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                                                                    EXHIBIT 10.3

                               SECURITY AGREEMENT

This SECURITY AGREEMENT, dated as of October 4, 2001, is by and between ENGAGE,
INC., a Delaware corporation having its principal place of business at One
Hundred Brickstone Square, Andover, Massachusetts 01810 (the "Debtor"') and
CMGI, INC., a Delaware corporation having an address at One Hundred Brickstone
Square, Andover, Massachusetts 01810 (the "Lender").

                              W I T N E S S E T H:

WHEREAS, the Lender has advanced funds in the amount of $42,700,000 and
$8,000,000 to the Debtor and has agreed to advance funds in the form of
additional intercompany debt incurred by the Debtor (collectively, the "Loans"),
which Loans are evidenced by a Secured Convertible Demand Note dated as of
September 30, 2001 in the principal amount of $42,700,000, a Secured Convertible
Demand Note dated as of October 4, 2001 in the principal amount of $8,000,000
and a Secured Convertible Demand Note dated as of October 4, 2001 representing
any additional intercompany debt incurred by the Debtor (collectively, the
"Note"); and

WHEREAS, the willingness of the Lender to make the Loans is subject to the
condition, among others, that the Debtor shall execute and deliver this
Agreement and grant the security interest hereinafter described;

NOW THEREFORE, in consideration of the willingness of the Lender to make the
Loans to the Debtor, and for other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, it is hereby agreed, with the
intent to be legally bound, as follows:

1.       DEFINED TERMS. Except as otherwise expressly defined herein, all
capitalized terms shall have the meanings ascribed to them in the Notes.


2.       SECURITY INTEREST. As security for the Secured Obligations described in
paragraph 3 hereof, the Debtor hereby grants to the Lender a security interest
in and lien on all of the tangible and intangible personal property and fixtures
of the Debtor, including without limitation the property described below,
whether now owned or existing or hereafter acquired or arising, together with
any and all additions thereto and replacements therefor and proceeds and
products thereof (hereinafter referred to collectively as the "Collateral"):

                  (a) all of the Debtor's tangible personal property, including
                  without limitation all present and future goods, inventory
                  (including, without limitation, all printed materials,
                  merchandise, raw materials, work in process, finished goods
                  and supplies), equipment, merchandise, furniture, fixtures,
                  office supplies, motor vehicles, machinery, paper, tools,
                  computers, and associated equipment now owned or hereafter
                  acquired, including, without limitation, the tangible personal
                  property used in the operation of the businesses of the
                  Debtor;

                  (b) to the extent that such rights are assignable as
                  collateral, the Debtor's rights under all present and future
                  authorizations, permits, licenses and franchises issued,
                  granted or licensed to the Debtor for the operation of its
                  business;

                  (c) to the extent that such rights are assignable, all of the
                  Debtor's rights under all present and future vendor or
                  customer contracts and all franchise, distribution,
                  construction, engineering, management, direct marketing and
                  advertising and related agreements; and



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                  (d) all of the Debtor's other personal property, including,
                  without limitation, all present and future accounts, accounts
                  receivable, investment property, rights to proceeds of letters
                  of credit, contract rights, general intangibles (including
                  without limitation, all goodwill, all trademarks, intellectual
                  property, all customer lists, vendor lists, and other printed
                  materials, including all catalogs, indexes, lists, data and
                  other documents and papers relating thereto, blue prints,
                  designs and research and development), any information stored
                  on any medium, including electronic medium, related to any of
                  the personal property of the Debtor, all instruments,
                  documents and chattel paper, and all debts, obligations and
                  liabilities in whatever form owing to the Debtor from any
                  person, firm or corporation or any other legal entity, whether
                  now existing or hereafter arising, now or hereafter received
                  by or belonging or owing to the Debtor, and all guaranties and
                  security therefor.

Any of the foregoing terms which are defined in the Uniform Commercial Code
shall have the meaning provided in the Uniform Commercial Code as supplemented
and expanded by the foregoing.


3.       SECURED OBLIGATIONS. The security interest hereby granted shall secure
the due and punctual payment and performance of the following liabilities and
obligations of the Debtor (herein called the "Secured Obligations"):

                  (a) Principal of and interest on the Loans;

                  (b) Any and all obligations of the Debtor to the Lender under
                  the Notes; and

                  (c) Any and all other obligations of the Debtor to the Lender.


