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                                                                    EXHIBIT 10.5

                                VALICERT, INC.
                       2000 EMPLOYEE STOCK PURCHASE PLAN

     1.   Establishment, Purpose and Term of Plan.
          ---------------------------------------

          1.1  Establishment. The ValiCert, Inc. 2000 Employee Stock Purchase
Plan (the "Plan") is hereby established effective as of the effective date of
the initial registration by the Company of its Stock under Section 12 of the
Securities Exchange Act of 1934, as amended (the "Effective Date").

          1.2  Purpose. The purpose of the Plan is to advance the interests of
Company and its stockholders by providing an incentive to attract and retain
Eligible Employees of the Participating Company Group and by motivating such
persons to contribute to the growth and profitability of the Participating
Company Group. The Plan provides such Eligible Employees with an opportunity to
acquire a proprietary interest in the Company through the purchase of Stock. The
Company intends that the Plan qualify as an "employee stock purchase plan" under
Section 423 of the Code (including any amendments or replacements of such
section), and the Plan shall be so construed.

          1.3  Term of Plan. The Plan shall continue in effect until the earlier
of its termination by the Board or the date on which all of the shares of Stock
available for issuance under the Plan have been issued.

     2.   Definitions and Construction.
          ----------------------------

          2.1  Definitions. Any term not expressly defined in the Plan but
defined for purposes of Section 423 of the Code shall have the same definition
herein. Whenever used herein, the following terms shall have their respective
meanings set forth below:

               (a)  "Board" means the Board of Directors of the Company. If one
or more Committees have been appointed by the Board to administer the Plan,
"Board" also means such Committee(s).

               (b)  "Code" means the Internal Revenue Code of 1986, as amended,
and any applicable regulations promulgated thereunder.

               (c)  "Committee" means a committee of the Board duly appointed to
administer the Plan and having such powers as specified by the Board. Unless the
powers of the Committee have been specifically limited, the Committee shall have
all of the powers of the Board granted herein, including, without limitation,
the power to amend or terminate the Plan at any time, subject to the terms of
the Plan and any applicable limitations imposed by law.

               (d)  "Company" means ValiCert, Inc., a Delaware corporation, or
any successor corporation thereto.

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               (e)  "Compensation" means, with respect to any Offering Period,
base wages or salary, overtime pay, bonuses, commissions, shift differentials,
payments for paid time off, payments in lieu of notice, and any of such
compensation deferred under any program or plan established by a Participating
Company, including, without limitation, pursuant to Section 401(k) or Section
125 of the Code. Compensation shall be limited to amounts actually payable in
cash directly to the Participant or deferred by the Participant during the
Offering Period. However, notwithstanding the foregoing, Compensation shall not
include sign-on bonuses, payments pursuant to a severance agreement, termination
pay, reimbursements of expenses, allowances, disability pay, workers'
compensation or any amount deemed received without the actual transfer of cash
or any amounts directly or indirectly paid pursuant to the Plan or any other
stock purchase or stock option plan, or any other compensation not included
above.

               (f)  "Eligible Employee" means an Employee who meets the
requirements set forth in Section 5 for eligibility to participate in the Plan.

               (g)  "Employee" means a person treated as an employee of a
Participating Company for purposes of Section 423 of the Code. A Participant
shall be deemed to have ceased to be an Employee either upon an actual
termination of employment or upon the corporation employing the Participant
ceasing to be a Participating Company. For purposes of the Plan, an individual
shall not be deemed to have ceased to be an Employee while on any military
leave, sick leave, or other bona fide leave of absence approved by the Company
of ninety (90) days or less. If an individual's leave of absence exceeds ninety
(90) days, the individual shall be deemed to have ceased to be an Employee on
the ninety-first (91st) day of such leave unless the individual's right to
reemployment with the Participating Company Group is guaranteed either by
statute or by contract. The Company shall determine in good faith and in the
exercise of its discretion whether an individual has become or has ceased to be
an Employee and the effective date of such individual's employment or
termination of employment, as the case may be. For purposes of an individual's
participation in or other rights, if any, under the Plan as of the time of the
Company's determination, all such determinations by the Company shall be final,
binding and conclusive, notwithstanding that the Company or any governmental
agency subsequently makes a contrary determination.

               (h)  "Entry Date" means (i) the Offering Date of an Offering
Period, or (ii) with respect to persons who first become Eligible Employees
after the commencement of the Initial Offering Period (as defined in Section 6.1
below) but prior to the commencement of the final Purchase Period of the Initial
Offering Period, or did not previously elect to participate in the Initial
Offering Period, the first day of the Purchase Period following the date on
which such person becomes an Eligible Employee, or elects to enroll in the
Initial Offering Period, respectively. Notwithstanding the foregoing, in the
event that the Fair Market Value of a share of Stock on the first, second or
third Purchase Date of the Initial Offering Period is less than the Fair Market
Value of a share of Stock on the Entry Date for a Participant who was
participating in the Offering as of such Purchase Date, the Entry Date for such
Participant for the remainder of the Offering shall be the first day of the next
Purchase Period immediately following such Purchase Date.

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               (i)  "Fair Market Value" means, as of any date:

                    (i)     If the Stock is then listed on a national or
regional securities exchange or market system or is regularly quoted by a
recognized securities dealer, the closing sale price of a share of Stock (or the
mean of the closing bid and asked prices if the Stock is so quoted instead) as
quoted on the Nasdaq National Market, the Nasdaq SmallCap Market or such other
national or regional securities exchange or market system constituting the
primary market for the Stock, or by such recognized securities dealer, as
reported in The Wall Street Journal or such other source as the Company deems
            -----------------------
reliable. If the relevant date does not fall on a day on which the Stock has
traded on such securities exchange or market system or has been quoted by such
securities dealer, the date on which the Fair Market Value is established shall
be the last day on which the Stock was so traded or quoted prior to the relevant
date, or such other appropriate day as determined by the Board, in its
discretion.

