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                                                                     EXHIBIT 4.3









                               CRITICAL PATH, INC.

                          EMPLOYEE STOCK PURCHASE PLAN



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                                TABLE OF CONTENTS



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Section 1.  Establishment of the Plan........................................................1

Section 2.  Definitions......................................................................1

Section 3.  Shares Authorized................................................................2

Section 4.  Administration...................................................................2

Section 5.  Eligibility and Participation....................................................2

Section 6.  Participation and Purchase Periods...............................................3

Section 7.  Purchase Price...................................................................3

Section 8.  Employee Contributions...........................................................3

Section 9.  Plan Accounts; Purchase of Shares................................................4

Section 10. Withdrawal From the Plan.........................................................4

Section 11. Effect of Termination of Employment or Death.....................................5

Section 12. Rights Not Transferable..........................................................5

Section 13. Recapitalization, Etc............................................................5

Section 14. Limitation on Stock Ownership....................................................6

Section 15. No Rights as an Employee.........................................................6

Section 16. Rights as a Shareholder..........................................................6

Section 17. Use of Funds.....................................................................6

Section 18. Amendment or Termination of the Plan.............................................6

Section 19. Governing Law....................................................................6
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                               CRITICAL PATH, INC.

                          EMPLOYEE STOCK PURCHASE PLAN


Section 1. Establishment of the Plan.

        The Critical Path, Inc. Employee Stock Purchase Plan (the "Plan") is
hereby established to provide Eligible Employees with an opportunity to purchase
the Company's Common Stock so that they may increase their equity interest in
and share in the success of the Company. The Plan, which provides for the
purchase of stock through payroll withholding, is intended to qualify under
Section 423 of the Code.


Section 2. Definitions.

        (a) "Board of Directors" or "Board" means the Board of Directors of the
Company.

        (b) "Code" means the Internal Revenue Code of 1986, as amended.

        (c) "Company" means Critical Path, Inc., a California corporation.

        (d) "Compensation" means the base compensation paid to a Participant
during a Participation Period in cash or in kind, excluding overtime,
commissions, shift differentials and other forms of compensation for work
outside the regular work schedule.

        (e) "Date of Participation" means the first day of a Participation
Period.

        (f) "Eligible Employee" means any Employee of a Participating Company
(i) whose customary employment is for more than five months per calendar year
and for more than 20 hours per week and (ii) who is an Employee at the
commencement of a Participation Period.

        (g) "Employee" means any common-law employee of a Participating Company.

        (h) "Fair Market Value" shall mean (i) the closing price of a share of
Stock on the principal exchange which the shares are trading on the first
trading day immediately preceding the date on which the Fair Market Value is
determined, or (ii) if the shares are not traded on an exchange but are traded
or quoted on the Nasdaq National Market or a successor quotation system, the
closing price on the Nasdaq National Market or such successor quotation system
on the first trading day immediately preceding the date on which the Fair Market
Value is determined, or (iii) if the shares are not traded on an exchange or
quoted on the Nasdaq National Market or a successor quotation system, the fair
market value of a share as determined by the Plan Administrator in good faith.
Such determination shall be conclusive and binding on all persons.

        (i) "Participant" means an Eligible Employee who elects to participate
in the Plan, as provided in Section 5 hereof.

        (j) "Participating Company" means the Company and such present or future
Subsidiaries of the Company as the Board of Directors shall from time to time
designate.




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        (k) "Participation Period" means a period during which the right to
purchase Stock may be granted under the Plan, as determined pursuant to Section
6.

        (l) "Plan Account" means the account established for each Participant
pursuant to Section 9(a).

        (m) "Purchase Period" means a period during which contributions may be
made toward the purchase of Stock under the Plan, as determined pursuant to
Section 6.

        (n) "Purchase Price" means the price at which Participants may purchase
Stock under Section 5 of the Plan, as determined pursuant to Section 7.

        (o) "Stock" means the Common Stock of the Company.

        (p) "Subsidiary" means a subsidiary corporation as defined in Section
424 of the Code.


Section 3. Shares Authorized.

        The maximum aggregate number of shares which may be offered under the
Plan shall be 600,000 (post 2.2:1 reverse stock split effective in March 1999)
shares of Stock, plus an additional number of shares each January 1 equal to 1%
of the Company's issued and outstanding Stock, up to a maximum of 1,000,000
(post 2.2:1 reverse stock split effective in March 1999) additional shares of
Stock, all of which numbers are subject to adjustment as provided in Section 13
hereof.


Section 4. Administration.

        (a) The Plan shall be administered by a Plan Administrator appointed by
the Board of Directors. In the absence of such an appointment, the full Board of
Directors shall serve as the Plan Administrator. The interpretation and
construction by the Plan Administrator of any provision of the Plan or of any
right to purchase stock qualified hereunder shall be conclusive and binding on
all persons.

        (b) All costs and expenses incurred in administering the Plan shall be
paid by the Company. The Board or the Plan Administrator may request advice for
assistance or employ such other persons as are necessary for proper
administration of the Plan. A Participant who withdraws from the Plan in
accordance with Section 10 may again become a Participant, if he or she then is
an Eligible Employee, by following the procedure described in Section 5(a).