4.       PERFECTION CERTIFICATE. The Debtor has delivered to the Lender a
Perfection Certificate in the form appended hereto as Schedule I. The Debtor
represents to the Lender that the completed Perfection Certificate delivered to
the Lender is true and correct in every respect and the facts contained in such
certificate are accurate. The Debtor shall supplement the Perfection Certificate
promptly after obtaining information which would require a correction or
addition to the Perfection Certificate.

5.       SPECIAL WARRANTIES AND COVENANTS OF THE DEBTOR. The Debtor hereby
warrants and covenants to the Lender that:

                  (a) The address shown at the beginning of this Agreement is
                  the current principal place of business of the Debtor, and all
                  of the Debtor's current additional places of business, if any,
                  and the locations of all of the Collateral currently are
                  listed in the Perfection Certificate delivered pursuant to
                  Section 4 above. The Debtor will not change its principal or
                  any other place of business, or the location of any Collateral
                  from the locations set forth in the Perfection Certificate, or
                  make any change in the Debtor's name or conduct the Debtor's
                  business operations under any fictitious business name or
                  trade name, without, in any such case, at least thirty (30)
                  days' prior written notice to the Lender.

                  (b) Except for the security interest created hereunder and all
                  other security interest granted by the Debtor as of the date
                  hereof, the Debtor is the owner of the Collateral free from
                  any lien, security interest or encumbrance and the Debtor will
                  defend the Collateral against all claims and demands of all
                  persons at any time claiming the same or any interest therein.

                  (c) Except as otherwise consented to in writing by the Lender,
                  the Debtor will not sell or otherwise dispose of any of the
                  Collateral or any interest therein nor will the Debtor create,
                  incur or permit to




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                  exist any mortgage, lien, charge, encumbrance or security
                  interest whatsoever with respect to the Collateral.

                  (d) Except for Collateral that is obsolete or no longer used
                  in the Debtor's business, the Debtor will keep the Collateral
                  in good order and repair (normal wear excepted) and adequately
                  insured at all times. The Debtor will pay promptly when due
                  all taxes and assessments on the Collateral or for its use or
                  operation, except for taxes and assessments contested in good
                  faith and for which adequate reserves are created. The Lender
                  may at its option discharge any taxes, liens, security
                  interests or other encumbrances to which any Collateral is at
                  any time subject, and may, upon the failure of the Debtor to
                  do so in accordance with the terms hereof, purchase insurance
                  on any Collateral and pay for the repair, maintenance or
                  preservation thereof, and the Debtor agrees to reimburse the
                  Lender on demand for any payments or expenses incurred by the
                  Lender pursuant to the foregoing authorization and any
                  unreimbursed amounts shall constitute Secured Obligations for
                  all purposes hereof.

                  (e) The Collateral may be transferred to a third party upon a
                  default without the consent of any other third party.

                  (f) The Debtor will promptly execute and deliver to the Lender
                  such financing statements, certificates and other documents or
                  instruments as may be necessary to enable the Lender to
                  perfect or from time to time renew the security interest
                  granted hereby, including, without limitation, such financing
                  statements, certificates and other documents as may be
                  necessary to perfect a security interest in any additional
                  Collateral hereafter acquired by the Debtor or in any
                  replacements or proceeds thereof. The Debtor authorizes and
                  appoints the Lender, in case of need, to execute such
                  financing statements, certificates and other documents
                  pertaining to the Lender's security interest in the Collateral
                  in its stead, with full power of substitution, as the Debtor's
                  attorney in fact. The Lender may from time to time request and
                  the Debtor shall deliver copies of all customer lists and
                  vendor lists. The Debtor further agrees that a carbon,
                  photographic or other reproduction of a security agreement or
                  financing statement is sufficient as a financing statement
                  under this Agreement.

                  (g) The Debtor will give the Lender notice of each office at
                  which records of the Debtor pertaining to all intangible items
                  of Collateral are kept. Except as may be provided in such
                  notice, the records concerning all intangible Collateral are
                  and will be kept at the address shown at the beginning of this
                  Agreement as the principal place of business of the Debtor.