                    (ii)    If, on the relevant date, the Stock is not then
listed on a national or regional securities exchange or market system or
regularly quoted by a recognized securities dealer, the Fair Market Value of a
share of Stock shall be as determined in good faith by the Board.

                    (iii)   Notwithstanding the foregoing, the Fair Market Value
of a share of Stock on the Effective Date shall be deemed to be the public
offering price set forth in the final prospectus filed with the Securities and
Exchange Commission in connection with the Company's initial public offering of
the Stock.

               (j)  "Offering" means an offering of Stock as provided in Section
6.

               (k)  "Offering Date" means, for any Offering, the first day of
the Offering Period.

               (l)  "Offering Period" means a period established in accordance
with Section 6.1.

               (m)  "Parent Corporation" means any present or future "parent
corporation" of the Company, as defined in Section 424(e) of the Code.

               (n)  "Participant" means an Eligible Employee who has become a
participant in an Offering Period in accordance with Section 7 and remains a
participant in accordance with the Plan.

               (o)  "Participating Company" means the Company or any Parent
Corporation or Subsidiary Corporation designated by the Board as a corporation
the Employees of which may, if Eligible Employees, participate in the Plan. The
Board shall have the sole and absolute discretion to determine from time to time
which Parent Corporations or Subsidiary Corporations shall be Participating
Companies.

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               (p)  "Participating Company Group" means, at any point in time,
the Company and all other corporations collectively which are then Participating
Companies.

               (q)  "Purchase Date" means, for any Purchase Period, the last day
of such period.

               (r)  "Purchase Period" means a period established in accordance
with Section 6.2.

               (s)  "Purchase Price" means the price at which a share of Stock
may be purchased under the Plan, as determined in accordance with Section 9.

               (t)  "Purchase Right" means an option granted to a Participant
pursuant to the Plan to purchase such shares of Stock as provided in Section 8,
which the Participant may or may not exercise during the Offering Period in
which such option is outstanding. Such option arises from the right of a
Participant to withdraw any accumulated payroll deductions of the Participant
not previously applied to the purchase of Stock under the Plan and to terminate
participation in the Plan at any time during an Offering Period.

               (u)  "Stock" means the common stock of the Company, as adjusted
from time to time in accordance with Section 4.2.

               (v)  "Subscription Agreement" means a written agreement in such
form as specified by the Company, stating an Employee's election to participate
in the Plan and authorizing payroll deductions under the Plan from the
Employee's Compensation.

               (w)  "Subscription Date" means the last business day prior to an
Entry Date or such other date as the Company shall establish.

               (x)  "Subsidiary Corporation" means any present or future
"subsidiary corporation" of the Company, as defined in Section 424(f) of the
Code.

          2.2  Construction. Captions and titles contained herein are for
convenience only and shall not affect the meaning or interpretation of any
provision of the Plan. Except when otherwise indicated by the context, the
singular shall include the plural and the plural shall include the singular. Use
of the term "or" is not intended to be exclusive, unless the context clearly
requires otherwise.

     3.   Administration.
          --------------

          3.1  Administration by the Board. The Plan shall be administered by
the Board. All questions of interpretation of the Plan, of any form of agreement
or other document employed by the Company in the administration of the Plan, or
of any Purchase Right shall be determined by the Board and shall be final and
binding upon all persons having an interest in the Plan or the Purchase Right.
Subject to the provisions of the Plan, the Board shall determine all of the
relevant terms and conditions of Purchase Rights; provided, however, that all
Participants

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granted Purchase Rights pursuant to an Offering shall have the same rights and
privileges within the meaning of Section 423(b)(5) of the Code. All expenses
incurred in connection with the administration of the Plan shall be paid by the
Company.

          3.2  Authority of Officers. Any officer of the Company shall have the
authority to act on behalf of the Company with respect to any matter, right,
obligation, determination or election that is the responsibility of or that is
allocated to the Company herein, provided that the officer has apparent
authority with respect to such matter, right, obligation, determination or
election.

          3.3  Policies and Procedures Established by the Company. The Company
may, from time to time, consistent with the Plan and the requirements of Section
423 of the Code, establish, change or terminate such rules, guidelines,
policies, procedures, limitations, or adjustments as deemed advisable by the
Company, in its discretion, for the proper administration of the Plan,
including, without limitation, (a) a minimum payroll deduction amount required
for participation in an Offering, (b) a limitation on the frequency or number of
changes permitted in the rate of payroll deduction during an Offering, (c) an
exchange ratio applicable to amounts withheld in a currency other than United
States dollars, (d) a payroll deduction greater than or less than the amount
designated by a Participant in order to adjust for the Company's delay or
mistake in processing a Subscription Agreement or in otherwise effecting a
Participant's election under the Plan or as advisable to comply with the
requirements of Section 423 of the Code, and (e) determination of the date and
manner by which the Fair Market Value of a share of Stock is determined for
purposes of administration of the Plan.

          3.4  Indemnification. In addition to such other rights of
indemnification as they may have as members of the Board or officers or
employees of the Participating Company Group, members of the Board and any
officers or employees of the Participating Company Group to whom authority to
act for the Board or the Company is delegated shall be indemnified by the
Company against all reasonable expenses, including attorneys' fees, actually and
necessarily incurred in connection with the defense of any action, suit or
proceeding, or in connection with any appeal therein, to which they or any of
them may be a party by reason of any action taken or failure to act under or in
connection with the Plan, or any right granted hereunder, and against all
amounts paid by them in settlement thereof (provided such settlement is approved
by independent legal counsel selected by the Company) or paid by them in
satisfaction of a judgment in any such action, suit or proceeding, except in
relation to matters as to which it shall be adjudged in such action, suit or
proceeding that such person is liable for gross negligence, bad faith or
intentional misconduct in duties; provided, however, that within sixty (60) days
after the institution of such action, suit or proceeding, such person shall
offer to the Company, in writing, the opportunity at its own expense to handle
and defend the same.

