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                                                                  EXHIBIT 10.57

                          CADENCE DESIGN SYSTEMS, INC.
                        2001 EMPLOYEE STOCK PURCHASE PLAN

                   ADOPTED BY BOARD OF DIRECTORS JULY 13, 2001
                             TERMINATION DATE: NONE

                STATUS AS SECTION 423 PLAN DEPENDS ON SHAREHOLDER
                         APPROVAL AT 2002 ANNUAL MEETING

1.      PURPOSE.

        (a) The Plan was established effective as of July 13, 2001.

        (b) The purpose of the Plan is to provide a means by which Employees of
the Company and certain designated Affiliates may be given an opportunity to
purchase Shares of the Company.

        (c) The Company, by means of the Plan, seeks to secure and retain the
services of new Employees for itself and/or its designated Affiliates and to
provide incentives for such persons to exert maximum efforts for the success of
the Company and/or such Affiliates.

        (d) The Company intends that the Rights to purchase Shares granted under
the Plan be considered options issued under an "employee stock purchase plan,"
as that term is defined in Section 423(b) of the Code, and will seek shareholder
approval of the Plan, in accordance with Section 423(b)(2) of the Code.

2.      DEFINITIONS.

        (a) "AFFILIATE" means any parent corporation or subsidiary corporation,
whether now or hereafter existing, as those terms are defined in Sections 424(e)
and (f), respectively, of the Code.

        (b) "BOARD" means the Board of Directors of the Company.

        (c) "CODE" means the United States Internal Revenue Code of 1986, as
amended.

        (d) "COMMITTEE" means a committee of the Board appointed by the Board in
accordance with subsection 3(c) of the Plan.

        (e) "COMPANY" means Cadence Design Systems, Inc., a Delaware
corporation.

        (f) "DIRECTOR" means a member of the Board.

        (g) "ELIGIBLE EMPLOYEE" means an Employee who meets the requirements set
forth in the Offering Memorandum for eligibility to participate in the Offering.

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        (h) "EMPLOYEE" means any person, including Officers and Directors,
employed by the Company or an Affiliate of the Company designated for
participation in the Plan. Neither service as a Director nor payment of a
director's fee shall be sufficient to constitute "employment" by the Company or
the Affiliate.

        (i) "EMPLOYEE STOCK PURCHASE PLAN" means a plan that grants rights
intended to be options issued under an "employee stock purchase plan," as that
term is defined in Section 423(b) of the Code.

        (j) "EXCHANGE ACT" means the United States Securities Exchange Act of
1934, as amended.

        (k) "FAIR MARKET VALUE" means the value of a security, as determined in
good faith by the Board. If the security is listed on the New York Stock
Exchange or any other established stock exchange or traded on the Nasdaq
National Market or the Nasdaq SmallCap Market, then, except as otherwise
provided in the Offering Memorandum, the Fair Market Value of the security shall
be the closing sales price (rounded up where necessary to the nearest whole
cent) for such security (or the closing bid, if no sales were reported) as
quoted on such exchange or market (or, in the event that the security is traded
on more than one such exchange or market, the exchange or market with the
greatest volume of trading in the relevant security of the Company) on the
trading day occurring on or closest to the relevant determination date, as
reported in The Wall Street Journal or such other source as the Board deems
reliable, and on the date as determined more precisely in the Offering
Memorandum.

        (l) "NON-EMPLOYEE DIRECTOR" means a Director who either (i) is not a
current Employee or Officer of the Company or its parent or subsidiary, does not
receive compensation (directly or indirectly) from the Company or its parent or
subsidiary for services rendered as a consultant or in any capacity other than
as a Director (except for an amount as to which disclosure would not be required
under Item 404(a) of Regulation S-K promulgated pursuant to the Securities Act
("Regulation S-K")), does not possess an interest in any other transaction as to
which disclosure would be required under Item 404(a) of Regulation S-K, and is
not engaged in a business relationship as to which disclosure would be required
under Item 404(b) of Regulation S-K; or (ii) is otherwise considered a
"non-employee director" for purposes of Rule 16b-3.

        (m) "OFFERING" means the grant of Rights to purchase Shares under the
Plan to Eligible Employees.

