Document:

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                                                                 EXHIBIT 10.42.4

                                    AMENDMENT
                            Dated as of March 1, 2002

WHEREAS, ACTV, INC., a Delaware corporation having an office at 233 Park Avenue
South, New York, New York 10003 (hereinafter referred to as "Employer"), and
BRUCE J. CROWLEY, an individual residing at 257 West 17th Street, New York, New
York 10011, are parties to that certain Employment Agreement dated as of August
1, 1995 (as heretofore amended by that certain Salary Amendment dated as of
September 1, 2001, the "Agreement"); and

WHEREAS, the parties desire to amend the Agreement, effective the date hereof,
to restate the option exercise provisions set forth in Section 4.g thereof as
hereinbelow set forth;

NOW, THEREFORE, the parties hereby agree as follows:

1. Amendment. Section 4.g of the Agreement is hereby deleted therefrom in its
entirety, and a new Section 4.g is hereby inserted in place thereof, such new
Section 4.g to be and read as follows:

                  "g. Unless a pre-existing plan of Employer expressly forbids
it, Employee may pay the exercise price (the "Exercise Price") of any and all
Rights that are or become exercisable at any time during the term hereof (the
respective Employer securities underlying any such Rights being herein referred
to as the "Underlying Securities"), by any, or any combination, of the following
means:

                  "(i) by Employee's execution and delivery of a full recourse
promissory note drawn payable to Employer in a principal amount equal to the
Exercise Price, which note shall bear interest at a market rate to be
established at the date of the respective exercise, shall (without limiting the
full recourse nature thereof) be secured by such of the respective Underlying
Securities as Employee shall thereby be exercising upon, shall become due and
payable on not later than the due date specified therein, the expiration date of
this Agreement or, on a pro rata basis, the disposition of any or all of the
Underlying Securities constituting security therefor, and shall provide that the
principal amount thereof (together with all interest accrued thereon) may be
prepaid in its entirety at any time without penalty, and shall be paid in its
entirety when the same shall become due and payable, either in cash or pursuant
to subsection (ii) hereof, or by any combination thereof, as Employee may elect
with respect to any such payment;

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                  "(ii) by Employee's transfer to Employer of such number of
shares of ACTV common stock as Employee shall have owned for at least six months
and shall, at the date of Employee's delivery and transfer thereof to ACTV, have
a fair market value equal to the Exercise Price (or such portion of the Exercise
Price as Employee shall then be paying thereby); or

                  "(iii) by a cash amount equal to all or such portion of the
Exercise Price as Employee may elect to pay in cash."

2. Agreement. The Agreement, as amended hereby, is hereby ratified and confirmed
in its entirety and shall continue in full force and effect in accordance with
its terms.

IN WITNESS WHEREOF, the parties have executed this instrument effective as of
the date first set forth above.

                                    ACTV, INC.

                                    By: /s/ David Reese
                                        --------------------------
                                         David Reese,
                                         Chief Executive Officer

                                    /s/ Bruce Crowley
                                    ---------------------------------
                                          BRUCE CROWLEY

..<PAGE>

                                                               EXHIBIT 10.42.5

                                SALARY AMENDMENT
                          Dated as of September 1, 2001
                                       To
                              EMPLOYMENT AGREEMENT

WHEREAS, ACTV, INC. ("ACTV") and BRUCE CROWLEY ("Employee") are parties to an
employment agreement (as the same may have been amended prior to the date
here-of, the "Employment Agreement") pursuant to which ACTV or an affiliate of
ACTV currently employs Employee; and

WHEREAS, in a joint effort to address ACTV's current financial needs, ACTV
desires, and Employee has agreed, to amend the Employment Agreement, effective
as of September 1, 2001, to effect a reduction in the annual salary currently
being paid to Employee thereunder;

NOW, THEREFORE, in consideration of the premises, the parties hereby agree as
follows:

1. Salary Reduction. During the period commencing on the date hereof to and
including the earlier of (i) such date (if any) as the Chief Executive Officer
of ACTV may, in his sole discretion, hereafter rescind this instrument for and
on behalf of ACTV by written notice to Employee or (ii) the date (if any) of any
final disposition of all or substantially all of ACTV's stock, businesses and/or
assets (the date of any such rescission or dispo-sition being a "Rescission
Date"), Employee shall accept a $1,579.00 reduction in his current annual
salary, with the result that from and after September 1, 2001 to and inclu-ding
the Rescission Date, Employee's annual salary under his Employment Agreement
(exclusive of any bonus or other compensation payable thereunder) shall,
notwithstand-ing any provision of Employee's Employment Agreement to the
contrary, be Two Hundred Seventy Five Thousand dollars ($275,000.00), less
applicable withholding taxes and other payroll deductions required by law,
payable in accordance with ACTV's customary payroll practices. Nothing herein
shall be deemed to obligate ACTV (or any ACTV affiliate) to pay to Employee,
prior to, upon or after the Rescission Date (if any), any sum that Employee
shall have foregone prior thereto as a consequence of this instrument, except as
herein otherwise expressly provided in Section 2 below.

2. Severance Adjustment. Any severance that shall become payable to Employee
under his Employment Agreement during or after the term of this instrument shall
be calculated without reference to either this instrument or the salary
reduction effected hereby.

3. Waiver. By his acceptance and execution of this instrument, Employee
acknowledges and confirms his consent hereto and waives any claim that the
herein-specified reduction of his annual salary from the date hereof to and
including the Rescission Date constitutes a breach of, or otherwise provides him
with any right to terminate his employment under, his Employment Agreement.

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4. Ratification. As hereinabove amended, Employee's Employment Agreement is
hereby ratified and confirmed to be in full force and effect.