     4.   Shares Subject to Plan.
          ----------------------

          4.1 Maximum Number of Shares Issuable. Subject to adjustment as
provided in Section 4.2, the maximum aggregate number of shares of Stock that
may be issued under the Plan shall be 1,000,000, cumulatively increased on
January 1, 2001 and each January 1 thereafter until and including January 1,
2010 (the "Annual Increase") by the lesser of (a) 2%

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of the shares of issued and outstanding Stock on the immediately preceding
December 31, (b) ____________ shares, or (c) such lesser number of shares
determined by the Board, and shall consist of authorized but unissued or
reacquired shares of Stock, or any combination thereof. If an outstanding
Purchase Right for any reason expires or is terminated or canceled, the shares
of Stock allocable to the unexercised portion of that Purchase Right shall again
be available for issuance under the Plan.

          4.2  Adjustments for Changes in Capital Structure. In the event of any
stock dividend, stock split, reverse stock split, recapitalization, combination,
reclassification or similar change in the capital structure of the Company, or
in the event of any merger (including a merger effected for the purpose of
changing the Company's domicile), sale of assets or other reorganization in
which the Company is a party, appropriate adjustments shall be made in the
number and class of shares subject to the Plan, the Annual Increase, the limit
on the shares which may be purchased by any Participant on a Purchase Date (as
described in Section 8.1) and each Purchase Right, and in the Purchase Price. If
a majority of the shares of the same class as the shares subject to outstanding
Purchase Rights are exchanged for, converted into, or otherwise become (whether
or not pursuant to an Ownership Change Event) shares of another corporation (the
"New Shares"), the Board may unilaterally amend the outstanding Purchase Rights
to provide that such Purchase Rights are exercisable for New Shares. In the
event of any such amendment, the number of shares subject to, and the Purchase
Price of, the outstanding Purchase Rights shall be adjusted in a fair and
equitable manner, as determined by the Board, in its discretion. Notwithstanding
the foregoing, any fractional share resulting from an adjustment pursuant to
this Section 4.2 shall be rounded down to the nearest whole number, and in no
event may the Purchase Price be decreased to an amount less than the par value,
if any, of the stock subject to the Purchase Right. The adjustments determined
by the Board pursuant to this Section 4.2 shall be final, binding and
conclusive.

     5.   Eligibility.
          -----------

          5.1  Employees Eligible to Participate. Each Employee of a
Participating Company is eligible to participate in the Plan and shall be deemed
an Eligible Employee, except any Employee who is either: (a) customarily
employed by the Participating Company Group for twenty (20) hours or less per
week or (b) customarily employed by the Participating Company Group for not more
than five (5) months in any calendar year.

          5.2  Exclusion of Certain Stockholders. Notwithstanding any provision
of the Plan to the contrary, no Employee shall be granted a Purchase Right under
the Plan if, immediately after such grant, the Employee would own or hold
options to purchase stock of the Company or of any Parent Corporation or
Subsidiary Corporation possessing five percent (5%) or more of the total
combined voting power or value of all classes of stock of such corporation, as
determined in accordance with Section 423(b)(3) of the Code. For purposes of
this Section 5.2, the attribution rules of Section 424(d) of the Code shall
apply in determining the stock ownership of such Employee.

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     6.   Offerings.
          ---------

          6.1  Offering Periods.

               (a)  Initial Offering Period. The Plan shall be implemented by
sequential Offerings (an "Offering Period"). The first Offering Period shall
commence on the Effective Date and end on the last day of July, 2002 (the
"Initial Offering Period").

               (b)  Subsequent Offering Periods. After the completion of the
Initial Offering Period, subsequent Offerings shall commence on the first day of
February and August of each year and end on the last day of July and January,
respectively, occurring thereafter, and will have a duration of approximately
six (6) months.

          6.2  Purchase Periods. The Initial Offering Period shall consist of
four (4) consecutive Purchase Periods of approximately six (6) months duration.
Purchase Periods shall commence on the Effective Date, February 1, 2001, August
1, 2001 and February 1, 2002. Purchase Periods beginning on the first day of
February and August shall end on the last day of July and January, respectively,
occurring thereafter. The Purchase Period commencing on the Effective Date shall
end on January 31, 2001.

          6.3  Discretion to Vary Duration. Notwithstanding the foregoing, the
Board may establish a different duration for one or more Offering Periods or
Purchase Periods or different commencing or ending dates for such periods;
provided, however, that no Offering Period may have a duration exceeding twenty-
seven (27) months. If the first or last day of an Offering Period or a Purchase
Period is not a day on which the national securities exchanges or Nasdaq Stock
Market are open for trading, the Company shall specify the trading day that will
be deemed the first or last day, as the case may be, of the period.

     7.   Participation in the Plan.
          -------------------------

          7.1  Initial Participation. An Eligible Employee may become a
Participant in an Offering Period by delivering a properly completed
Subscription Agreement to the office designated by the Company not later than
the close of business for such office on the Subscription Date established by
the Company for the applicable Entry Date. An Eligible Employee who does not
deliver a properly completed Subscription Agreement to the Company's designated
office on or before the Subscription Date for an Entry Date shall not
participate in the Plan for that Offering Period or for any subsequent Offering
Period unless the Eligible Employee subsequently delivers a properly completed
Subscription Agreement to the appropriate office of the Company on or before the
Subscription Date for a subsequent Entry Date. An Employee who becomes an
Eligible Employee after the Offering Date of an Offering Period (other than the
Initial Offering Period) shall not be eligible to participate in that Offering
Period but may participate in any subsequent Offering Period provided the
Employee is still an Eligible Employee as of the Offering Date of such
subsequent Offering Period.