        (n) "OFFERING DATE" means a date selected by the Board for an Offering
to commence.

        (o) "OFFERING MEMORANDUM" means a memorandum describing the terms of the
then current or otherwise relevant Offering.

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        (p) "PARTICIPANT" means an Eligible Employee who holds an outstanding
Right granted pursuant to the Plan or, if applicable, such other person who
holds an outstanding Right granted under the Plan.

        (q) "PLAN" means this 2001 Employee Stock Purchase Plan.

        (r) "PURCHASE DATE" means one or more dates established by the Board
during an Offering on which Rights granted under the Plan shall be exercised and
purchases of Shares carried out in accordance with such Offering.

        (s) "RIGHT" means an option to purchase Shares granted pursuant to the
Plan.

        (t) "RULE 16b-3" means Rule 16b-3 of the Exchange Act or any successor
to Rule 16b-3 as in effect with respect to the Company at the time discretion is
being exercised regarding the Plan.

        (u) "SECURITIES ACT" means the United States Securities Act of 1933, as
amended.

        (v) "SHARE" means a share of the common stock of the Company.

3.      ADMINISTRATION.

        (a) The Board shall administer the Plan unless and until the Board
delegates administration to a Committee, as provided in subsection 3(c). Whether
or not the Board has delegated administration, the Board shall have the final
power to determine all questions of policy and expediency that may arise in the
administration of the Plan.

        (b) The Board (or the Committee) shall have the power, subject to, and
within the limitations of, the express provisions of the Plan:

               (i) To determine when and how Rights to purchase Shares shall be
granted and the provisions of each Offering of such Rights (which need not be
identical).

               (ii) To designate from time to time which Affiliates of the
Company shall be eligible to participate in the Plan.

               (iii) To construe and interpret the Plan and Rights granted under
it, and to establish, amend and revoke rules and regulations for its
administration. The Board, in the exercise of this power, may correct any
defect, omission or inconsistency in the Plan, in a manner and to the extent it
shall deem necessary or expedient to make the Plan fully effective.

               (iv) To amend the Plan as provided in Section 14.

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               (v) Generally, to exercise such powers and to perform such acts
as it deems necessary or expedient to promote the best interests of the Company
and its Affiliates and to carry out the intent that the Plan be treated as an
Employee Stock Purchase Plan.

        (c) The Board may delegate administration of the Plan to a Committee of
the Board composed of two (2) or more members, all of the members of which
Committee may be, in the discretion of the Board, Non-Employee Directors. If
administration is delegated to a Committee, the Committee shall have, in
connection with the administration of the Plan, the powers theretofore possessed
by the Board, including the power to delegate to a subcommittee of two (2) or
more Non-Employee Directors any of the administrative powers the Committee is
authorized to exercise (and references in this Plan to the Board shall
thereafter be to the Committee or such a subcommittee), subject, however, to
such resolutions, not inconsistent with the provisions of the Plan, as may be
adopted from time to time by the Board. The Board may abolish the Committee at
any time and revest in the Board the administration of the Plan.

4.      SHARES SUBJECT TO THE PLAN.

        (a) Subject to the provisions of Section 13 relating to adjustments upon
changes in securities, the Shares that may be sold pursuant to Rights granted
under the Plan shall not exceed in the aggregate One Million Seven Hundred Fifty
Thousand (1,750,000) Shares. If any Right granted under the Plan shall for any
reason terminate without having been exercised, the Shares not purchased under
such Right shall again become available for the Plan.

        (b) The Shares subject to the Plan may be unissued Shares or Shares that
have been bought on the open market at prevailing market prices or otherwise.

5.      GRANT OF RIGHTS; OFFERING.

        (a) The Board may from time to time grant or provide for the grant of
Rights to purchase Shares under the Plan to Eligible Employees in an Offering on
one or more Offering Dates selected by the Board. All Employees granted Rights
under the Plan shall have the same rights and privileges, except that such
rights may differ only to the extent permitted under Section 423 of the Code.
Each Offering shall be in such form and shall contain such terms and conditions
as the Board shall deem appropriate, which shall comply with the requirements of
Section 423(b)(5) of the Code that all Employees granted Rights to purchase
Shares under the Plan shall have the same rights and privileges. The terms and
conditions of an Offering shall be incorporated by reference into the Plan and
treated as part of the Plan. The provisions of separate Offerings need not be
identical, but each Offering shall include (through incorporation of the
provisions of this Plan by reference in the Offering Memorandum or otherwise)
the period during which the Offering shall be effective, which period shall not
exceed twenty-seven (27) months beginning with the Offering Date, and the
substance of the provisions contained in Sections 6 through 9, inclusive.