                  (h) To the extent that the Debtor is a beneficiary under any
                  written Letter of credit now or hereafter issued in favor of
                  the Debtor, the Debtor shall deliver such Letter of credit to
                  the Lender. The Lender shall from time to time, at the request
                  and expense of the Debtor, make such arrangements with the
                  Debtor as are in the Lender's reasonable judgment necessary
                  and appropriate so that the Debtor may make any drawing to
                  which the Debtor is entitled under such Letter of credit,
                  without impairment of the Lender's perfected security interest
                  in the Debtor's rights to the proceeds of such Letter of
                  credit or in the actual proceeds of such drawing. At the
                  Lender's request, the Debtor shall, for any Letter of credit,
                  whether or not written, now or hereinafter issued in favor of
                  the Debtor as beneficiary, execute and deliver to the issuer
                  any confirmer of such Letter of credit an assignment of
                  proceeds form, in favor of the Lender and satisfactory to the
                  Lender and such issuer or (as the case may be) such confirmer,
                  requiring the proceeds of any drawing under such Letter of
                  credit to be paid directly to the Lender for application under
                  the Note.


6.       FIXTURES, ETC. It is the intention of the parties hereto that none of
the Collateral shall become fixtures and the Debtor will take all such
reasonable action or actions as may be necessary to prevent any of the
Collateral



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from becoming fixtures. Without limiting the generality of the foregoing, the
Debtor will, if requested by the Lender, use commercially reasonable efforts to
obtain waivers of lien, in form satisfactory to the Lender, from each lessor of
real property on which any of the Collateral is or is to be located.


7.       EVENTS OF DEFAULT. The Debtor shall be in default under this Agreement
(an "Event of Default") upon the happening of any Event of Default under the
Notes.


8.       RIGHTS AND REMEDIES OF LENDER. Upon the occurrence of any Event of
Default, such default not having previously been waived, remedied or cured, the
Lender shall have the following rights and remedies:

                  (a) All rights and remedies provided by law, including,
                  without limitation, those provided by the Uniform Commercial
                  Code;

                  (b) All rights and remedies provided in this Agreement; and

                  (c) All rights and remedies provided in any other agreement,
                  document or instrument pertaining to the Secured Obligations.


9.       RIGHT OF LENDER TO DISPOSE OF COLLATERAL, ETC. Upon the occurrence of
any Event of Default, such Event of Default not having previously been waived,
remedied or cured, but subject to the provisions of the Uniform Commercial Code
or other applicable law, the Lender shall have the right to take possession of
the Collateral and, in addition thereto, the right to enter upon any premises on
which the Collateral or any part thereof may be situated and remove the same
therefrom. The Lender may require the Debtor to make the Collateral (to the
extent the same is moveable) available to the Lender at a place to be designated
by the Lender which is reasonably convenient to both parties or transfer any
information related to the Collateral to the Lender by electronic medium. Unless
the Collateral is perishable or threatens to decline speedily in value or is of
a type customarily sold on a recognized market, the Lender will give the Debtor
at least ten (10) days' prior written notice in accordance with paragraph 18
hereof of the time and place of any public sale of any of the Collateral or of
the time after which any private sale or any other intended disposition thereof
is to be made. Any such notice shall be deemed to meet any requirement hereunder
or under any applicable law (including the Uniform Commercial Code) that
reasonable notification be given of the time and place of such sale or other
disposition.


10.      NOTE. Notwithstanding any other provision of this Agreement, the rights
of the parties hereunder are subject to the provisions of the Note.


11.      RIGHT OF LENDER TO USE AND OPERATE COLLATERAL, ETC. Upon the occurrence
of any Event of Default, such default not having previously been waived,
remedied or cured, but subject to the provisions of the Uniform Commercial Code
or other applicable law, the Lender shall have the right and power to take
possession of all or any part of the Collateral, and to exclude the Debtor and
all persons claiming under the Debtor wholly or partly therefrom, and thereafter
to hold, store, and/or use, operate, manage and control the same. Upon any such
taking of possession, the Lender may, from time to time, at the expense of the
Debtor, make all such repairs, replacements, alterations, additions and
improvements to and of the Collateral as the Lender may deem proper. In any such
case the Lender shall have the right to manage and control the Collateral and to
carry on the business and to exercise all rights and powers of the Debtor in
respect thereto as the Lender shall deem best, including the right to enter into
any and all such agreements with respect to the operation of the Collateral or