5. Governing Law. This instrument shall be governed by the laws of the State of
New York, without reference to such State's laws governing conflicts of laws.

IN WITNESS WHEREOF, ACTV and the undersigned Employee have executed this
instrument as of the date first set forth above.

                                     ACTV, INC.

                                     By: ___________________________________
                                         Title:

                                     ---------------------------------------
                                                BRUCE CROWLEY
                                                ("Employee")<PAGE>

                                                                 EXHIBIT 10.42.6

                                                           As of August 28, 2002

ACTV, Inc.
Attn:  Day L. Patterson, Esq.
          General Counsel
233 Park Avenue South, 10th Floor
New York, New York  10003-1606

Re:  Limited Waiver of Certain Employment Agreement Provisions
     ---------------------------------------------------------

Gentlemen,

Reference is made to that certain Employment Agreement dated as of August 1,
1995 (as modified effective January 18, 2001, as set forth in Section 15
thereof, and as otherwise heretofore amended) (the "Agreement") between ACTV,
Inc. ("ACTV") and the under-signed, and specifically to Section 4(b)(ii)
thereof.

For adequate consideration, the receipt and sufficiency of which are hereby
acknow-ledged and confirmed by the undersigned, this letter shall serve as my
irrevocable and unconditional agreement with ACTV that upon the date of any
merger of ACTV with or into Liberty Media Corporation ("LMC") or any LMC
subsidiary or affiliate, I do hereby waive (and, upon the date of any such
merger, I shall thereupon be deemed to have waived, without any further action
by me or any notice to or from me) the special compensation payment provided for
in Section 4(b)(ii) of the Agreement insofar and only insofar as such special
compensation payment would otherwise be payable to me with respect to the
exercise of any stock option(s) theretofore issued to me having an exercise
price of $2.50 or more. Accordingly, from and after the date of any such merger,
ACTV shall not have any obligation under Section 4(b)(ii) of the Agreement to
make any special compensation payment to me for, or otherwise to fund, the
exercise of any stock option(s) theretofore issued to me having an exercise
price of $2.50 or more.

In the event that no merger of ACTV with or into Liberty Media Corporation
("LMC") or any LMC subsidiary or affiliate shall occur prior to December 31,
2003, then this instru-ment shall expire and cease to be of any further force or
effect from and after January 1, 2004.

This agreement and waiver shall be deemed governed by the laws of the State of
New York, without reference to such State's laws governing conflicts of laws.

Sincerely yours,

/s/ Bruce J. Crowley

   Bruce J. Crowley,
Executive Vice President<PAGE>

                                                                EXHIBIT 10.57.1

                                SALARY AMENDMENT
                         Dated as of September 1, 2001
                                       To
                              EMPLOYMENT AGREEMENT

WHEREAS, ACTV, INC. ("ACTV") and KEVIN M. LIGA ("Employee") are parties to an
employment agreement (as the same may have been amended prior to the date
hereof, the "Employment Agreement") pursuant to which ACTV or an affiliate of
ACTV currently employs Employee; and

WHEREAS, in a joint effort to address ACTV's current financial needs, ACTV
desires, and Employee has agreed, to amend the Employment Agreement, effective
as of September 1, 2001, to effect a reduction in the annual salary currently
being paid to Employee thereunder;

NOW, THEREFORE, in consideration of the premises, the parties hereby agree as
follows:

1. Salary Reduction. During the period commencing on the date hereof to and
including the earlier of (i) such date (if any) as the Chief Executive Officer
of ACTV may, in his sole discretion, hereafter rescind this instrument for and
on behalf of ACTV by written notice to Employee or (ii) the date (if any) of any
final disposition of all or substantially all of ACTV's stock, businesses and/or
assets (the date of any such rescission or dispo-sition being a "Rescission
Date"), Employee shall accept a $30,000.00 reduction in his current annual
salary, with the result that from and after September 1, 2001 to and inclu-ding
the Rescission Date, Employee's annual salary under his Employment Agreement
(exclusive of any bonus or other compensation payable thereunder) shall,
notwithstand-ing any provision of Employee's Employment Agreement to the
contrary, be Two Hundred Twenty Thousand dollars ($220,000.00), less applicable
withholding taxes and other payroll deductions required by law, payable in
accordance with ACTV's customary payroll practices. Nothing herein shall be
deemed to obligate ACTV (or any ACTV affiliate) to pay to Employee, prior to,
upon or after the Rescission Date (if any), any sum that Employee shall have
foregone prior thereto as a consequence of this instrument, except as herein
otherwise expressly provided in Section 2 below.

2. Severance Adjustment. Any severance that shall become payable to Employee
under his Employment Agreement during or after the term of this instrument shall
be calculated without reference to either this instrument or the salary
reduction effected hereby.

3. Waiver. By his acceptance and execution of this instrument, Employee
acknowledges and confirms his consent hereto and waives any claim that the
herein-specified reduction of his annual salary from the date hereof to and
including the Rescission Date constitutes a breach of, or otherwise provides him
with any right to terminate his employment under, his Employment Agreement.

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4. Ratification. As hereinabove amended, Employee's Employment Agreement is
hereby ratified and confirmed to be in full force and effect.

5. Governing Law. This instrument shall be governed by the laws of the State of
New York, without reference to such State's laws governing conflicts of laws.

IN WITNESS WHEREOF, ACTV and Employee have executed this instrument as of the
date first set forth above.

                                      ACTV, INC.

                                      By: /s/ David Reese
                                          ---------------------------
                                          Title:

                                      /s/ Kevin M. Liga
                                      -------------------------------
                                          KEVIN M. LIGA
                                               ("Employee")

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