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        (b) If a Participant has more than one Right outstanding under the Plan,
unless he or she otherwise indicates in agreements or notices delivered
hereunder: (i) each agreement or notice delivered by that Participant will be
deemed to apply to all of his or her Rights under the Plan, and (ii) an
earlier-granted Right (or a Right with a lower exercise price, if two Rights
have identical grant dates) will be exercised to the fullest possible extent
before a later-granted Right (or a Right with a higher exercise price if two
Rights have identical grant dates) will be exercised.

6.      ELIGIBILITY.

        (a) Rights may be granted only to Employees of the Company or to
Employees of an Affiliate, as the Board may designate as provided in subsection
3(b). Except as provided in subsection 6(b), an Employee shall not be eligible
to be granted Rights under the Plan unless, on the Offering Date, such Employee
has been in the employ of the Company or the Affiliate, as the case may be, for
such continuous period preceding such grant as the Board may require, but in no
event shall the required period of continuous employment be equal to or greater
than two (2) years. Rights shall be granted to all Eligible Employees of any
corporation whose Employees are granted any Rights under this Plan by reason of
their employment by such corporation, except that there may be excluded
Employees (i) whose customary employment is fewer than 20 hours per week (or
such lower amount as established in the Offering Memorandum), (ii) whose
customary employment is for not more than five months during any calendar year
(or such shorter period as established in the Offering Memorandum), (iii) who
have completed less than two years of employment by the Company or Affiliate (or
such shorter period as established in the Offering Memorandum), (iv) who are
"highly compensated" within the meaning of Section 414(q) or the Code, and (v)
who otherwise may be excluded without violating Section 423 of the Code or other
applicable law.

        (b) The Board may provide that each person who, during the course of an
Offering, first becomes an Eligible Employee will, on a date or dates specified
in the Offering Memorandum which coincides with the day on which such person
becomes an Eligible Employee or which occurs thereafter, receive a Right under
that Offering, which Right shall thereafter be deemed to be a part of that
Offering. Such Right shall have the same characteristics as any Rights
originally granted under that Offering, as described herein, except that:

               (i) the date on which such Right is granted shall be the
"Offering Date" of such Right for all purposes, including determination of the
exercise price of such Right;

               (ii) the period of the Offering with respect to such Right shall
begin on its Offering Date and end coincident with the end of such Offering; and

               (iii) the Board may provide that if such person first becomes an
Eligible Employee within a specified period of time before the end of the
Offering, he or she will not receive any Right under that Offering.

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        (c) No Employee shall be eligible for the grant of any Rights under the
Plan if, immediately after any such Rights are granted, such Employee owns stock
possessing five percent (5%) or more of the total combined voting power or value
of all classes of stock of the Company or of any Affiliate. For purposes of this
subsection 6(c), the rules of Section 424(d) of the Code shall apply in
determining the stock ownership of any Employee, and stock which such Employee
may purchase under all outstanding rights and options shall be treated as stock
owned by such Employee.

        (d) An Eligible Employee may be granted Rights under the Plan only if
such Rights, together with any other Rights granted under all Employee Stock
Purchase Plans of the Company and any Affiliates, as specified by Section
423(b)(8) of the Code, do not permit such Eligible Employee's rights to purchase
Shares or shares of any Affiliate to accrue at a rate which exceeds twenty five
thousand dollars ($25,000) of the fair market value of such Shares (determined
at the time such Rights are granted) for each calendar year in which such Rights
are outstanding at any time. The provisions of Section 423(b)(8) of the Code
shall govern the application of this Section 6(d).