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any part thereof as the Lender may see fit; and the Lender shall be entitled to
collect and receive all rents, issues, profits, fees, revenues and other income
of the same and every part thereof. Such rents, issues, profits, fees, revenues
and other income shall be applied to pay the expenses of holding and operating
the Collateral and of conducting the business thereof, and of all maintenance,
repairs, replacements, alterations, additions and improvements, and to make all
payments which the Lender may be required or may elect to make, if any, for
taxes, assessments, insurance and other charges upon the Collateral or any part
thereof, and all other payments which the Lender may be required or authorized
to make under any provision of this Agreement (including legal costs and
attorneys' fees). The remainder of such rents, issues, profits, fees, revenues
and other income shall be applied as provided in paragraph 13. Without limiting
the generality of the foregoing or limiting in any way the rights of the Lender
under applicable law, at any time after (i) the entire principal balance of any
Loan shall have become due and payable (whether at maturity, by acceleration or
otherwise) and (ii) the Lender shall have provided to the Debtor not less than
ten (10) days prior written notice of its intention to apply for a receiver, the
Lender shall be entitled to apply for and have a receiver appointed under state
or federal law by a court of competent jurisdiction in any action taken by the
Lender to enforce its rights and remedies hereunder in order to manage, protect,
preserve, sell and otherwise dispose of all or any portion of the Collateral and
continue the operation of the business of the Debtor, and to collect all
revenues and profits thereof and apply the same to the payment of all expenses
and other charges of such receivership, including the compensation of the
receiver, and to the payment of the Secured Obligations as aforesaid until a
sale or other disposition of such Collateral shall be finally made and
consummated. THE DEBTOR HEREBY IRREVOCABLY CONSENTS TO AND WAIVES ANY RIGHT TO
OBJECT TO OR OTHERWISE CONTEST THE APPOINTMENT OF RECEIVER AS PROVIDED ABOVE.
THE DEBTOR (I) GRANTS SUCH WAIVER AND CONSENT KNOWINGLY AFTER HAVING DISCUSSED
THE IMPLICATIONS THEREOF WITH COUNSEL, (II) ACKNOWLEDGES THAT (A) THE
UNCONTESTED RIGHT TO HAVE A RECEIVER APPOINTED FOR THE FOREGOING PURPOSES IS
CONSIDERED ESSENTIAL BY THE LENDER IN CONNECTION WITH THE ENFORCEMENT OF IT S
RIGHTS AND REMEDIES HEREUNDER AND UNDER THE NOTE, AND (B) THE AVAILABILITY OF
SUCH APPOINTMENT AS A REMEDY UNDER THE FOREGOING CIRCUMSTANCES WAS A MATERIAL
FACTOR IN INDUCING THE LENDER TO MAKE THE LOANS TO THE DEBTOR, AND (III) AGREES
TO ENTER INTO ANY AND ALL STIPULATIONS IN ANY LEGAL ACTIONS, OR AGREEMENTS OR
OTHER INSTRUMENTS IN CONNECTION WITH THE FOREGOING AND TO COOPERATE FULLY WITH
THE LENDER IN CONNECTION WITH THE ASSUMPTION AND EXERCISE OF CONTROL BY THE
RECEIVER OVER ALL OR ANY PORTION OF THE COLLATERAL. THE LENDER ACKNOWLEDGES AND
AGREES THAT NOTHING IN THIS PARAGRAPH 11 SHALL BE DEEMED TO CONSTITUTE A WAIVER
OF THE DEBTOR'S RIGHT TO FILE FOR PROTECTION UNDER TITLE 11 OF THE UNITED STATES
CODE AT ANY TIME PRIOR TO THE APPOINTMENT OF A RECEIVER.


12.      COLLECTION OF ACCOUNTS RECEIVABLE, ETC. Upon the occurrence of any
Event of Default, such default not having previously been waived, remedied or
cured, the Lender may notify or may require the Debtor to notify account
debtors, including without limitation, customers and vendors, obligated on any
or all of the Debtor's accounts receivable, whether now existing or hereafter
arising, to make payment directly to the Lender, and may take possession of all
proceeds of any accounts in the Debtor's possession, and may take any other
steps which the Lender deems necessary or advisable to collect any or all such
accounts receivable or other Collateral or proceeds thereof.


