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                                                                EXHIBIT 10.2.4.3

                                    ADDENDUM
                                       TO
                             STOCK OPTION AGREEMENT


      The following provisions are hereby incorporated into, and are hereby made
a part of, that certain Stock Option Agreement (the "Option Agreement") by and
between Ask Jeeves, Inc. (the "Corporation") and Steve Sordello ("Optionee")
evidencing the stock option to purchase 30,000 shares of the Corporation's
Common Stock (the "Option") granted this day to Optionee under the terms of the
Corporation's 1999 Equity Incentive Plan, and such provisions are effective
immediately.

      All capitalized terms in this Addendum, to the extent not otherwise
defined herein, shall have the meanings assigned to them in the Option
Agreement.

            INVOLUNTARY TERMINATION/AUTHORIZED RESIGNATION FOLLOWING
                     CHANGE IN CONTROL/BUSINESS SEGMENT SALE

      1. To the extent the Option is to be assumed or otherwise continued in
effect in connection with a Change in Control or Business Segment Sale, the
Option shall not, upon the occurrence of that Change in Control or Business
Segment Sale, accelerate as to any of the shares at the time subject to the
Option (the "Option Shares"), and the Option shall accordingly continue, over
Optionee's period of Continuous Service following such Change in Control or
Business Segment Sale, to vest and become exercisable for those Option Shares in
one or more installments in accordance with the normal vesting schedule for the
Option set forth in the Option Agreement. However, immediately upon an
Involuntary Termination of Optionee's Continuous Service within twelve (12)
months following such Change in Control or Business Segment Sale or an
Authorized Resignation in connection with such Change in Control or Business
Segment Sale, the Option, to the extent outstanding at that time but not
otherwise fully vested and exercisable, shall vest in full and become
immediately exercisable for all of the Option Shares at the time subject to the
Option and may be exercised for any or all of those Option Shares as fully
vested shares.

      2. The Option as so accelerated shall remain exercisable for any or all of
the Option Shares until the earlier of (i) the expiration date of the Option set
forth in the Option Agreement or (ii) the sooner termination of the Option in
accordance with the applicable provisions of the Option Agreement or Section 11
of the Plan.

      3. For purposes of this Addendum the following definitions shall be in
effect:

      AUTHORIZED RESIGNATION shall mean the Optionee's resignation from
employment with the Corporation (or any successor entity) for any reason within
the ninety (90)-day period beginning six (6) months after the effective date of
a Change in Control or Business Segment Sale.


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      BUSINESS SEGMENT SALE shall mean the sale or other spinoff of all or
substantially all of the assets primarily attributable to the Corporation's
operation of the Web Properties line of business.

      CHANGE IN CONTROL shall mean a change in the ownership or control of the
Corporation effected through any of the following transactions:

            (A) a merger, consolidation or reorganization approved by the
      Corporation's stockholders, unless securities representing more than fifty
      percent (50%) of the total combined voting power of the outstanding voting
      securities of the successor corporation are immediately thereafter
      beneficially owned, directly or indirectly and in substantially the same
      proportion, by the persons who beneficially owned the Corporation's
      outstanding voting securities immediately prior to such transaction;

            (B) any stockholder-approved sale, transfer or other disposition of
      all or substantially all of the Corporation's assets in complete
      liquidation or dissolution of the Corporation;

            (C) any transaction or series of related transactions pursuant to
      which any person or any group of persons comprising a "group" within the
      meaning of Rule 13d-5(b)(1) under the Securities Exchange Act of 1934, as
      amended (other than the Corporation or a person that, prior to such
      transaction or series of related transactions, directly or indirectly
      controls, is controlled by or is under common control with, the
      Corporation) becomes directly or indirectly the beneficial owner (within
      the meaning of Rule 13d-3 of the Securities Exchange Act of 1934, as
      amended) of securities possessing (or convertible into or exercisable for
      securities possessing) thirty-five percent (35%) or more of the total
      combined voting power of the Corporation's securities (determined by the
      power to vote with respect to the elections of Board members) outstanding
      immediately after the consummation of such transaction or series of
      related transactions, whether such transaction involves a direct issuance
      from the Corporation or the acquisition of outstanding securities held by
      one or more of the Corporation's stockholders; or

            (D) a change in the composition of the Board over a period of
      thirty-six (36) consecutive months or less such that a majority of the
      Board members ceases, by reason of one or more contested elections for
      Board membership, to be comprised of individuals who either (A) have been
      Board members continuously since the beginning of such period or (B) have
      been elected or nominated for election as Board members during such period
      by at least a majority of the Board members described in clause (A) who
      were still in office at the time the Board approved such election or
      nomination.

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      An INVOLUNTARY TERMINATION shall mean the termination of Optionee's
Continuous Service by reason of:

            (A) Optionee's involuntary dismissal or discharge by the Corporation
      (or any successor entity) for reasons other than Misconduct, or

            (B) Optionee's voluntary resignation following (i) a reduction in
      Optionee's level of compensation (including base salary, fringe benefits
      and target bonus under any corporate performance based bonus or incentive
      programs) by more than fifteen percent (15%) or (ii) a relocation of
      Optionee's place of employment by more than fifty (50) miles, provided and
      only if such reduction or relocation is effected by the Corporation
      without Optionee's consent.

      MISCONDUCT shall mean the commission of any act of fraud, embezzlement or
dishonesty by Optionee, any unauthorized use or disclosure by Optionee of
confidential information or trade secrets of the Corporation (or any Affiliate),
or any other intentional misconduct by Optionee adversely affecting the business
or affairs of the Corporation (or any Affiliate) in a material manner. The
foregoing definition shall not in any way preclude or restrict the right of the
Corporation (or any Affiliate) to discharge or dismiss Optionee or any other
person in the service of the Corporation (or any Affiliate) for any other acts
or omissions, but such other acts or omissions shall not be deemed, for purposes
of this Agreement, to constitute grounds for termination for Misconduct.

      IN WITNESS WHEREOF, Ask Jeeves, Inc. has caused this Addendum to be
executed by its duly authorized officer as of the Effective Date specified
below.

                                    ASK JEEVES, INC.


                                    By:   /s/ A. George (Skip) Battle
                                          ---------------------------------
                                    Title: Chief Executive Officer
                                          ---------------------------------







EFFECTIVE DATE:           April 1  , 2003
               --------------------



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