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                                                                    EXHIBIT 10.5

                          EXECUTIVE SEVERANCE AGREEMENT

         THIS EXECUTIVE SEVERANCE AGREEMENT ("Agreement") by and between CMGI,
Inc., a Delaware corporation (the "Company") headquartered at 100 Brickstone
Square, Andover, Massachusetts and Thomas Oberdorf (the "Executive"), is made as
of March 4, 2002.

         WHEREAS, the Board of Directors of the Company (the "Board") has
determined that Executive will play a critical role in the operations of the
Company; and

         WHEREAS, the Board has determined that appropriate steps should be
taken to reinforce and encourage the continued employment and dedication of the
Executive.

         NOW, THEREFORE, as an inducement for and in consideration of the
Executive remaining in its employ, the Company agrees that the Executive shall
receive the severance benefits set forth in this Agreement in the event the
Executive's employment with the Company is terminated under the circumstances
described below.

1.       Not an Employment Contract. The Executive acknowledges that this
Agreement does not constitute a contract of employment or impose on the Company
any obligation to retain the Executive as an employee and that this Agreement
does not prevent the Executive from terminating his employment. Executive
understands and acknowledges that he is an employee at will and that either he
or the Company may terminate the employment relationship between them at any
time and for any reason.

2.       Severance Pay.

(a)      Severance Pay Following a Change in Control. In the event a Change in
Control (as defined below) occurs and, within one (1) year thereafter, the
employment of the Executive is terminated by the Company for a reason other than
for Cause (as defined below) or by the Executive for Good Reason (as defined
below), then the Company shall pay to the Executive (as severance pay) a lump
sum payment equal to (i) his then current base salary multiplied by two (2),
plus (ii) his then current target bonus multiplied by two (2), within 30 days
after the Termination Date (as defined below). The Executive agrees that after
the Termination Date, but prior to payment of the severance pay and bonus called
for by this paragraph, he shall execute a release, based on the Company's
standard form severance agreement, of any and all claims he may have against the
Company and its officers, employees, directors, parents and affiliates.
Executive understands and agrees that the payment of the severance pay and bonus
called for by this paragraph are contingent on his execution of the previously
described release of claims.

(b)      Severance Pay Absent a Change in Control. In the event the employment
of the Executive is terminated by the Company for a reason other than for Cause
(as defined below), then the Company shall continue to pay to the Executive (as
severance pay), (i) his regular base salary as in effect on the Executive's last
day of employment (exclusive of bonus or any other compensation), for one (1)
year following the Termination Date (as defined below), plus (ii) at the end of
such year, the amount of Executive's target bonus as in effect on the
Executive's last day of employment. Unless the parties agree otherwise, the
severance pay provided for in clause

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(i) above shall be paid in installments, in accordance with the Company's
regular payroll practices, and the severance pay set forth in (ii) above shall
be paid within 30 days of the end of the fiscal year to which such amount
relates. The Executive agrees that after the Termination Date, but prior to
payment of the severance pay and bonus called for by this paragraph, he shall
execute a release, based on the Company's standard form severance agreement, of
any and all claims he may have against the Company and its officers, employees,
directors, parents and affiliates. Executive understands and agrees that the
payment of the severance pay and bonus called for by this paragraph are
contingent on his execution of the previously described release of claims.

(c)      Sole Remedy. The payment to the Executive of the amounts payable under
this Section 2 shall constitute the sole remedy of the Executive in the event of
a termination of the Executive's employment by the Company or a resignation by
the Executive that results in payment of benefits under this Section 2.

3.       Definitions. For purposes of this Agreement, the following terms shall
have the following meanings:

(a)      "Cause" shall mean a good faith finding by the Company of: (i) gross
negligence or willful misconduct by Executive in connection with his employment
duties, (ii) failure by Executive to perform his duties or responsibilities
required pursuant to his employment, after written notice and an opportunity to
cure, (iii) mis-appropriation by Executive of the assets or business
opportunities of the Company, or its affiliates, (iv) embezzlement or other
financial fraud committed by Executive, (v) the Executive knowingly allowing any
third party to commit any of the acts described in any of the preceding clauses
(iii) or (iv), or (vi) the Executive's indictment for, conviction of, or entry
of a plea of no contest with respect to, any felony.