7.      RIGHTS; PURCHASE PRICE.

        (a) On each Offering Date, each Eligible Employee, pursuant to an
Offering made under the Plan, shall be granted the Right to purchase up to the
number of Shares purchasable either:

               (i) with a minimum and maximum percentage or percentages
designated by the Board (which need not be uniform throughout the Offering, but
any fluctuations in such percentages shall be applied equally to all Employees
participating in the Offering) not exceeding twenty percent (20%) of such
Employee's Earnings (as defined by the Board in each Offering Memorandum) during
the period which begins on the Offering Date (or such later date as the Board
determines for a particular Offering) and ends on the date stated in the
Offering, which date shall be no later than the end of the Offering, which
amount shall, as specified in the Offering Memorandum for that Offering, be (1)
withheld, in whole or in part, from such Employee's Earnings during the period
which begins on the Offering Date (or such later date as the Board determines
for a particular Offering) and ends on the date stated in the Offering
Memorandum for that Offering, which date shall be no later than the end of the
Offering and/or (2) contributed, in whole or in part, by such Employee during
such period; or

               (ii) with a maximum dollar amount designated by the Board that,
as the Board determines for a particular Offering, (1) shall be withheld, in
whole or in part, from such Employee's Earnings (as defined by the Board in each
Offering Memorandum) during the period which begins on the Offering Date (or
such later date as the Board determines for a particular Offering) and ends on
the date stated in the Offering, which date shall be no later than the end of
the Offering and/or (2) shall be contributed, in whole or in part, by such
Employee during such period.

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        (b) The Board shall establish one or more Purchase Dates during an
Offering on which Rights granted under the Plan shall be exercised and purchases
of Shares carried out in accordance with such Offering.

        (c) In connection with each Offering made under the Plan, the Board may
specify a maximum amount of Shares that may be purchased by any Participant as
well as a maximum aggregate amount of Shares that may be purchased by all
Participants pursuant to such Offering. In addition, in connection with each
Offering that contains more than one Purchase Date, the Board may specify a
maximum aggregate amount of Shares which may be purchased by all Participants on
any given Purchase Date under the Offering. If the aggregate purchase of Shares
upon exercise of Rights granted under the Offering would exceed any such maximum
aggregate amount, the Board shall make a pro rata allocation of the Shares
available in as nearly a uniform manner as shall be practicable and as it shall
deem to be equitable and consistent with the requirements of Section 423 of the
Code.

        (d) The purchase price of Shares acquired pursuant to Rights granted
under the Plan shall be not less than the lesser of:

               (i) an amount equal to eighty-five percent (85%) of the fair
market value of the Shares on the Offering Date; or

               (ii) an amount equal to eighty-five percent (85%) of the fair
market value of the Shares on the Purchase Date.

8.      PARTICIPATION; WITHDRAWAL; TERMINATION.

        (a) An Eligible Employee may become a Participant in the Plan pursuant
to an Offering by delivering an enrollment form to the Company within the time
specified in the Offering Memorandum, in such form as the Company provides. Each
such agreement shall authorize payroll deductions of up to the maximum
percentage specified by the Board of such Employee's Earnings during the
Offering (as defined in each Offering). The payroll deductions made for each
Participant shall be credited to a bookkeeping account for such Participant
under the Plan and either may be deposited with the general funds of the Company
or may be deposited in a separate account in the name of, and for the benefit
of, such Participant with a financial institution designated by the Company. To
the extent provided in the Offering, a Participant may reduce (including to
zero) or increase such payroll deductions. To the extent provided in the
Offering, a Participant may begin such payroll deductions after the beginning of
the Offering. A Participant may make additional payments into his or her account
only if specifically provided for in the Offering Memorandum and only if the
Participant has not already had the maximum permitted amount withheld during the
Offering.

        (b) At any time during an Offering, a Participant may terminate his or
her payroll deductions under the Plan and withdraw from the Offering by
delivering to the Company a notice of withdrawal in such form as the Company
provides. Such withdrawal may be elected at any

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time prior to the end of the Offering except as provided by the Board in the
Offering Memorandum. Upon such withdrawal from the Offering by a Participant,
the Company shall distribute to such Participant all of his or her accumulated
payroll deductions (reduced to the extent, if any, such deductions have been
used to acquire Shares for the Participant) under the Offering, without interest
unless otherwise specified in the Offering Memorandum, and such Participant's
interest in that Offering shall be automatically terminated. A Participant's
withdrawal from an Offering will have no effect upon such Participant's
eligibility to participate in any other Offerings under the Plan but such
Participant will be required to deliver a new participation agreement in order
to participate in subsequent Offerings under the Plan.

