Document:

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                                                                   EXHIBIT 10.10

                                  CMGI, INC.

                    AMENDMENT NO. 3 TO EMPLOYMENT AGREEMENT

                                        August 3, 2001

Mr. David S. Wetherell
CMGI, Inc.
100 Brickstone Square
Andover, MA 01810

Dear Dave:

     This Amendment No. 3 to Employment Agreement amends the Employment
Agreement between you and CMGI, Inc. (the "Company"), dated as of November 9,
1993, as amended (the "Employment Agreement").  In consideration of the premises
herein contained and other good and valuable consideration, you and the Company
agree as follows:

     1.   Amendment of Employment Agreement.  Section 3A of the Employment
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Agreement is hereby deleted in its entirety and replaced with following which is
effective as of August 1, 2001:

     "3A. Base Salary.  As compensation for your services, the Company shall pay
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to you a Base Salary at the annual rate of $1.00 plus such amounts as are
determined by the Board (or the Human Resources and Compensation Committee
thereof) as necessary to cover your Medicare, auto lease, medical, dental,
vision and similar deductions, plus such additional amounts as may be determined
from time to time by the Board (or the Human Resources and Compensation
Committee thereof) in its sole discretion and designated as increases in Base
Salary. Any such increase in Base Salary may not be subsequently reduced or
eliminated without your consent, except as part of a general reduction of
executive salaries."

     2.   Continuing Effect of Employment Agreement.  Except as amended hereby,
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the Employment Agreement shall remain in full force and effect.

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     IN WITNESS WHEREOF, you and the Company have caused this Agreement to be
executed as of the date set forth above.

                                                       CMGI, INC.

                                                       By: /s/ Jeffrey Yanagi
                                                           ------------------
                                                       Name: Jeffrey Yanagi
                                                       Title: EVP HR

                                                       ACCEPTED AND AGREED TO:

                                                       /s/ David S. Wetherell
                                                       ----------------------
                                                       David S. Wetherell<PAGE>

                                                                   EXHIBIT 10.11

                         EXECUTIVE RETENTION AGREEMENT
                         -----------------------------

     THIS EXECUTIVE RETENTION AGREEMENT ("Agreement") by and between CMGI, Inc.,
a Delaware corporation (the "Company") headquartered 100 Brickstone Square,
Andover, Massachusetts and  David Andonian (the "Executive"), is made as of July
9, 2001.

     WHEREAS, the Board of Directors of the Company (the "Board") has determined
that Executive plays 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
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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.
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(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). Additionally, on the Executive's
last day of employment, the vesting of each of the stock options to purchase
shares of common stock of the Company set forth on Exhibit A hereto shall be
                                                   ---------
accelerated in full, such that the Executive shall be entitled to exercise such
stock options (in accordance with the exercise terms and conditions set forth in
the option agreement and/or plan pursuant to which such stock options were
granted) to the same extent as he would have been entitled had he been
continuously employed by the Company until the end of the vesting period related
to each such stock option. The Executive agrees that after the Termination Date,
but prior to payment of the severance pay, bonus and acceleration of stock
options 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, bonus and the acceleration of options called for by this paragraph are
contingent on his execution of the previously described release of claims.
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(b)  Severance Pay Absent a Change in Control.  In the event the employment of
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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 semi-monthly 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 (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
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this Section 2 (and applicable acceleration of options) 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
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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 for his personal use 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 during the Employment Period: (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

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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.

4.    Miscellaneous.
      -------------

(a)   Notices.  Any notices delivered under this Agreement shall be deemed duly
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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, or if the Executive holds the position of General Counsel as of the
Termination Date, the Company's Chief Financial Officer.

(b)   Pronouns.  Whenever the context may require, any pronouns used in this
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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
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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
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instrument executed by both the Company and the Executive.

(e)   Governing Law.  This Agreement shall be governed by and construed in
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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 or
her.

(g)   Waivers.  No delay or omission by the Company in exercising any right
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under this Agreement shall operate as a waiver of that or any other right. A
waiver or consent given by the

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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
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convenience of reference only and in no way define, limit or affect the scope or
substance of any section of this Agreement.

(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 HR

                              /s/ David Andonian
                              -------------------
                              David Andonian

                                      -4-
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                                   EXHIBIT A

Options to purchase CMGI Common Stock granted on:

September 15, 1999

July 25, 2000

July 9, 2001

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