Exhibit 10.1

AMENDMENT OF EXECUTIVE SEVERANCE AGREEMENT

This Amendment of Executive Severance Agreement is entered into this 4th day of
January, 2008, by and between CMGI, Inc, a Delaware corporation (the “Company”)
and Joseph C. Lawler (the “Executive”).

WHEREAS, the parties entered into that certain Executive Severance Agreement
dated as of August 23, 2004 (“Agreement”); and

WHEREAS, the parties desire to amend the Agreement in accordance with the
provisions of Section 409A of the Internal Revenue Code of 1986, as amended
(“Code”).

NOW THEREFORE, the parties hereto agree as follows:

Unless the context indicates otherwise, capitalized terms used and not defined
in this Amendment shall have the respective meanings assigned thereto by the
Agreement.

Section 3 is amended by adding new Section 3(e) at the end thereof, as follows:

“(e) Anything herein to the contrary notwithstanding, if on the Executive’s last
day of employment the Executive is a “specified employee” of the Company (as
defined in Treasury Regulation Section 1.409A-1(i)) and if the severance
payments due to the Executive under Section 3(a) or Section 3(b) hereof, as the
case may be, do not constitute a “short-term deferral of compensation” under
Treasury Regulation Section 1.409A-1(b)(4), the following provisions shall
apply:

(i) If such severance payments are payable on account of the Executive’s
“involuntary separation from service” (as defined in Treasury Regulation
Section 1.409A-1(n)), the Executive shall receive such amount of his severance
payments during the six (6)-month period immediately following the last day of
the Executive’s employment as equals the lesser of (“Limitation Amount”):
(x) such severance payment amount payable to him under Section 3(a) or
Section 3(b) during such six (6)-month period or (y) two (2) multiplied by the
compensation limit in effect under Section 401(a)(17) of the Code of 1986, as
amended (“Code”), for the calendar year in which the last day of the Executive’s
employment occurs.

(ii) To the extent that, upon such “involuntary separation from service,” the
amount of severance payments that would have been payable to the Executive under
Section 3(a) or Section 3(b) during the six (6)-month period following the last
day of his employment exceeds the Limitation Amount, such excess shall be paid
on the first regular payroll date following the expiration of such six (6)-month
period.

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(iii) If the Company reasonably determines that such employment termination is
not such an “involuntary separation from service,” all severance payments that
would have been payable to the Executive under Section 3(a) or Section 3(b)
during the six (6)-month period immediately following the last day of the
Executive’s employment, but for such determination, shall be paid on the first
regular payroll date immediately following the expiration of such six (6)-month
period following the last day of the Executive’s employment.”

The definition of “Good Reason” under Section 4(b) is deleted in its entirety
and replaced as follows:

“ “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 Waltham, Massachusetts, (ii) a reduction in the Executive’s
(A) then-current base salary without the Executive’s consent, or (B) target
bonus or a material reduction in benefits without the Executive’s consent, or
unless other executive officers are similarly treated, (iii) material diminution
of Executive’s duties, authority or position as Chief Executive Officer of the
Company, without the Executive’s consent, (iv) any amendment following the date
hereof to the officer indemnification provisions contained in Article Ninth of
the Company’s certificate of incorporation that materially reduces the
indemnification benefits to the Executive, (v) the failure of the Company to
assign and of any successor to assume the obligations of the Company under this
Agreement and the Letter Agreement, (vi) the inability of the Company to
otherwise grant such any portion Special Awards when due, or (vi) the death or
permanent and total disability (as defined in Section 22(e)(3) of the Code) of
the Executive. Notwithstanding, the Executive shall not have “Good Reason” to
voluntarily terminate his employment unless and until: (x) he provides notice to
the Company of the event or condition constituting Good Reason not later than
ninety (90) days after the occurrence thereof and (y) thirty (30) days shall
have elapsed following such notice during which the Company has not remedied
such event or condition.”

Section 7 is amended to add new Section 7(j) at the end thereof , as follows:

(j) This Agreement is intended to comply with the provisions of Section 409A and
the Agreement shall, to the extent practicable, be construed in accordance
therewith. No payments to be made under this Agreement may be accelerated or
deferred except as specifically permitted under Section 409A. In the event that
any payment or benefit under this Agreement is determined by the Company to be
in the nature of deferred compensation, the Company and the Executive hereby
agree to take such actions, not otherwise provided herein, as may be mutually
agreed between the parties to ensure that such payments comply with the
applicable provisions of Section 409A of the Code and the Treasury regulations
thereunder.

 

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The Agreement is affirmed, ratified and continued, as amended hereby.

IN WITNESS WHEREOF, the parties hereto have signed their names as of the day and
year first written above.

 

CMGI, Inc. By:   /s/ Peter L. Gray   Its:   Executive Vice President and General
Counsel /s/ Joseph C. Lawler Joseph C. Lawler

 

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