        (c) Rights granted pursuant to any Offering under the Plan shall
terminate immediately upon cessation of any participating Employee's employment
with the Company and its designated Affiliates for any reason (subject to any
post-employment participation period required by law) or other lack of
eligibility. The Company shall distribute to such terminated Employee all of his
or her accumulated payroll deductions (reduced to the extent, if any, such
deductions have been used to acquire Shares for the terminated Employee) under
the Offering, without interest unless otherwise specified in the Offering
Memorandum. If the accumulated payroll deductions have been deposited with the
Company's general funds, then the distribution shall be made from the general
funds of the Company, without interest. If the accumulated payroll deductions
have been deposited in a separate account with a financial institution as
provided in subsection 8(a), then the distribution shall be made from the
separate account, without interest unless otherwise specified in the Offering
Memorandum.

        (d) Rights granted under the Plan shall not be transferable by a
Participant otherwise than by will or the laws of descent and distribution, or
by a beneficiary designation as provided in Section 15 and, otherwise during his
or her lifetime, shall be exercisable only by the person to whom such Rights are
granted.

9.      EXERCISE.

        (a) On each Purchase Date specified in the relevant Offering Memorandum,
each Participant's accumulated payroll deductions and other additional payments
specifically provided for in the Offering (without any increase for interest)
will be applied to the purchase of Shares up to the maximum amount of Shares
permitted pursuant to the terms of the Plan and the applicable Offering, at the
purchase price specified in the Offering Memorandum for that Offering. No
fractional Shares shall be issued upon the exercise of Rights granted under the
Plan unless specifically provided for in the Offering and permitted by law.

        (b) Unless otherwise specifically provided in the Offering Memorandum,
the amount, if any, of accumulated payroll deductions remaining in any
Participant's account after the purchase of Shares that is equal to the amount
required to purchase one or more whole Shares on the final Purchase Date of the
Offering shall be distributed in full to the Participant at the end of the
Offering, without interest. If the accumulated payroll deductions have been
deposited with the Company's general funds, then the distribution shall be made
from the general funds of the

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Company, without interest. If the accumulated payroll deductions have been
deposited in a separate account with a financial institution as provided in
subsection 8(a), then the distribution shall be made from the separate account,
without interest unless otherwise specified in the Offering Memorandum.

        (c) The amount, if any, of accumulated payroll deductions remaining in
any Participant's account after the purchase of Shares that is less than the
amount required to purchase one whole Share on the final Purchase Date of the
Offering shall be carried forward, without interest, into the next Offering.

        (d) No Rights granted under the Plan may be exercised to any extent
unless the Shares to be issued upon such exercise under the Plan (including
Rights granted thereunder) are covered by an effective registration statement
pursuant to the Securities Act and the Plan is in material compliance with all
applicable state, foreign and other securities and other laws applicable to the
Plan. If on a Purchase Date in any Offering hereunder the Shares are not so
registered or the Plan is not in such compliance, no Rights granted under the
Plan or any Offering shall be exercised on such Purchase Date, and the Purchase
Date shall be delayed until the Shares are subject to such an effective
registration statement and the Plan is in such compliance, except that the
Purchase Date shall not be delayed more than twelve (12) months and the Purchase
Date shall in no event be more than twenty-seven (27) months from the Offering
Date. If, on the Purchase Date of any Offering hereunder, as delayed to the
maximum extent permissible, the Shares are not registered and the Plan is not in
such compliance, no Rights granted under the Plan or any Offering shall be
exercised and all amounts contributed by the Participant during the Offering
(reduced to the extent, if any, such deductions have been used to acquire
Shares) shall be distributed to the Participants, without interest unless
otherwise specified in the Offering Memorandum. If the amounts contributed by
the Participant have been deposited with the Company's general funds, then the
distribution shall be made from the general funds of the Company, without
interest. If the amounts contributed by the Participant have been deposited in a
separate account with a financial institution as provided in subsection 8(a),
then the distribution shall be made from the separate account, without interest
unless otherwise specified in the Offering Memorandum.