(b)      "Good Reason" shall mean: (i) the unilateral relocation by the Company
of the Executive's principal work place for the Company to a site more than 60
miles from Andover, Massachusetts; (ii) a reduction in the Executive's then
current base salary, without the Executive's consent; or (iii) the Executive's
assignment to a position where the duties of the position are outside his area
of professional competence.

(c)      "Change in Control" shall mean the consummation of any of the following
events: (i) a sale, lease or disposition of all or substantially all of the
assets of the Company, or (ii) a sale, merger, consolidation, reorganization,
recapitalization, sale of assets, stock purchase, contribution or other similar
transaction (in a single transaction or a series of related transactions) of the
Company with or into any other corporation or corporations or other entity, or
any other corporate reorganization, where the stockholders of the Company
immediately prior to such event do not retain (in substantially the same
percentages) beneficial ownership, directly or indirectly, of more than fifty
percent (50%) of the voting power of and interest in the successor entity or the
entity that controls the successor entity, provided, however, that no Change in
Control shall be deemed to have occurred due to the conversion or payment of any
equity or debt instrument of the Company which is outstanding on the date
hereof.

(d)      "Termination Date" shall mean the Executive's last day on the payroll
of the Company.

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4.       Miscellaneous.

(a)      Notices. Any notices delivered under this Agreement shall be deemed
duly delivered four business days after it is sent by registered or certified
mail, return receipt requested, postage prepaid, or one business day after it is
sent for next-business day delivery via a reputable nationwide overnight courier
service, in each case to the address of the recipient set forth in the
introductory paragraph hereto. Either party may change the address to which
notices are to be delivered by giving notice of such change to the other party.
All notices to the Company shall also be addressed to the Company's General
Counsel.

(b)      Pronouns. Whenever the context may require, any pronouns used in this
Agreement shall include the corresponding masculine, feminine or neuter forms,
and the singular forms of nouns and pronouns shall include the plural, and vice
versa.

(c)      Entire Agreement.  This Agreement constitutes the entire agreement
between the parties and supersedes all prior agreements and understandings,
whether written or oral, relating to the subject matter of this Agreement.

(d)      Amendment.  This Agreement may be amended or modified only by a written
instrument executed by both the Company and the Executive.

(e)      Governing Law.  This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Massachusetts. Any action, suit
or other legal arising under or relating to any provision of this Agreement
shall be commenced only in a court of the Commonwealth of Massachusetts (or, if
appropriate, a federal court located within Massachusetts), and the Company and
the Executive each consents to the jurisdiction of such a court. The Company and
the Executive each hereby irrevocably waive any right to a trial by jury in any
action, suit or other legal proceeding arising under or relating to any
provision of this Agreement.

(f)      Successors and Assigns. This Agreement shall be binding upon and inure
to the benefit of both parties and their respective successors and assigns,
including any corporation with which or into which the Company may be merged or
which may succeed to its assets or business, provided, however, that the
obligations of the Executive are personal and shall not be assigned by him.

(g)      Waivers. No delay or omission by the Company in exercising any right
under this Agreement shall operate as a waiver of that or any other right. A
waiver or consent given by the Company on any one occasion shall be effective
only in that instance and shall not be construed as a bar or waiver of any right
on any other occasion.

(h)      Captions. The captions of the sections of this Agreement are for
convenience of reference only and in no way define, limit or affect the scope or
substance of any section of this Agreement.

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(i)     Severability. In case any provision of this Agreement shall be invalid,
illegal or otherwise unenforceable, the validity, legality and enforceability of
the remaining provisions shall in no way be affected or impaired thereby.

        THE EXECUTIVE ACKNOWLEDGES THAT HE HAS CAREFULLY READ THIS AGREEMENT AND
UNDERSTANDS AND AGREES TO ALL OF THE PROVISIONS IN THIS AGREEMENT.

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

                                                      CMGI, Inc.


                                                      By: /s/ Jeffrey Yanagi
                                                          -------------------
                                                      Title: EVP Human Resources


                                                      /s/ Thomas Oberdorf
                                                      -------------------
                                                      Thomas Oberdorf

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