Section 5. Eligibility and Participation.

        (a) Any person who qualifies or will qualify as an Eligible Employee on
the Date of Participation with respect to a Participation Period may elect to
participate in the Plan for such Participation Period. An Eligible Employee may
elect to participate by executing the participation agreement prescribed for
such purpose by the Plan Administrator. The participation agreement shall be
filed with the Plan Administrator no later than the deadline stated on the
participation agreement, and if none is stated, then no later than the first day
of the Participation Period. The Eligible Employee shall designate on the
participation agreement the percentage of




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his or her Compensation which he or she elects to have withheld for the purchase
of Stock, which may be any whole percentage of the Participant's Compensation or
fixed dollar amount specified by the Plan Administrator.

        (b) By enrolling in the Plan, a Participant shall be deemed to have
elected to purchase the maximum number of whole shares of Stock which can be
purchased with the amount of the Participant's Compensation which is withheld
during the Purchase Period, subject to any limitations imposed by the Plan
Administrator pursuant to Section 6, and/or Section 14.

        (c) Once enrolled, a Participant will continue to participate in the
Plan for each succeeding Purchase Period until he or she terminates
participation or ceases to qualify as an Eligible Employee. A Participant who
withdraws from the Plan in accordance with Section 10 may again become a
Participant, if he or she then is an Eligible Employee, by following the
procedure described in Section 5(a).

Section 6.     Participation and Purchase Periods.

        The Plan shall be implemented by one or more Participation Periods of
not more than twenty-seven (27) months each. The Plan Administrator shall
determine the commencement date and duration of each Participation Period, the
number and duration of Purchase Periods within a Participation Period, the
purchase dates, and the maximum number of shares that may be purchased by a
Participant during the Participation Period.


Section 7. Purchase Price.

        The Purchase Price for each share of Stock shall be the lesser of (i)
eighty-five percent (85%) of the Fair Market Value of such share on the Date of
Participation or (ii) eighty-five percent (85%) of the Fair Market Value of such
share on the last trading day prior to the applicable purchase date.


Section 8. Employee Contributions.

        A Participant may purchase shares of Stock solely by means of payroll
deductions. Payroll deductions, as designated by the Participant pursuant to
Section 5(a), shall commence with the first paycheck issued during the
Participation Period and shall be deducted from each subsequent paycheck
throughout the Participation Period. If a Participant desires to decrease the
rate of payroll withholding during the Participation Period, he or she may do
so, if permitted by the Plan Administrator, by filing a new participation
agreement with the Plan Administrator. Such decrease will be effective as of the
date prescribed by the Company following the receipt of the new participation
agreement. If a Participant desires to increase the rate of payroll withholding,
he or she may do so effective for the next Participation Period by filing a new
participation agreement with the Plan Administrator on or before the date
specified by the Plan Administrator, and if none is stated, then no later than
the first day of the Participation Period for which such change is to be
effective.




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Section 9. Plan Accounts; Purchase of Shares.

        (a) The Company will maintain a non-interest bearing Plan Account on its
books in the name of each Participant. At the close of each pay period, the
amount deducted from the Participant's Compensation will be credited to the
Participant's Plan Account.

        (b) As of the last day of each Purchase Period, the amount then in the
Participant's Plan Account will be divided by the Purchase Price, and the number
of whole shares which results (subject to the limitations described in Sections
5(b), 9(c) and 14) shall be purchased from the Company with the funds in the
Participant's Plan Account. Following the purchase of the shares, the shares
will be electronically delivered to a brokerage account for the benefit of the
Participant, unless the Participant elects that certificates for the shares
shall be delivered to the Participant as provided in the election form
prescribed by the Company.

        (c) In the event that the aggregate number of shares which all
Participants elect to purchase during a Purchase Period shall exceed the number
of shares remaining available for issuance under the Plan, then the number of
shares to which each Participant shall become entitled shall be determined by
multiplying the number of shares available for issuance by a fraction the
numerator of which is the sum of the number of shares the Participant has
elected to purchase pursuant to Section 5, and the denominator of which is the
sum of the number of shares which all employees have elected to purchase
pursuant to Section 5. Any cash amount remaining in the Participant's Plan
Account under these circumstances shall be refunded to the Participant.

        (d) Any amount remaining in the Participant's Plan Account caused by a
surplus due to fractional shares after deducting the amount of the Purchase
Price for the number of whole shares issued to the Participant shall be carried
over in the Participant's Plan Account for the succeeding Purchase Period,
without interest. Any amount remaining in the Participant's Plan Account caused
by anything other than a surplus due to fractional shares shall be refunded to
the Participant in cash, without interest.

        (e) As soon as practicable following the end of each Purchase Period,
the Company shall deliver to each Participant a Plan Account statement setting
forth the amount of payroll deductions, the purchase price, the number of shares
purchased and the remaining cash balance, if any.


Section 10. Withdrawal From the Plan.