10.     COVENANTS OF THE COMPANY.

        (a) During the terms of the Rights granted under the Plan, the Company
shall ensure that the amount of Shares required to satisfy such Rights are
available.

        (b) The Company shall seek to obtain from each federal, state, foreign
or other regulatory commission or agency having jurisdiction over the Plan such
authority as may be required to issue and sell Shares upon exercise of the
Rights granted under the Plan. If, after reasonable efforts, the Company is
unable to obtain from any such regulatory commission or agency the authority
which counsel for the Company deems necessary for the lawful issuance and sale
of Shares under the Plan, the Company shall be relieved from any liability for
failure to issue and sell Shares upon exercise of such Rights unless and until
such authority is obtained.

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11.     USE OF PROCEEDS FROM SHARES.

        Proceeds from the sale of Shares pursuant to Rights granted under the
Plan shall constitute general funds of the Company.

12.     RIGHTS AS A STOCKHOLDER AND EMPLOYEE.

        (a) A Participant shall not be deemed to be the holder of, or to have
any of the rights of a holder with respect to, Shares subject to Rights granted
under the Plan unless and until the Participant's Shares acquired upon exercise
of Rights under the Plan are recorded in the books of the Company.

        (b) Neither the Plan nor the grant of any Right thereunder shall confer
any right on any Employee to remain in the employ of the Company or any
Affiliate or restrict the right of the Company or any Affiliate to terminate
such Employee's employment.

13.     ADJUSTMENTS UPON CHANGES IN SECURITIES.

        (a) Subject to any required action by the stockholders of the Company,
the number of Shares covered by each Right under the Plan that has not yet been
exercised and the number of Shares that have been authorized for issuance under
the Plan but have not yet been placed under a Right (collectively, the
"Reserves"), as well as the price per Share covered by each Right under the Plan
that has not yet been exercised, shall be proportionately adjusted for any
increase or decrease in the number of issued Shares resulting from a stock split
or the payment of stock dividend (but only on the Common Stock) or any other
increase or decrease in the number of Shares effected without receipt of
consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected
without receipt of consideration." Such adjustment shall be made by the Board,
whose determination in that respect shall be final, binding and conclusive.
Except as expressly provided herein, no issue by the Company of shares of stock
of any class, or securities convertible into shares of stock of any class, shall
affect, and no adjustment by reason thereof shall be made with respect to, the
number or price of Shares subject to a Right.

        (b) In the event of the proposed dissolution or liquidation of the
Company, any and all Offerings shall terminate immediately prior to the
consummation of such proposed action, unless otherwise provided by the Board.
The Board may, in the exercise of its sole discretion in such instances, declare
that the Rights under the Plan shall terminate as of a date fixed by the Board
and give each Participant the right to exercise his or her Right. In the event
of a proposed sale of all or substantially all of the assets of the Company, or
the merger or consolidation of the Company with or into another corporation or a
parent or subsidiary of such successor corporation when the Company is not the
surviving corporation, or a reverse merger in which the Company is the surviving
corporation but the Shares outstanding immediately preceding the merger are
converted by virtue of the merger into other property, whether in the form of
securities, cash or otherwise, any and all Offerings shall terminate immediately
prior to the consummation of such

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proposed action, unless otherwise provided by the Board. The Board may, in the
exercise of its sole discretion in such instances, and in lieu of assumption or
substitution of the Rights, provide that each Participant shall have the right
to exercise his or her Right. If the Board makes a Right exercisable in lieu of
assumption or substitution in the event of a merger or sale of assets, the Board
shall notify the Participant that the Right shall be fully exercisable for a
period of twenty (20) days from the date of such notice (or such other period of
time as the Board shall determine), and the Right shall terminate upon the
expiration of such period.

        (c) The Board may, if it so determines in the exercise of its sole
discretion, also make provision for adjusting the Reserves, as well as the price
per Share covered by each outstanding Right, in the event that the Company
effects one or more reorganizations, recapitalizations, rights offering, or
other increases or reductions of outstanding Shares, and in the event of the
Company being consolidated with or merged into any other corporation.