          7.2  Continued Participation. A Participant shall automatically
participate in the next Offering Period commencing immediately after the final
Purchase Date of each Offering

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Period in which the Participant participates provided that the Participant
remains an Eligible Employee on the Offering Date of the new Offering Period and
has not either (a) withdrawn from the Plan pursuant to Section 12.1 or (b)
terminated employment as provided in Section 13. A Participant who may
automatically participate in a subsequent Offering Period, as provided in this
Section, is not required to deliver any additional Subscription Agreement for
the subsequent Offering Period in order to continue participation in the Plan.
However, a Participant may deliver a new Subscription Agreement for a subsequent
Offering Period in accordance with the procedures set forth in Section 7.1 if
the Participant desires to change any of the elections contained in the
Participant's then effective Subscription Agreement.

     8.   Right to Purchase Shares.
          ------------------------

          8.1  Grant of Purchase Right.  Except as set forth below (or otherwise
specified by the Board prior to the Offering Date), on the Offering Date of each
Offering Period, each Participant in such Offering Period shall be granted
automatically, on his or her Entry Date, a Purchase Right consisting of an
option to purchase, on each Purchase Date within such Offering Period, that
number of whole shares of Stock determined by dividing the aggregate payroll
deductions collected from the Participant by the applicable Purchase Price on
such Purchase Date; provided, however, that no Participant may purchase more
than 7,500 shares of Stock on any Purchase Date.

          8.2  Calendar Year Purchase Limitation. Notwithstanding any provision
of the Plan to the contrary, no Participant shall be granted a Purchase Right
which permits his or her right to purchase shares of Stock under the Plan to
accrue at a rate which, when aggregated with such Participant's rights to
purchase shares under all other employee stock purchase plans of a Participating
Company intended to meet the requirements of Section 423 of the Code, exceeds
Twenty-Five Thousand Dollars ($25,000) in Fair Market Value (or such other
limit, if any, as may be imposed by the Code) for each calendar year in which
such Purchase Right is outstanding at any time. For purposes of the preceding
sentence, the Fair Market Value of shares purchased during a given Offering
Period shall be determined as of the Offering Date for such Offering Period. The
limitation described in this Section shall be applied in conformance with
applicable regulations under Section 423(b)(8) of the Code.

     9.   Purchase Price.
          --------------

          The Purchase Price at which each share of Stock may be acquired in an
Offering Period upon the exercise of all or any portion of a Purchase Right
shall be established by the Board; provided, however, that the Purchase Price on
each Purchase Date shall not be less than eighty-five percent (85%) of the
lesser of (a) the Fair Market Value of a share of Stock on the Participant's
Entry Date of the Offering Period or (b) the Fair Market Value of a share of
Stock on the Purchase Date. Unless otherwise provided by the Board prior to the
commencement of an Offering Period, the Purchase Price on each Purchase Date
during that Offering Period shall be eighty-five percent (85%) of the lesser of
(a) the Fair Market Value of a share of Stock on the Participant's Entry Date of
the Offering Period, or (b) the Fair Market Value of a share of Stock on the
Purchase Date.

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     10.  Accumulation of Purchase Price through Payroll Deduction.
          --------------------------------------------------------

          Shares of Stock acquired pursuant to the exercise of all or any
portion of a Purchase Right may be paid for only by means of payroll deductions
from the Participant's Compensation accumulated during the Offering Period for
which such Purchase Right was granted, subject to the following:

          10.1  Amount of Payroll Deductions. Except as otherwise provided
herein, the amount to be deducted under the Plan from a Participant's
Compensation on each payday during an Offering Period shall be determined by the
Participant's Subscription Agreement. The Subscription Agreement shall set forth
the percentage of the Participant's Compensation to be deducted on each payday
during an Offering Period in whole percentages of not less than one percent (1%)
(except as a result of an election pursuant to Section 10.3 to stop payroll
deductions) or more than ten percent (10%). The Board may change the foregoing
limits on payroll deductions effective as of any Offering Date.

          10.2  Commencement of Payroll Deductions. Payroll deductions shall
commence on the first payday following the Offering Date and shall continue to
the end of the Offering Period unless sooner altered or terminated as provided
herein.

          10.3  Election to Change or Stop Payroll Deductions. During an
Offering Period, a Participant may elect to increase or decrease the rate of or
to stop deductions from his or her Compensation by delivering to the Company's
designated office an amended Subscription Agreement authorizing such change on
or before the Change Notice Date, as defined below. A Participant may elect,
after the first payday of an Offering Period, to decrease the rate of his or her
payroll deductions to zero percent (0%), and shall nevertheless remain a
Participant in the current Offering Period unless such Participant withdraws
from the Plan as provided in Section 12.1. The "Change Notice Date" shall be the
day immediately prior to the beginning of the first pay period for which such
election is to be effective, unless a different date is established by the
Company and announced to the Participants.

          10.4  Administrative Suspension of Payroll Deductions. The Company
may, in its sole discretion, suspend a Participant's payroll deductions under
the Plan as the Company deems advisable to avoid accumulating payroll deductions
in excess of the amount that could reasonably be anticipated to purchase the
maximum number of shares of Stock permitted (a) under the Participant's Purchase
Right or (b) during a calendar year under the limit set forth in Section 8.2.
Payroll deductions shall be resumed at the rate specified in the Participant's
then effective Subscription Agreement at the beginning, respectively, of (a) the
next Offering Period, provided that the individual is a Participant in such
Offering Period or (b) the next Purchase Period the Purchase Date of which falls
in the following calendar year, unless the Participant has either withdrawn from
the Plan as provided in Section 12.1 or has ceased to be an Eligible Employee.

          10.5  Participant Accounts. Individual bookkeeping accounts shall be
maintained for each Participant. All payroll deductions from a Participant's
Compensation shall be credited to such Participant's Plan account and shall be
deposited with the general funds of

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the Company. All payroll deductions received or held by the Company may be used
by the Company for any corporate purpose.

          10.6  No Interest Paid. Interest shall not be paid on sums deducted
from a Participant's Compensation pursuant to the Plan.