        A Participant may elect to withdraw from participation under the Plan at
any time up to the 15th day of the last month of a Purchase Period by filing the
prescribed form with the Plan Administrator. As soon as practicable after a
withdrawal, payroll deductions shall cease and all amounts credited to the
Participant's Plan Account will be refunded in cash, without interest. A
Participant who has withdrawn from the Plan shall not be a Participant in future
Participation Periods, unless he or she again enrolls in accordance with the
provisions of Section 5.




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Section 11.    Effect of Termination of Employment or Death.

        (a) Termination of employment as an Eligible Employee for any reason,
including death, shall be treated as an automatic withdrawal from the Plan under
Section 10. A transfer from one Participating Company to another shall not be
treated as a termination of employment.

        (b) A Participant may file a written designation of a beneficiary who is
to receive any shares and cash, if any, from the Participant's Account under the
Plan in the event of such Participant's death subsequent to the purchase of
shares but prior to delivery to him of such shares and cash. In addition, a
Participant may file a written designation of a beneficiary who is to receive
any cash from the Participant's Account under the Plan in the event of such
Participant's death prior to the last day of a Participation Period.

        (c) Such designation of beneficiary may be changed by the Participant at
any time by written notice. In the event of the death of a Participant in the
absence of a valid designation of a beneficiary who is living at the time of
such Participant's death, the Company shall deliver such shares and/or cash to
the executor or administrator of the estate of the Participant; or if no such
executor or administrator has been appointed (to the knowledge of the Company),
the Company, in its discretion, may deliver such shares and/or cash to the
spouse or to any one or more dependents or relatives of the Participant; or if
no spouse, dependent or relative is known to the Company, then to such other
person as the Company may designate.


Section 12. Rights Not Transferable.

        The rights or interests of any Participant in the Plan, or in any Stock
or moneys to which he or she may be entitled under the Plan, shall not be
transferable by voluntary or involuntary assignment or by operation of law, or
by any other manner other than as permitted by the Code or by will or the laws
of descent and distribution. If a Participant in any manner attempts to
transfer, assign or otherwise encumber his or her rights or interest under the
Plan, other than as permitted by the Code or by will or the laws of descent and
distribution, such act shall be treated as an automatic withdrawal under Section
10.


Section 13. Recapitalization, Etc.

        (a) The aggregate number of shares of Stock offered under the Plan, the
number and price of shares which any Participant has elected to purchase
pursuant to Section 5 and the maximum number of shares which a Participant may
elect to purchase under the Plan in any Participation Period shall be
proportionately adjusted for any increase or decrease in the number of issued
shares of Stock resulting from a subdivision or consolidation of shares or any
other capital adjustment, the payment of a stock dividend, or other increase or
decrease in such shares effected without receipt of consideration by the
Company.

        (b) In the event of a dissolution or liquidation of the Company, or a
merger or consolidation to which the Company is a constituent corporation, this
Plan shall terminate, unless the plan of merger, consolidation or reorganization
provides otherwise, and all amounts which each Participant has paid towards the
Purchase Price of Stock hereunder shall be refunded, without interest.




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        (c) The Plan shall in no event be construed to restrict in any way the
Company's right to undertake a dissolution, liquidation, merger, consolidation
or other reorganization.


Section 14. Limitation on Stock Ownership.

        Notwithstanding any provision herein to the contrary, no Participant
shall be permitted to elect to participate in the Plan (i) if such Participant,
immediately after his or her election to participate, would own stock possessing
five percent (5%) or more of the total combined voting power or value of all
classes of stock of the Company or any parent or Subsidiary of the Company, or
(ii) if under the terms of the Plan the rights of the Employee to purchase Stock
under this Plan and all other qualified employee stock purchase plans of the
Company or its Subsidiaries would accrue at a rate which exceeds twenty-five
thousand dollars ($25,000) of the Fair Market Value of such Stock (determined at
the time such right is granted) for each calendar year for which such right is
outstanding at any time. For purposes of this Section 14, ownership of stock
shall be determined by the attribution rules of Section 424(d) of the Code, and
Participants shall be considered to own any stock which they have a right to
purchase under this or any other stock plan.


Section 15. No Rights as an Employee.

        Nothing in the Plan shall be construed to give any person the right to
remain in the employ of a Participating Company. Each Participating Company
reserves the right to terminate the employment of any person at any time and for
any reason.


Section 16. Rights as a Shareholder.

        A Participant shall have no rights as a shareholder with respect to any
shares he or she may have a right to purchase under the Plan until the date such
shares are actually purchased for the Participant's account, subject to the
shareholders' approval of the adoption of the Plan.


Section 17. Use of Funds.

        All payroll deductions received or held by the Company under the Plan
may be used by the Company for any corporate purpose, and the Company shall not
be obligated to segregate such payroll deductions in separate accounts.


Section 18. Amendment or Termination of the Plan.

        The Board of Directors shall have the right to amend, modify or
terminate the Plan at any time without notice. An amendment of the Plan shall be
subject to shareholder approval only to the extent required by applicable laws,
regulations or rules.


Section 19. Governing Law.

        The Plan shall be governed by, and construed and interpreted in
accordance with, the laws of the State of California.




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