14.     AMENDMENT OF THE PLAN.

        (a) The Board at any time, and from time to time, may amend the Plan.
However, except as provided in Section 13 relating to adjustments upon changes
in securities and except as to minor amendments to benefit the administration of
the Plan, to take account of a change in legislation or to obtain or maintain
favorable tax, exchange control or regulatory treatment for Participants or the
Company or any Affiliate, no amendment shall be effective unless approved by the
stockholders of the Company to the extent stockholder approval is necessary for
the Plan to satisfy the requirements of Section 423 of the Code, Rule 16b-3
under the Exchange Act or any Nasdaq or other securities exchange listing
requirements. Currently under the Code, stockholder approval within twelve (12)
months before or after the adoption of the amendment is required where the
amendment will:

               (i) Increase the amount of Shares that may be issued under the
Plan;

               (ii) Modify the provisions as to eligibility for participation in
the Plan to the extent such modification requires stockholder approval in order
for the Plan to obtain employee stock purchase plan treatment under Section 423
of the Code; or

               (iii) Modify the Plan in any other way if such modification
requires stockholder approval in order for the Plan to obtain employee stock
purchase plan treatment under Section 423 of the Code.

        (b) It is expressly contemplated that the Board may amend the Plan in
any respect the Board deems necessary or advisable to provide Employees with the
maximum benefits provided or to be provided under the provisions of the Code and
the regulations promulgated thereunder relating to Employee Stock Purchase Plans
and/or to bring the Plan and/or Rights granted under it into compliance
therewith.

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        (c) Rights and obligations under any Rights granted before amendment of
the Plan shall not be impaired by any amendment of the Plan without the consent
of the person to whom such Rights were granted, or except as necessary to comply
with any laws or governmental regulations, or except as necessary to ensure that
the Plan and/or Rights granted under the Plan comply with the requirements of
Section 423 of the Code.

15.     DESIGNATION OF BENEFICIARY.

        (a) A Participant may file a written designation of a beneficiary who is
to receive any Shares and/or cash, if any, from the Participant's account under
the Plan in the event of such Participant's death subsequent to the end of an
Offering but prior to delivery to the Participant 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 during an Offering.

        (b) The Participant may change such designation of beneficiary at any
time by written notice. In the event of the death of a Participant and in the
absence of a beneficiary validly designated under the Plan 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 sole 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.

16.     TERMINATION OR SUSPENSION OF THE PLAN.

        (a) The Board in its discretion may suspend or terminate the Plan at any
time. Unless sooner terminated, the Plan shall terminate at the time that all of
the Shares available for issuance under the Plan, as increased and/or adjusted
from time to time, have been issued under the terms of the Plan. No Rights may
be granted under the Plan while the Plan is suspended or after it is terminated.

        (b) Rights and obligations under any Rights granted while the Plan is in
effect shall not be impaired by suspension or termination of the Plan, except as
expressly provided in the Plan (including any Offering Memorandum) or with the
consent of the person to whom such Rights were granted, or except as necessary
to comply with any laws or governmental regulation, or except as necessary to
ensure that the Plan and/or Rights granted under the Plan comply with the
requirements of Section 423 of the Code.

17.     TAX WITHHOLDING AND OTHER TAXES AND CONTRIBUTIONS

        The Company and any Affiliate whose Employees are Eligible Employees
shall withhold from each Participant's earnings or other amounts payable to the
Participant income tax, social

                                       12

<PAGE>   13

security taxes and other taxes required or, if the Company or such Affiliate so
chose, permitted, to be withheld with respect to such amounts under applicable
law. The Participant shall be liable for all such amounts. In the event the
Company or an Affiliate does not withhold such taxes or a Participant's earnings
are insufficient to satisfy such withholding, the Company or an Affiliate shall
have the right to effect the sale of such Participant's Shares on behalf of the
Participant and pay the proceeds to the Company or to the Affiliate, retain
amounts that have been deducted from payroll and would otherwise be used to
purchase Shares, withhold such taxes from amounts otherwise due to the
Participant, or take any other action that they deem necessary to cause the
Participant to fulfill such obligation.

18.     EFFECTIVE DATE OF PLAN.

        The Plan shall become effective upon adoption by the Board.