          10.7  Voluntary Withdrawal from Plan Account. A Participant may
withdraw all or any portion of the payroll deductions credited to his or her
Plan account and not previously applied toward the purchase of Stock by
delivering to the Company's designated office a written notice on a form
provided by the Company for such purpose. A Participant who withdraws the entire
remaining balance credited to his or her Plan account shall be deemed to have
withdrawn from the Plan in accordance with Section 12.1. Amounts withdrawn shall
be returned to the Participant as soon as practicable after the Company's
receipt of the notice of withdrawal and may not be applied to the purchase of
shares in any Offering under the Plan. The Company may from time to time
establish or change limitations on the frequency of withdrawals permitted under
this Section, establish a minimum dollar amount that must be retained in the
Participant's Plan account, or terminate the withdrawal right provided by this
Section.

     11.  Purchase of Shares.
          ------------------

          11.1  Exercise of Purchase Right. On each Purchase Date, each
Participant who has not withdrawn from the Plan and whose participation in the
Offering has not otherwise terminated before such Purchase Date shall
automatically acquire pursuant to the exercise of the Participant's Purchase
Right the number of whole shares of Stock determined by dividing (a) the total
amount of the Participant's payroll deductions accumulated in the Participant's
Plan account during the Offering Period and not previously applied toward the
purchase of Stock by (b) the Purchase Price. However, in no event shall the
number of shares purchased by the Participant during an Offering Period exceed
the number of shares subject to the Participant's Purchase Right. No shares of
Stock shall be purchased on a Purchase Date on behalf of a Participant whose
participation in the Offering or the Plan has terminated before such Purchase
Date.

          11.2  Pro Rata Allocation of Shares. If the number of shares of Stock
which might be purchased by all Participants in the Plan on a Purchase Date
exceeds the number of shares of Stock available in the Plan as provided in
Section 4.1, the Company shall make a pro rata allocation of the remaining
shares in as uniform a manner as practicable and as the Company determines to be
equitable. Any fractional share resulting from such pro rata allocation to any
Participant shall be disregarded.

          11.3  Delivery of Certificates. As soon as practicable after each
Purchase Date, the Company shall arrange the delivery to each Participant of a
certificate representing the shares acquired by the Participant on such Purchase
Date; provided that the Company may deliver such shares to a broker designated
by the Company that will hold such shares for the benefit of the Participant.
Shares to be delivered to a Participant under the Plan shall be registered in
the name of the Participant, or, if requested by the Participant, in the name of
the Participant and his or her spouse, or, if applicable, in the names of the
heirs of the Participant.

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          11.4  Return of Cash Balance. Any cash balance remaining in a
Participant's Plan account following any Purchase Date shall be refunded to the
Participant as soon as practicable after such Purchase Date. However, if the
cash balance to be returned to a Participant pursuant to the preceding sentence
is less than the amount that would have been necessary to purchase an additional
whole share of Stock on such Purchase Date, the Company may retain the cash
balance in the Participant's Plan account to be applied toward the purchase of
shares of Stock in the subsequent Purchase Period or Offering Period, as the
case may be.

          11.5  Tax Withholding. At the time a Participant's Purchase Right is
exercised, in whole or in part, or at the time a Participant disposes of some or
all of the shares of Stock he or she acquires under the Plan, the Participant
shall make adequate provision for the federal, state, local and foreign tax
withholding obligations, if any, of the Participating Company Group which arise
upon exercise of the Purchase Right or upon such disposition of shares,
respectively. The Participating Company Group may, but shall not be obligated
to, withhold from the Participant's compensation the amount necessary to meet
such withholding obligations.

          11.6  Expiration of Purchase Right. Any portion of a Participant's
Purchase Right remaining unexercised after the end of the Offering Period to
which the Purchase Right relates shall expire immediately upon the end of the
Offering Period.

          11.7  Provision of Reports and Stockholder Information to
Participants. Each Participant who has exercised all or part of his or her
Purchase Right shall receive, as soon as practicable after the Purchase Date, a
report of such Participant's Plan account setting forth the total payroll
deductions accumulated prior to such exercise, the number of shares of Stock
purchased, the Purchase Price for such shares, the date of purchase and the cash
balance, if any, remaining immediately after such purchase that is to be
refunded or retained in the Participant's Plan account pursuant to Section 11.4.
The report required by this Section may be delivered in such form and by such
means, including by electronic transmission, as the Company may determine. In
addition, each Participant shall be provided information concerning the Company
equivalent to that information provided generally to the Company's common
stockholders.

     12.  Withdrawal from Offering or Plan.
          --------------------------------

          12.1  Voluntary Withdrawal. A Participant may withdraw from the Plan
by signing and delivering to the Company's designated office a written notice of
withdrawal on a form provided by the Company for this purpose. Such withdrawal
may be elected at any time prior to the end of an Offering Period; provided,
however, that if a Participant withdraws from the Plan after a Purchase Date,
the withdrawal shall not affect shares of Stock acquired by the Participant on
such Purchase Date. A Participant who voluntarily withdraws from the Plan or an
Offering is prohibited from resuming participation in the Plan in the same
Offering from which he or she withdrew, but may participate in any subsequent
Offering by again satisfying the requirements of Sections 5 and 7.1. The Company
may impose, from time to time, a requirement that the notice of withdrawal be on
file with the Company's designated office for a reasonable period prior to the
effectiveness of the Participant's withdrawal.

                                       11
<PAGE>

          12.2  Return of Payroll Deductions. Upon a Participant's voluntary
withdrawal from the Plan pursuant to Sections 12.1, the Participant's
accumulated payroll deductions which have not been applied toward the purchase
of shares of Stock shall be refunded to the Participant as soon as practicable
after the withdrawal, without the payment of any interest, and the Participant's
interest in the Plan or the Offering, as applicable, shall terminate. Such
accumulated payroll deductions to be refunded in accordance with this Section
may not be applied to any other Offering under the Plan.