13.      PROCEEDS OF COLLATERAL. After deducting all costs and expenses of
collection, storage, custody, sale or other disposition and delivery (including
legal costs and attorneys' fees) and all other charges against the Collateral,
the residue of the proceeds of any such sale or disposition shall be applied to
the payment of the Secured Obligations in such order of priority as the Lender
shall determine (consistent with the Credit


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Agreement) and any surplus shall be returned to the Debtor or to any person or
party lawfully entitled thereto (including, if applicable, any subordinated
creditors of the Debtor). By way of enlargement and not by way of limitation of
the rights of the Lender under applicable law or the Note, the Lender shall be
entitled to allocate its application of the Collateral, and the proceeds
thereof, to the Secured Obligations (including without limitation the Loans) in
such proportions and in such order as the Lender, in its sole discretion, shall
decide (consistent with the Note). In the event the proceeds of any sale, lease
or other disposition of the Collateral hereunder are insufficient to pay all of
the Secured Obligations in full, the Debtor will be liable for the deficiency,
together with interest thereon at the maximum rate provided in the Note, and the
cost and expenses of collection of such deficiency, including (to the extent
permitted by law), without limitation, reasonable attorneys' fees, expenses and
disbursements.


14.      WAIVERS, ETC. The Debtor hereby waives presentment, demand, notice,
protest and, except as is otherwise provided herein, all other demands and
notices in connection with this Agreement or the enforcement of the Lender's
rights hereunder or in connection with any Secured Obligations or any
Collateral; consents to and waives notice of the granting of renewals,
extensions of time for payment or other indulgences to the Debtor or to any
account debtor in respect of any account receivable or to any other third party,
or substitution, release or surrender of any Collateral, the addition or release
of persons primarily or secondarily liable on any Secured Obligation or on any
account receivable or other Collateral, the acceptance of partial payments on
any Secured Obligation or on any account receivable or other Collateral and/or
the settlement or compromise thereof. No delay or omission on the part of the
Lender in exercising any right hereunder shall operate as a waiver of such right
or of any other right hereunder. Any waiver of any such right on any one
occasion shall not be construed as a bar to or waiver of any such right on any
future occasion. THE DEBTOR FURTHER WAIVES ANY RIGHT IT MAY HAVE UNDER THE
CONSTITUTION OF THE STATE OF NEW YORK, UNDER THE CONSTITUTION OF ANY STATE IN
WHICH ANY OF THE COLLATERAL MAY BE LOCATED, OR UNDER THE CONSTITUTION OF THE
UNITED STATES OF AMERICA, TO NOTICE (OTHER THAN ANY REQUIREMENT OF NOTICE
PROVIDED HEREIN) OR TO A JUDICIAL HEARING PRIOR TO THE EXERCISE OF ANY RIGHT OR
REMEDY PROVIDED BY THIS AGREEMENT TO THE LENDER AND WAIVES ITS RIGHTS, IF ANY,
TO SET ASIDE OR INVALIDATE ANY SALE DULY CONSUMMATED IN ACCORDANCE WITH THE
FOREGOING PROVISIONS HEREOF ON THE GROUNDS (IF SUCH BE THE CASE) THAT THE SALE
WAS CONSUMMATED WITHOUT A PRIOR JUDICIAL HEARING. The Debtor's waivers under
this section have been made voluntarily, intelligently and knowingly and after
the Debtor has been apprized and counseled by its attorneys as to the nature
thereof and its possible alternative rights.


15.      TERMINATION; ASSIGNMENT, ETC. This Agreement and the security interest
in the Collateral created hereby shall terminate when all of the Secured
Obligations have been paid and finally discharged in full and no Lender is
obligated to make additional Loans under the Credit Agreement. In such event,
the Lender agrees to execute appropriate releases of liens on the Collateral. No
waiver by the Lender or by any other holder of Secured Obligations of any
default shall be effective unless in writing nor operate as a waiver of any
other default or of the same default on a future occasion. In the event of a
sale or assignment of part or all of the Secured Obligations by the Lender, the
Lender may assign or transfer its respective rights and interest under this
Agreement in whole or in part to the purchaser or purchasers of such Secured
Obligations, whereupon such purchaser or purchasers shall become vested with all
of the powers and rights of the Lender hereunder.


