

<PAGE>

as "LAWS"), and shall at all times comply with all requirements of Laws, which
shall impose any obligation, order or duty upon Landlord or Tenant with respect
to or affecting the Outdoor Name Signs. Landlord shall cooperate with Tenant, at
Tenant's sole cost and expense, in obtaining such governmental permits and
licenses in connection with the Outdoor Name Signs. Landlord shall have no
obligation with respect to the Outdoor Name Signs. Within three (3) months after
the Expiration Date or sooner termination of the Lease, Tenant shall, at its
sole cost and expense, remove the Outdoor Name Signs and repair any damage to
the Building resulting from such removal. The rights granted to Tenant hereunder
shall not be sublet or sublicensed by Tenant and may not be assigned except in
connection with a permitted assignment of the Lease.

            TENTH: Article 53 of the Lease and Section 56(1) of the Lease are
hereby deleted in their entirety.

            ELEVENTH: Landlord acknowledges that Tenant, as part of its work to
prepare the 14th Premises for its use, will be tapping into the condenser water
outlet on the 14th Premises which is also utilized by the existing tenant of the
Unit B Premises and the Unit C Premises. Landlord represents that adequate
capacity for condenser water exists for the use of both Tenant and such existing
tenant so as to supply condensor water to Tenant in accordance with the
provisions of the Lease, as hereby amended. Notwithstanding anything hereinabove
or in this Agreement to the contrary, in the event Tenant is unable to tap into
the condenser water outlet on the 14th Premises while the existing tenant is
utilizing same, Tenant may, at its sole cost and expense, install, operate,
maintain and repair an air-cooled system for the period from the date Tenant is
unable to tap into the condenser water outlet through six (6) months after the
Unit C Premises Commencement Date. Such air-cooled system shall be vented to the
outside in a location, and such vent or louver shall be constructed utilizing a
material, reasonably acceptable

<PAGE>

to Landlord. Tenant shall be responsible, at it sole cost and expense, for
disconnecting and removing such air-cooled system and any vent or louver and
repairing and damages to the Building resulting therefrom.

            TWELFTH: (a) (a) Commencing on April 1, 2000 and continuing
thereafter during the term of the Lease, as hereby amended, Landlord, subject to
any present or future law or rule of any governmental agency having jurisdiction
and all applicable Building codes and rules and except during periods where
emergency or repair situations exist, will designate one passenger elevator cab
in the high rise elevator bank to service only the 12th, 14th, 15th (upon the
15th Premises Commencement Date and provided Tenant does not exercise Tenant's
Termination Option) and 16th floors and the lobby of the Building for the
exclusive use of Tenant and its visitors and invitees. Notwithstanding the
foregoing, such passenger elevator cab shall not service nor stop on the 15th
Premises until the 15th Premises Commencement Date, provided Tenant does not
exercise Tenant's Termination Option. All work necessary to reprogram or
otherwise prepare such elevator cab for such exclusive use including, without
limitation, increasing such use to service the 15th Premises (provided Tenant
does not exercise Tenant's Termination Option), shall be performed by Landlord,
and Tenant shall reimburse Landlord for the actual, reasonable, out-of-pocket
costs incurred by Landlord in connection therewith within thirty (30) days of
receipt of a bill thereafter accompanied by reasonable back-up information with
respect to such costs. Notwithstanding anything in the foregoing to the
contrary, Landlord shall obtain bids for all work necessary to reprogram or
otherwise prepare the aforesaid elevator cab for such exclusive use from not
less than three (3) elevator maintenance and repair companies of recognized
standing in the Borough of Manhattan, one of which may be selected by Tenant.
Landlord will allow Tenant to participate in the bidding process and Landlord
shall

<PAGE>

select the lowest qualified bidder to perform the aforesaid work unless Landlord
and Tenant otherwise mutually determine to select another bidder. During the
term of the Lease, Landlord shall maintain such elevator cab in the same manner
as it is obligated to maintain all other passenger elevators in the Building in
accordance with the provisions of the Lease, as hereby amended. Nothing herein
shall eliminate or reduce Landlord's obligation to maintain such elevator in
such good working order throughout the term of the Lease, as hereby extended by
this Agreement.

                  (b) As of April 1, 2000, Landlord hereby grants Tenant, at no
cost to Tenant, a license for the period from April 1, 2000 and continuing
thereafter throughout the term of the Lease, as extended by this Agreement, on
the terms and conditions contained herein and in the Lease to install and
maintain, at Tenant's sole cost and expense, a sign setting forth that such
dedicated passenger elevator is for Tenant's exclusive use. Such sign shall be
installed on the wall in the lobby of the Building adjacent to the dedicated
passenger elevator provided that the exact location of such sign and the size,
materials and finishes used for such sign shall be reasonably satisfactory to
Landlord. Tenant shall, at Tenant's sole cost and expense, maintain the sign in
good order and condition, reasonable wear and tear excepted. Within thirty (30)
days after the Expiration Date or sooner termination of the Lease, Tenant shall
remove the sign and repair any damage to the lobby wall of the Building
resulting from such removal.

                  (c) Commencing on the Unit C Commencement Date and continuing
thereafter during the term of the Lease, as hereby amended, Tenant shall be
entitled to utilize, on an exclusive basis and without additional cost except as
expressly set forth in this Article Twelfth, the presently decommissioned and
out-of-service elevator cab and elevator shaft in the north east quadrant of the
Building (hereinafter collectively referred to as the "F-4

<PAGE>

ELEVATOR") which presently exists between the 12`h floor and the 15" floor of
the Building upon the following terms and conditions:

            (1) Tenant understands that the F-4 Elevator is available for
Tenant's use in its present "as is" condition and acknowledges that same is
decommissioned and out-of-service and may not presently be used.