     13.  Termination of Employment or Eligibility.
          ----------------------------------------

          Upon a Participant's ceasing, prior to a Purchase Date, to be an
Employee of the Participating Company Group for any reason, including
retirement, disability or death, or upon the failure of a Participant to remain
an Eligible Employee, the Participant's participation in the Plan shall
terminate immediately. In such event, the Participant's accumulated payroll
deductions which have not been applied toward the purchase of shares shall, as
soon as practicable, be returned to the Participant or, in the case of the
Participant's death, to the Participant's beneficiary designated in accordance
with Section 20, if any, or legal representative, and all of the Participant's
rights under the Plan shall terminate. Interest shall not be paid on sums
returned pursuant to this Section 13. A Participant whose participation has been
so terminated may again become eligible to participate in the Plan by satisfying
the requirements of Sections 5 and 7.1.

     14.  Change in Control.
          -----------------

          14.1  Definitions.

                (a)   An "Ownership Change Event" shall be deemed to have
occurred if any of the following occurs with respect to the Company: (i) the
direct or indirect sale or exchange in a single or series of related
transactions by the stockholders of the Company of more than fifty percent (50%)
of the voting stock of the Company; (ii) a merger or consolidation in which the
Company is a party; (iii) the sale, exchange, or transfer of all or
substantially all of the assets of the Company; or (iv) a liquidation or
dissolution of the Company.

                (b)   A "Change in Control" shall mean an Ownership Change Event
or a series of related Ownership Change Events (collectively, the "Transaction")
wherein the stockholders of the Company immediately before the Transaction do
not retain immediately after the Transaction, in substantially the same
proportions as their ownership of shares of the Company's voting stock
immediately before the Transaction, direct or indirect beneficial ownership of
more than fifty percent (50%) of the total combined voting power of the
outstanding voting stock of the Company or the corporation or corporations to
which the assets of the Company were transferred (the "Transferee
Corporation(s)"), as the case may be. For purposes of the preceding sentence,
indirect beneficial ownership shall include, without limitation, an interest
resulting from ownership of the voting stock of one or more corporations which,
as a result of the Transaction, own the Company or the Transferee
Corporation(s), as the case may be, either directly or through one or more
subsidiary corporations. The Board shall have the right to determine whether
multiple sales or exchanges of the voting stock of the

                                       12
<PAGE>

Company or multiple Ownership Change Events are related, and its determination
shall be final, binding and conclusive.

          14.2  Effect of Change in Control on Purchase Rights. In the event of
a Change in Control, the surviving, continuing, successor, or purchasing
corporation or parent corporation thereof, as the case may be (the "Acquiring
Corporation"), may assume the Company's rights and obligations under the Plan.
If the Acquiring Corporation elects not to assume the Company's rights and
obligations under outstanding Purchase Rights, the Purchase Date of the then
current Purchase Period shall be accelerated to a date before the date of the
Change in Control specified by the Board, but the number of shares of Stock
subject to outstanding Purchase Rights shall not be adjusted. All Purchase
Rights which are neither assumed by the Acquiring Corporation in connection with
the Change in Control nor exercised as of the date of the Change in Control
shall terminate and cease to be outstanding effective as of the date of the
Change in Control.

     15.  Nontransferability of Purchase Rights.
          -------------------------------------

          Neither payroll deductions credited to a Participant's Plan account
nor a Participant's Purchase Right may be assigned, transferred, pledged or
otherwise disposed of in any manner other than as provided by the Plan or by
will or the laws of descent and distribution. (A beneficiary designation
pursuant to Section 20 shall not be treated as a disposition for this purpose.)
Any such attempted assignment, transfer, pledge or other disposition shall be
without effect, except that the Company may treat such act as an election to
withdraw from the Plan as provided in Section 12.1. A Purchase Right shall be
exercisable during the lifetime of the Participant only by the Participant.

     16.  Compliance with Securities Law.
          ------------------------------

          The issuance of shares under the Plan shall be subject to compliance
with all applicable requirements of federal, state and foreign law with respect
to such securities. A Purchase Right may not be exercised if the issuance of
shares upon such exercise would constitute a violation of any applicable
federal, state or foreign securities laws or other law or regulations or the
requirements of any securities exchange or market system upon which the Stock
may then be listed. In addition, no Purchase Right may be exercised unless (a) a
registration statement under the Securities Act of 1933, as amended, shall at
the time of exercise of the Purchase Right be in effect with respect to the
shares issuable upon exercise of the Purchase Right, or (b) in the opinion of
legal counsel to the Company, the shares issuable upon exercise of the Purchase
Right may be issued in accordance with the terms of an applicable exemption from
the registration requirements of said Act. The inability of the Company to
obtain from any regulatory body having jurisdiction the authority, if any,
deemed by the Company's legal counsel to be necessary to the lawful issuance and
sale of any shares under the Plan shall relieve the Company of any liability in
respect of the failure to issue or sell such shares as to which such requisite
authority shall not have been obtained. As a condition to the exercise of a
Purchase Right, the Company may require the Participant to satisfy any
qualifications that may be necessary or appropriate, to evidence compliance with
any applicable law or regulation,

                                       13
<PAGE>

and to make any representation or warranty with respect thereto as may be
requested by the Company.

     17.  Rights as a Stockholder and Employee.
          ------------------------------------

          A Participant shall have no rights as a stockholder by virtue of the
Participant's participation in the Plan until the date of the issuance of a
certificate for the shares purchased pursuant to the exercise of the
Participant's Purchase Right (as evidenced by the appropriate entry on the books
of the Company or of a duly authorized transfer agent of the Company). No
adjustment shall be made for dividends, distributions or other rights for which
the record date is prior to the date such certificate is issued, except as
provided in Section 4.2. Nothing herein shall confer upon a Participant any
right to continue in the employ of the Participating Company Group or interfere
in any way with any right of the Participating Company Group to terminate the
Participant's employment at any time.

