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                                                                   EXHIBIT 10.43

                            INCENTIVE BONUS AGREEMENT

         This Incentive Bonus Agreement (the "Agreement"), effective as of
October 23, 2003 ("Effective Date"), is by and between Bernard Harguindeguy
("Harguindeguy") and Critical Path, Inc. ("CP") (each a "Party"; together the
"Parties").

         A.       CP is currently pursuing options relating to a possible sale
(the "Sale") to a third party (the "Buyer") of a portion of its products and
related assets and business constituting its Identity Management business (the
"Business").

         B.       Harguindeguy is willing to assist CP in consummating a Sale as
requested by CP.

         NOW, THEREFORE, in consideration of the foregoing premises and the
covenants, representations, conditions and agreements contained herein, the
Parties hereby agree as follows:

         1.       Mr. Harguindeguy will fully cooperate with any potential Buyer
in regards to due diligence efforts, and the identification of employees who may
transition out of CP to the Buyer's employ.

         2.       Subject to the conditions specified herein, within 30 days
after the close of a Sale in which Harguindeguy has fully cooperated, made
material contributions and played an active and positive role in closing,
Harguindeguy will be paid a bonus based on the net proceeds received by the CP
for the Sale in accordance with the schedule attached hereto as Exhibit A.

         3.       At the request of CP or a Buyer, Harguindeguy agrees to remain
employed by the Buyer for a period of 6 months after the close of the Sale to
assist in the transition of the Business to the Buyer, provided he is reasonably
compensated for such services in an amount no less than an annual base salary of
$200,000, paid in a manner to be determined by the Buyer.

         4.       The Parties acknowledge and agree that this Agreement is not
an employment contract and that Harguindeguy has the right to resign and the CP
has the right to terminate his employment at any time, for any reason, with or
without cause. Harguindeguy acknowledges and agrees that this Agreement does not
purport to set forth or modify any of the terms and conditions of his
employment, and that as an employee of CP he has obligations to CP which are not
set forth in this Agreement.

         5.       The terms and conditions contained herein constitute the
entire agreement between the Parties and supersede all other previous and
contemporaneous agreements and understandings, whether oral or written, between
the Parties hereto with respect to the subject matter hereof. This Agreement,
and all disputes arising out of or related thereto, shall be governed by and
construed under the laws of the State of California without reference to
conflict of laws principles. No amendment or modification of this Agreement, nor
waiver of any rights under this Agreement, shall be valid unless in writing
signed by each Party. The waiver of a breach of any term hereof shall in no way
be construed as a waiver of any term or other breach hereof. If any provision of
this Agreement is held by a court of competent jurisdiction to be contrary to
law the remaining provisions of this Agreement shall remain in full force and
effect.

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         IN WITNESS WHEREOF, the Parties have executed this Agreement effective
as of the date first written above.

Bernard Harguindeguy                       CRITICAL PATH, INC.

By: /s/ Bernard Harguindeguy               By: /s/ Michael J. Zukerman
   -----------------------------                ------------------------------

Name: Bernard Harguindeguy                 Name:  Michael J. Zukerman

                                           Title: SVP and General Counsel

Date: October 23, 1999                     Date:  October 23, 1999

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