            (2) In the event Tenant elects to utilize the F-4 Elevator, Tenant
shall, at its sole cost and expense, recommission the F-4 Elevator by making all
necessary repairs and improvements thereto, at its sole cost and expense, which
repairs and improvements shall be made in accordance with all of the applicable
provisions of the Lease, as hereby amended, and in accordance with all laws,
rules and regulations of any governmental agency, Building Department, and/or
any other entity having jurisdiction with respect thereto. Landlord shall
cooperate, at Tenant's expense, by promptly executing any documents in
connection therewith required to be executed by Landlord. Prior to commencing
any such work or repairs, Tenant shall obtain and thereafter maintain during any
period during which it uses or does any work or any renovation with respect to
the F-4 Elevator, all permits, licenses or any other required approvals with
respect thereto.

            (3) In connection with the renovation, recommissioning and use of
the F-4 Elevator, provided Tenant does not exercise Tenant's Termination Option,
Tenant shall, upon the 15th Premises Commencement Date, be entitled to extend
same so as to run between the 12th floor and the 16th floor of the Building,
including, without limitation, cutting any slab between the 15th Premises and
the 16th floor of the Building. Any such extension shall be performed at the
sole cost and expense of Tenant, and shall thereafter be maintained and repaired
at Tenant's sole cost and expense and, in accordance with all applicable laws,
rules and

<PAGE>

regulations of any governmental agency, Building Department, and any other
entity having jurisdiction with respect thereto. Tenant shall not be required to
restore any slab opening between the 15th Premises and the 16th floor of the
Building on the Expiration Date or sooner termination of the Lease. Tenant
acknowledges that Landlord has made no representations that the F-4 Elevator may
be used for any purpose or that same may be recommissioned and Tenant is not
relying on any representation and that the inability of Tenant to use the F-4
Elevator or extend same to the 16th floor shall in no way affect the Lease, as
hereby amended, or Tenant's obligations thereunder. Tenant further acknowledges
that Landlord shall have no obligations of any kind with respect to the F-4
Elevator and all expenses with respect thereto and all repairs and maintenance
thereof shall be at the sole cost and expense of Tenant who shall have sole
responsibility therefor.

            THIRTEENTH: In the event the existing tenant of the Unit B Premises
and the Unit C Premises or its employees and agents (including its own security
guards) impedes Tenant's access by means of ingress and/or egress to each of the
Unit A Premises and the Unit B Premises as of the Unit B Premises Commencement
Date, Landlord shall, upon Tenant's request, take all action available to
Landlord at law or in equity against such existing tenant to prevent such
impediment from continuing but in no event shall Landlord be obligated to
terminate the lease(s) for such existing tenant.

            FOURTEENTH: Tenant warrants and represents that it has dealt with no
brokers other than Insignia/ESG, Inc. ("INSIGNIA") and Newmark & Company Real
Estate, Inc. ("NEWMARK") in connection with this Agreement. Tenant agrees to
indemnify, defend and hold Landlord harmless, including reasonable attorneys'
fees and expenses, against any claims for brokerage commission in connection
with this Agreement arising out of any conversations or

<PAGE>

negotiations had by Tenant with any broker other than Insignia and Newmark.
Landlord will pay the leasing commission due to Insignia and Newmark pursuant to
a separate agreement or agreements and will indemnify Tenant for all claims of
brokers which have dealt with Landlord in connection with this Agreement and not
dealt with Tenant.

            FIFTEENTH: All notices to Landlord shall be addressed to Landlord
c/o Max Capital Management Corp., 230 Park Avenue, 17`" Floor, New York, New
York 10169 with a copy to FischbeinoBadillooWagneroHarding, 909 Third Avenue,
New York, New York 10022, Attention: Barry E. Shimkin, Esq.

            SIXTEENTH: In the event Landlord objects to a specific aspect of any
plans and specifications submitted by Tenant to Landlord in connection with any
Alterations and/or Tenant's Changes (as defined in the Lease), such objection
shall be limited to such portion of the plans and specifications specifically
objected to by Landlord and those portions of the plans and specifications not
specifically objected to by Landlord shall be deemed approved.

            SEVENTEENTH: This Agreement may be executed in two or more
counterparts and shall be deemed to have become effective when and only when one
or more of such counterparts shall have been signed by or on behalf of each of
the parties hereto, although it shall not be necessary that any single
counterpart be signed by or on behalf of both of the parties hereto, and all
such counterparts shall be deemed to constitute but one and the same instrument.
A faxed signature by or on behalf of any party on any counterpart shall be
deemed to be the equivalent of the signature of such party, it being understood
that the counterpart containing such existing signature shall be promptly
thereafter forwarded to the other party hereto.

<PAGE>

            EIGHTEENTH: This Agreement may not be changed, modified or canceled
orally. As amended hereby, the Lease is hereby ratified and confirmed in all
respects and shall be binding upon the parties hereto and their respective
successors and assigns.

<PAGE>

      IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the day and year first above written.

                                450 WESTSIDE PARTNERS, LLC

                                By:  MAX AG 450, LLC

                                    By: MAX CAPITAL MANAGEMENT CORP., a Member

                                         By: /s/illegible
                                            ----------------------------------
                                               Name:
                                               Title:


                                DOUBLECLICK, INC.

                                By:  /s/ Dwight Merriman
                                   -------------------------------------------
                                   Name: Dwight Merriman
                                   Title: Chief Technology Officer