     18.  Legends.
          -------

          The Company may at any time place legends or other identifying symbols
referencing any applicable federal, state or foreign securities law restrictions
or any provision convenient in the administration of the Plan on some or all of
the certificates representing shares of Stock issued under the Plan. The
Participant shall, at the request of the Company, promptly present to the
Company any and all certificates representing shares acquired pursuant to a
Purchase Right in the possession of the Participant in order to carry out the
provisions of this Section. Unless otherwise specified by the Company, legends
placed on such certificates may include but shall not be limited to the
following:

          "THE SHARES EVIDENCED BY THIS CERTIFICATE WERE ISSUED BY THE
CORPORATION TO THE REGISTERED HOLDER UPON THE PURCHASE OF SHARES UNDER AN
EMPLOYEE STOCK PURCHASE PLAN AS DEFINED IN SECTION 423 OF THE INTERNAL REVENUE
CODE OF 1986, AS AMENDED. THE TRANSFER AGENT FOR THE SHARES EVIDENCED HEREBY
SHALL NOTIFY THE CORPORATION IMMEDIATELY OF ANY TRANSFER OF THE SHARES BY THE
REGISTERED HOLDER HEREOF. THE REGISTERED HOLDER SHALL HOLD ALL SHARES PURCHASED
UNDER THE PLAN IN THE REGISTERED HOLDER'S NAME (AND NOT IN THE NAME OF ANY
NOMINEE)."

     19.  Notification of Disposition of Shares.
          -------------------------------------

          The Company may require the Participant to give the Company prompt
notice of any disposition of shares acquired by exercise of a Purchase Right.
The Company may require that until such time as a Participant disposes of shares
acquired upon exercise of a Purchase Right, the Participant shall hold all such
shares in the Participant's name (or, if elected by the Participant, in the name
of the Participant and his or her spouse but not in the name of any nominee)
until the later of two years after the date of grant of such Purchase Right or
one year after the date of exercise of such Purchase Right. The Company may
direct that the certificates

                                       14
<PAGE>

evidencing shares acquired by exercise of a Purchase Right refer to such
requirement to give prompt notice of disposition.

     20.  Designation of Beneficiary.
          --------------------------

          20.1  Designation Procedure. A Participant may file a written
designation of a beneficiary who is to receive (a) shares and cash, if any, from
the Participant's Plan account if the Participant dies subsequent to a Purchase
Date but prior to delivery to the Participant of such shares and cash or (b)
cash, if any, from the Participant's Plan account if the Participant dies prior
to the exercise of the Participant's Purchase Right. If a married Participant
designates a beneficiary other than the Participant's spouse, the effectiveness
of such designation shall be subject to the consent of the Participant's spouse.
A Participant may change his or her beneficiary designation at any time by
written notice to the Company.

          20.2  Absence of Beneficiary Designation. If a Participant dies
without an effective designation pursuant to Section 20.1 of a beneficiary who
is living at the time of the Participant's death, the Company shall deliver any
shares or cash credited to the Participant's Plan account to the Participant's
legal representative.

     21.  Notices.
          -------

          All notices or other communications by a Participant to the Company
under or in connection with the Plan shall be deemed to have been duly given
when received in the form specified by the Company at the location, or by the
person, designated by the Company for the receipt thereof.

     22.  Amendment or Termination of the Plan.
          ------------------------------------

          The Board may at any time amend or terminate the Plan, except that (a)
no such amendment or termination shall affect Purchase Rights previously granted
under the Plan unless expressly provided by the Board and (b) no such amendment
or termination may adversely affect a Purchase Right previously granted under
the Plan without the consent of the Participant, except to the extent permitted
by the Plan or as may be necessary to qualify the Plan as an employee stock
purchase plan pursuant to Section 423 of the Code or to comply with any
applicable law, regulation or rule. In addition, an amendment to the Plan must
be approved by the stockholders of the Company within twelve (12) months of the
adoption of such amendment if such amendment would authorize the sale of more
shares than are then authorized for issuance under the Plan or would change the
definition of the corporations that may be designated by the Board as
Participating Companies.

                                       15
<PAGE>

                                 PLAN HISTORY
                                 ------------

________, 2000       Board adopts Plan, effective as of the date of the initial
                     registration of Stock under Section 12 of the Exchange Act,
                     with an initial reserve of 500,000 shares. The Board also
                     established that the share reserve will be increased
                     cumulatively on each January 1 from January 1, 2001 through
                     January 1, 2010 by the lesser of (i) 2% of the shares of
                     common stock issued and outstanding on the immediately
                     preceding December 31, (ii) __________ shares, or (iii)
                     such lesser number of shares determined by the Board.

___________, 2000    Stockholders approve the Plan.
<PAGE>

                                VALICERT, INC.
                       2000 EMPLOYEE STOCK PURCHASE PLAN
                            SUBSCRIPTION AGREEMENT


NAME (Please print):____________________________________________________________
                    (Last)                    (First)              (Middle)

[_]  Original application for the Offering Period beginning (date):_____________

[_]  Change in payroll deduction rate effective with the pay period ending
     (date):______________

[_]  Change of beneficiary.

I.   SUBSCRIPTION

     I elect to participate in the 2000 Employee Stock Purchase Plan (the
"Plan") of ValiCert, Inc. (the "Company") and to subscribe to purchase shares of
the Company's Common Stock in accordance with this Subscription Agreement and
the Plan.

     I authorize payroll deductions of __________ percent (in whole percentages
not less than 1%, unless an election to stop deductions is being made, or more
than 10%) of my "Compensation" on each payday throughout the "Offering Period"
in accordance with the Plan. I understand that these payroll deductions will be
accumulated for the purchase of shares of Common Stock at the applicable
purchase price determined in accordance with the Plan. Except as otherwise
provided by the Plan, I will automatically purchase shares on each "Purchase
Date" unless I withdraw from the Offering or the Plan by giving written notice
on a form provided by the Company or unless my eligibility or employment
terminates.

     I understand that I will automatically participate in each subsequent
Offering that commences immediately after the last day of an Offering in which I
am participating until I withdraw from the Plan by giving written notice on a
form provided by the Company or my eligibility or employment terminates.

