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                                                                   EXHIBIT 10.16

                              CRITICAL PATH, INC.

                       1999 NONSTATUTORY STOCK OPTION PLAN

                       NONSTATUTORY STOCK OPTION AGREEMENT

Critical Path, Inc., a California corporation (the "Company"), granted an Option
on October 8, 2001 to purchase shares of its common stock (the "Shares") to the
Optionee named below. The terms and conditions of that Option grant, as amended
and restated, are set forth in this cover sheet, the attachment, the Company's
1999 Nonstatutory Stock Option Plan (the "Plan") and in the Optionee's
employment agreement with the Company dated October 8, 2001.

Date of Option Grant: October 8, 2001
                      ---------------

Name of Optionee: Pierre Van Beneden
                  ------------------

Optionee's Social Security Number or Taxpayer ID Number:
                                                        --------------------

Number of Shares Covered by Option: 2,000,000
                                    -----------------

Exercise Price per Share: $1.13
                          -----------------

Vesting Start Date: October 8, 2001
                    ----------------

        BY SIGNING THIS COVER SHEET, YOU AGREE TO ALL OF THE TERMS AND
CONDITIONS DESCRIBED IN THE ATTACHED AGREEMENT AND IN THE PLAN, A COPY OF WHICH
IS ALSO ENCLOSED.

Optionee:      /s/ Pierre Van Beneden
                                       -----------------------------------
                                       (Signature)

Company:       /s/  William McGlashan
                                       -----------------------------------
                                       (Signature)

Title:  Interim Chief Executive Officer
                                       ---------------------------
Attachment


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                               CRITICAL PATH, INC.

                       1999 NONSTATUTORY STOCK OPTION PLAN

                       NONSTATUTORY STOCK OPTION AGREEMENT

NONSTATUTORY STOCK OPTION        This option is not intended to be an incentive
                                 stock option under section 422 of the Internal
                                 Revenue Code and will be interpreted
                                 accordingly.

VESTING COMMENCEMENT DATE        The Vesting Commencement Date on this option
                                 shall be October 9, 2001. Shares under this
                                 option will vest in accordance with the vesting
                                 schedule indicated below:

NUMBER OF OPTIONS                VESTING EVENT

        2,000,000                Monthly vesting beginning on the Vesting
                                 Commencement Date indicated above and continue
                                 all shares subject to this option shall be
                                 vested over the three (3) years following the
                                 issuance of this option.

                                 In the event your employment is terminated
                                 without cause by the Company prior to the one
                                 year anniversary of employment, or in the event
                                 you have not been offered the position of Chief
                                 Executive Officer.


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                                 Your option vesting will cease in the event
                                 that your employment and service as a Company
                                 director both terminate for any reason. Your
                                 option vesting will also cease upon your
                                 voluntary resignation of employment upon a
                                 termination for Cause (as such terms are
                                 defined in your employment agreement with the
                                 Company). A leave of absence, regardless of the
                                 reason, shall be deemed to constitute the
                                 cessation of your employment unless such leave
                                 is authorized by the Company, and you return
                                 within the time specified in such
                                 authorization.

                                 The Compensation Committee of the Board of
                                 Directors must certify in writing that the
                                 performance goals have been satisfied before
                                 any Option vesting will be accelerated pursuant
                                 to attainment of performance goals.

                                 In the event of a Change in Control of the
                                 Company, 50% of your then-unvested Options
                                 (meaning 50% of your unvested Options that are
                                 otherwise scheduled to vest under (ii), (iii)
                                 and (iv) above on each vesting date had a
                                 Change in Control not occurred) shall become
                                 vested provided that you are employed by the
                                 Company on the date the negotiations or
                                 communications began (as determined by the
                                 Board in good faith) which lead to the Change
                                 in Control provided, however, that all of your
                                 then-unvested Options shall become vested if
                                 the Change in Control consideration received by
                                 Company shareholders is at least $10.00 per
                                 share (with such share price adjusted for any
                                 future stock splits, stock dividends,
                                 recapitalization, or similar events).

TERM                             Your option will expire in any event at the
                                 close of business at Company headquarters on
                                 the day before the 10th anniversary of the Date
                                 of Grant, as shown on the cover sheet. It will
                                 expire earlier if your employment and your
                                 service as a Company director terminate, as
                                 described below.