16.      REINSTATEMENT. Notwithstanding the provisions of paragraph 15, this
Agreement shall continue to be effective or be reinstated, as the case may be,
if at any time any amount received by the Lender in respect of the Secured
Obligations is rescinded or must otherwise be restored or returned by the Lender
upon the insolvency,


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bankruptcy, dissolution, liquidation or reorganization of the Debtor or any
subsidiary or upon the appointment of any intervener or conservator of, or
trustee or similar official for, the Debtor or any subsidiary or any substantial
part of any of their properties, or otherwise, all as though such payments had
not been made.


17.      GOVERNMENTAL APPROVAL. Prior to or, where permitted, upon the exercise
by the Lender of any power, right, privilege or remedy pursuant to this
Agreement which requires any consent, approval, registration, qualification or
authorization of any governmental authority or instrumentality, the Debtor will
execute and deliver, or will cause the execution and delivery of, all
applications, certificates, instruments and other documents and papers that the
Debtor may be required to obtain for such governmental consent, approval,
registration, qualification or authorization.


18.      NOTICES. All notices, consents, approvals, elections and other
communications hereunder shall be in writing (whether or not the other
provisions of this Agreement expressly so provide) and shall be deemed to have
been duly given if delivered by hand or overnight courier service, mailed by
certified or registered mail or sent by telephonic facsimile (fax), as follows:
(i) if to the Lender, to CMGI, Inc., 100 Brickstone Square, Andover,
Massachusetts, 01810, Attention: Chief Financial Officer, and (ii) if to the
Debtor, to Engage, Inc., 100 Brickstone Square, Andover, Massachusetts 01810,
Attention: Chief Executive Officer.


19.      MISCELLANEOUS. This Agreement shall inure to the benefit of the Lender
and be binding upon the Lender and the Debtor and their respective successors
and assigns. In case any provision in this Agreement shall be invalid, illegal
or unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby. This Agreement
may be executed in any number of counterparts and by the different parties
hereto on separate counterparts, each of which shall be an original, but all of
which together shall constitute one instrument.


20.      GOVERNING LAW; JURISDICTION; WAIVER OF JURY TRIAL. This Agreement,
including the validity hereof and the rights and obligations of the parties
hereunder, shall be construed in accordance with and governed by the laws of the
Commonwealth of Massachusetts. The Debtor, to the extent that it may lawfully do
so, hereby consents to service of process, and to be sued, in the Commonwealth
of Massachusetts and consents to the jurisdiction of the courts of the
Commonwealth of Massachusetts and the United States District Court for the
District of Massachusetts, as well as to the jurisdiction of all courts to which
an appeal may be taken from such courts, for the purpose of any suit, action or
other proceeding arising out of any of the Secured Obligations or with respect
to the transactions contemplated hereby, and expressly waives any and all
objections it may have as to venue in any such courts. The Debtor further agrees
that a summons and complaint commencing an action or proceeding in any of such
courts shall be properly served and shall confer personal jurisdiction if served
personally or by certified mail to it at its address provided in paragraph 18
hereof or as otherwise provided under the laws of the Commonwealth of
Massachusetts.

THE DEBTOR IRREVOCABLY WAIVES ALL RIGHT TO A TRIAL BY JURY IN ANY PROCEEDING
HEREAFTER INSTITUTED BY OR AGAINST THE DEBTOR IN RESPECT OF ITS OBLIGATIONS
HEREUNDER OR THE TRANSACTIONS CONTEMPLATED HEREBY.



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IN WITNESS WHEREOF, the parties have executed this Agreement as a sealed
instrument as of the date first above written.

                                        ENGAGE, INC.


                                        By:  /s/ Christopher Cuddy
                                             ---------------------------------
                                             Name: Christopher Cuddy
                                             Title:  Chief Executive Officer


                                        CMGI, INC.


                                        By:  /s/ David Andonian
                                             ---------------------------------
                                             Name: David Andonian
                                             Title:  Chief Operating Officer