     Shares I purchase under the Plan should be issued in the name(s) set forth
below. (Shares may be issued in the participant's name alone or together with
the participant's spouse as community property or in joint tenancy.)

     NAME(S) (please print): ___________________________________________________

     ADDRESS: __________________________________________________________________

     MY SOCIAL SECURITY NUMBER: ________________________________________________

     I agree to make adequate provision for the federal, state, local and
foreign tax withholding obligations, if any, which arise upon my purchase of
shares under the Plan and/or my disposition of shares. The Company may withhold
from my compensation the amount necessary to meet such withholding obligations.

     I agree that, unless otherwise permitted by the Company, until I dispose of
shares I purchase under the Plan, I will hold such shares in the name(s) entered
above (and not in the name of any nominee) until the later of (i) two years
after the first day of the Offering Period in which I purchased the shares and
(ii) one year after the Purchase Date on which I purchased the shares. This
restriction only applies to the name(s) in which shares are held and does not
                                                                          ---
affect my ability to dispose of Plan shares.

     I agree that I will notify the Chief Financial Officer of the Company in
writing within 30 days after any sale, gift, transfer or other disposition of
any kind prior to the end of the periods
<PAGE>

referred to in the preceding paragraph (a "Disqualifying Disposition") of any
shares I purchased under the Plan. If I do not respond within 30 days of the
date of a Disqualifying Disposition Survey delivered to me by certified mail,
the Company is authorized to treat my nonresponse as my notice to the Company of
a Disqualifying Disposition and to compute and report to the Internal Revenue
Service the ordinary income I must recognize upon such Disqualifying
Disposition.

II.     BENEFICIARY DESIGNATION

        In the event of my death, I designate the following as my beneficiary to
receive all payments and shares then due me under the Plan:

        BENEFICIARY'S NAME (please print):______________________________________
                                          (First)       (Middle)        (Last)

        RELATIONSHIP:___________________      SOC. SEC. NO.:____________________

        ADDRESS:________________________________________________________________


        If you are married and your beneficiary is someone other than your
spouse, then your spouse must sign and date this form as indicated below. If you
are not married when you designate a beneficiary and you later become married,
or if you later become married to a different person, the beneficiary
designation previously made will be automatically revoked. Payments and shares
then due you upon your death will be delivered to your legal representative
unless you have completed a new beneficiary designation and it is consented to
by your then spouse.

III.    CONSENT OF SPOUSE

        I am the spouse of______________________________________.  I consent to
the above designation of a beneficiary other than me of payments and shares due
my spouse under the Plan.



Date:_____________________________      ________________________________________
                                        Signature of Participant's Spouse

IV.     PARTICIPANT DECLARATION

        Any election I have made on this form revokes all prior elections with
regard to this form.

        I am familiar with the provisions of the Plan and agree to participate
in the Plan subject to all of its provisions. I understand that the Board of
Directors of the Company reserves the right to terminate the Plan or to amend
the Plan and my right to purchase stock under the Plan to the extent provided by
the Plan. I understand that the effectiveness of this Subscription Agreement is
dependent upon my eligibility to participate in the Plan and is subject to the
provisions of the Plan.



Date:_____________________________      ________________________________________
                                        Signature of Participant
<PAGE>

                                VALICERT, INC.
                       2000 EMPLOYEE STOCK PURCHASE PLAN
                             NOTICE OF WITHDRAWAL


NAME (Please print):____________________________________________________________
                    (Last)               (First)             (Middle)

[_]  Withdrawal from Plan in full.

[_]  Partial withdrawal of payroll deductions from Plan account.

I.   WITHDRAWAL IN FULL

     I elect to withdraw from the ValiCert, Inc. 2000 Employee Stock Purchase
Plan (the "Plan") and the Offering which began on (date) ____________________
and in which I am participating (the "Current Offering").

     Elect either A or B below:

[_]  A.   Immediate Termination. I elect to terminate immediately my
          participation in the Current Offering and the Plan. I request that the
          Company cease all further payroll deductions under the Plan (provided
          I have given sufficient notice before the next payday). My payroll
          deductions not previously used to purchase shares should not be used
                                                                   ---
          to purchase shares in the Current Offering. Instead, I request that
          all such amounts be paid to me as soon as practicable. I understand
          that this election immediately terminates my interest in the Current
          Offering and in the Plan.

[_]  B.   Termination After Next Purchase. I elect to terminate my participation
          in the Plan following my purchase of shares on the next Purchase Date
          of the Current Offering. I request that the Company cease all further
          payroll deductions under the Plan (provided I have given sufficient
          notice before the next payday). All payroll deductions credited to my
          Plan account should be used to purchase shares on the next Purchase
          Date of the Current Offering to the extent permitted by the Plan. I
          understand that this election will terminate my interest in the Plan
          immediately following such purchase. I request that any cash balance
          remaining in my Plan account after my purchase of shares be paid to me
          as soon as practicable.

     I understand that I am terminating my interest in the Plan and that no
further payroll deductions will be made (provided I have given sufficient notice
before the next payday), unless I elect to become a participant in another
Offering by filing a new Subscription Agreement with the Company. I understand
that I will receive no interest on the amounts paid to me from my Plan account,
and that I may not apply such amounts to any other Offering under the Plan or
any other employee stock purchase plan of the Company.

II.  PARTIAL WITHDRAWAL OF PAYROLL DEDUCTIONS

     Amount of withdrawal requested: $ ___________________

     I request that the above amount not previously used to purchase shares
under the Plan be withdrawn from my Plan account and paid to me as soon as
practicable. If the amount requested constitutes the entire balance of my Plan
account, I understand that I will be treated as having elected to withdraw in
full from the Plan in accordance with alternative A above. I understand that I
will receive no interest on the amounts paid to me from my Plan account and that
I may not apply such amounts to any other Offering under the Plan or any other
employee stock purchase plan of the Company.



Date: ______________________________  Signature: _______________________________