REGULAR TERMINATION              If your employment and your service as a
                                 Company director terminate for any reason
                                 except Cause, death or Disability, then your
                                 option will expire at the close of business at
                                 Company headquarters on the 90th day after your
                                 termination date.

CAUSE                            If your employment or service as a Company
                                 director terminates on account of Cause, then
                                 your option will expire immediately.


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DEATH                            In the event of your death during the period of
                                 your employment or service as a Company
                                 director, your option will expire at the close
                                 of business at Company headquarters on the date
                                 six months after the date of death. During that
                                 six-month period, your estate or heirs may
                                 exercise your option.

DISABILITY                       If your employment and service as a Company
                                 director terminate because of your Disability,
                                 then your option will expire at the close of
                                 business at Company headquarters on the date
                                 six months after your termination date.

                                 "Disability" means that you are unable to
                                 engage in any substantial gainful activity by
                                 reason of any medically determinable physical
                                 or mental impairment.

LEAVES OF ABSENCE                For purposes of this option, your employment
                                 does not terminate when you go on a bona fide
                                 leave of absence, that was approved by the
                                 Company in writing, if the terms of the leave
                                 provide for continued service crediting, or
                                 when continued service crediting is required by
                                 applicable law. Your employment terminates in
                                 any event when the approved leave ends if you
                                 fail or refuse to return to active service.

                                 Consistent with the terms of this Agreement and
                                 your Employment Agreement, the Company
                                 determines which leaves count for this purpose,
                                 and when your employment terminates for all
                                 purposes under the Plan.

RESTRICTIONS ON EXERCISE         The Company will not permit you to exercise
                                 this option if the issuance of Shares at that
                                 time would violate any law or regulation.

NOTICE OF EXERCISE               When you wish to exercise this option, you must
                                 notify the Company by filing the proper "Notice
                                 of Exercise" form at the address given on the
                                 form. Your notice must specify how many Shares
                                 you wish to purchase. Your notice must also
                                 specify how your Shares should be registered
                                 (in your name only or in your and your spouse's
                                 names as community property or as joint tenants
                                 with right of survivorship). The notice will be
                                 effective when received by the Company.

                                 If someone else wants to exercise this option
                                 after your death, that person must prove to the
                                 Company's satisfaction that he or she is
                                 entitled to do so.

FORM OF PAYMENT                  When you submit your notice of exercise, you
                                 must include payment of the option price for
                                 the Shares you are purchasing.


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                                 Payment may be made in one (or a combination)
                                 of the following forms:

                                 -  Your personal check, a cashier's check or
                                    a money order.

                                 -  By delivery (on a form prescribed by the
                                    Committee) of an irrevocable direction to a
                                    securities broker to sell Shares and to
                                    deliver all or part of the sale proceeds to
                                    the Company in payment of the aggregate
                                    Exercise Price.

                                 -  Payment may be made all or in part with a
                                    full recourse promissory note executed by
                                    you. The interest rate and other terms and
                                    conditions of such note shall be determined
                                    in your employment agreement with the
                                    Company. The Company will require that you
                                    pledge your Shares to the Company for the
                                    purpose of securing the payment of such
                                    note.

WITHHOLDING TAXES                You will not be allowed to exercise this option
                                 unless you make acceptable arrangements to pay
                                 any withholding or other taxes that may be due
                                 as a result of the option exercise or the sale
                                 of the Shares acquired upon exercise of this
                                 option.

RESTRICTIONS ON RESALE           By signing this Agreement, you agree not to
                                 sell any option Shares at a time when
                                 applicable laws or regulations or Company or
                                 underwriter trading policies prohibit a sale.

                                 You represent and agree that the Shares to be
                                 acquired upon exercising this option will be
                                 acquired for investment, and not with a view to
                                 the sale or distribution thereof.

                                 In the event that the sale of Shares under the
                                 Plan is not registered under the Securities Act
                                 but an exemption is available which requires an
                                 investment representation or other
                                 representation, you shall represent and agree
                                 at the time of exercise to make such
                                 representations as are deemed necessary or
                                 appropriate by the Company and its counsel.

                                 Prior to any Change in Control of the Company,
                                 the shares acquired under this option can be
                                 sold or transferred only pursuant to an SEC
                                 Rule 10b5-1 trading plan that is pre-approved
                                 by the Board of Director's Compensation
                                 Committee.


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TRANSFER OF OPTION               Prior to your death, only you may exercise this
                                 option. You cannot transfer or assign this
                                 option. For instance, you may not sell this
                                 option or use it as security for a loan. If you
                                 attempt to do any of these things, this option
                                 will immediately become invalid. You may,
                                 however, dispose of this option in your will.

                                 Regardless of any marital property settlement
                                 agreement, the Company is not obligated to
                                 honor a notice of exercise from your spouse or
                                 former spouse, nor is the Company obligated to
                                 recognize such individual's interest in your
                                 option in any other way.

NO RETENTION RIGHTS              Your option or this Agreement do not give you
                                 the right to be retained by the Company (or any
                                 subsidiaries) in any capacity. The Company (and
                                 any subsidiaries) reserves the right to
                                 terminate your Service at any time and for any
                                 reason.

SHAREHOLDER RIGHTS               You, or your estate or heirs, have no rights as
                                 a shareholder of the Company until a
                                 certificate for your option Shares has been
                                 issued. No adjustments are made for dividends
                                 or other rights if the applicable record date
                                 occurs before your stock certificate is issued,
                                 except as described in the Plan.

ADJUSTMENTS                      In the event of a stock split, a stock dividend
                                 or a similar change in the Company stock, the
                                 number of Shares covered by this option and the
                                 exercise price per share may be adjusted
                                 pursuant to the Plan. Your option shall be
                                 subject to the terms of the agreement of
                                 merger, liquidation or reorganization in the
                                 event the Company is subject to such corporate
                                 activity, except to the extent the foregoing
                                 conflict with or are in any way inconsistent
                                 with Section 8 of your employment agreement.


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FORFEITURE                       If, at any time within one year after
                                 termination of employment, you engage in any of
                                 the following: (i) your commission of a felony,
                                 an act involving moral turpitude, or an act
                                 constituting common law fraud, in each case
                                 having a material adverse effect on the
                                 business or affairs of the Company or its
                                 affiliates or stockholders; (ii) your willful
                                 or intentional breach of Company confidential
                                 information obligations, in each case having a
                                 material adverse effect on the business or
                                 affairs of the Company or its affiliates or
                                 stockholders; or (iii) your unreasonable
                                 refusal to comply with lawful requests for
                                 cooperation made by the Board of Directors,
                                 then (1) this option shall terminate and be
                                 forfeited effective the date on which you enter
                                 into such activity, unless terminated or
                                 forfeited sooner by operation of another term
                                 or condition of this option or the Plan, (2)
                                 any stock acquired by you pursuant to the
                                 exercise of this option during the Forfeiture
                                 Period (as defined below) shall be forfeited,
                                 and (3) any gain realized by you from the sale
                                 of stock acquired through the exercise of this
                                 option during the Forfeiture Period shall be
                                 paid by you to the Company. The "Forfeiture
                                 Period" shall mean the period commencing six
                                 months prior to your termination of employment
                                 and ending one year from your termination of
                                 employment.

RIGHT OF SET OFF                 By accepting this Agreement, you consent to a
                                 deduction from any amounts the Company owes you
                                 from time to time, to the extent of the amounts
                                 you owe the Company under the paragraph above.
                                 If the Company does not recover by means of
                                 set-off the full amount you owe it, calculated
                                 as set forth above, you agree to pay
                                 immediately the unpaid balance to the Company
                                 upon the Company's demand.

LEGENDS                          All certificates representing the Shares issued
                                 upon exercise of this option shall have
                                 endorsed thereon the applicable legends.

APPLICABLE LAW                   This Agreement will be interpreted and enforced
                                 under the laws of the State of California.

THE PLAN AND OTHER AGREEMENTS    The text of the Plan and your employment
                                 agreement are incorporated in this Agreement by
                                 reference. Certain capitalized terms used in
                                 this Agreement are defined in the Plan or your
                                 employment agreement.


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                                 This Agreement, the Plan and your employment
                                 agreement with the Company dated October 8,
                                 2001 constitute the entire understanding
                                 between you and the Company regarding this
                                 option. Any prior agreements, commitments or
                                 negotiations concerning this option are
                                 superseded.

BY SIGNING THE COVER SHEET OF THIS AGREEMENT, YOU AGREE TO ALL OF THE TERMS AND
CONDITIONS DESCRIBED ABOVE AND IN THE PLAN, EXCEPT TO THE EXTENT MODIFIED BY
YOUR EMPLOYMENT AGREEMENT WITH THE COMPANY.