                                       13<PAGE>   1
                                                                  EXHIBIT 10.58

                          CADENCE DESIGN SYSTEMS, INC.
                   NON-QUALIFIED EMPLOYEE STOCK PURCHASE PLAN

                   ADOPTED BY BOARD OF DIRECTORS JULY 13, 2001
                        STOCKHOLDER APPROVAL NOT REQUIRED
                             TERMINATION DATE: NONE

1.      PURPOSE.

        (a) The purpose of the Plan is to provide a means by which Employees of
the Company and certain designated Affiliates may be given an opportunity to
purchase Shares of the Company.

        (b) The Company, by means of the Plan, seeks to secure and retain the
services of new Employees for itself and/or its designated Affiliates and to
provide incentives for such persons to exert maximum efforts for the success of
the Company and/or such Affiliates.

2.      DEFINITIONS.

        (a) "AFFILIATE" means any entity approved by the Board in which the
Company holds a direct or indirect ownership interest (by value or voting
rights) of at least 50%.

        (b) "BOARD" means the Board of Directors of the Company.

        (c) "COMMITTEE" means a committee of the Board appointed by the Board in
accordance with subsection 3(c) of the Plan.

        (d) "COMPANY" means Cadence Design Systems, Inc., a Delaware
corporation.

        (e) "DIRECTOR" means a member of the Board.

        (f) "ELIGIBLE EMPLOYEE" means an Employee who meets the requirements set
forth in the Offering Memorandum for eligibility to participate in the Offering.

        (g) "EMPLOYEE" means any person, including Officers and Directors,
employed by the Company or an Affiliate of the Company. Neither service as a
Director nor payment of a director's fee shall be sufficient to constitute
"employment" by the Company or the Affiliate.

        (h) "EXCHANGE ACT" means the United States Securities Exchange Act of
1934, as amended.

        (i) "FAIR MARKET VALUE" means the value of a security, as determined in
good faith by the Board. If the security is listed on the New York Stock
Exchange or any other established stock exchange or traded on the Nasdaq
National Market or the Nasdaq SmallCap Market, then, except as otherwise
provided in the Offering Memorandum, the Fair Market Value of the security shall
be the closing sales price (rounded up where necessary to the nearest whole
cent) for such security (or the closing bid, if no sales were reported) as
quoted on such exchange or

<PAGE>   2

market (or, in the event that the security is traded on more than one such
exchange or market, the exchange or market with the greatest volume of trading
in the relevant security of the Company) on the trading day occurring on or
closest to the relevant determination date, as reported in The Wall Street
Journal or such other source as the Board deems reliable, and on the date as
determined more precisely in the Offering Memorandum.

        (j) "NON-EMPLOYEE DIRECTOR" means a Director who either (i) is not a
current Employee or Officer of the Company or its parent or subsidiary, does not
receive compensation (directly or indirectly) from the Company or its parent or
subsidiary for services rendered as a consultant or in any capacity other than
as a Director (except for an amount as to which disclosure would not be required
under Item 404(a) of Regulation S-K promulgated pursuant to the Securities Act
("Regulation S-K")), does not possess an interest in any other transaction as to
which disclosure would be required under Item 404(a) of Regulation S-K, and is
not engaged in a business relationship as to which disclosure would be required
under Item 404(b) of Regulation S-K; or (ii) is otherwise considered a
"non-employee director" for purposes of Rule 16b-3.

        (k) "OFFERING" means the grant of Rights to purchase Shares under the
Plan to Eligible Employees.

        (l) "OFFERING DATE" means a date selected by the Board for an Offering
to commence.

        (m) "OFFERING MEMORANDUM" means a memorandum describing the terms of the
then current or otherwise relevant Offering.

        (n) "PARTICIPANT" means an Eligible Employee who holds an outstanding
Right granted pursuant to the Plan or, if applicable, such other person who
holds an outstanding Right granted under the Plan.

        (o) "PLAN" means this Non-Qualified Employee Stock Purchase Plan.

        (p) "PURCHASE DATE" means one or more dates established by the Board
during an Offering on which Rights granted under the Plan shall be exercised and
purchases of Shares carried out in accordance with such Offering.

        (q) "RIGHT" means an option to purchase Shares granted pursuant to the
Plan.

        (r) "RULE 16b-3" means Rule 16b-3 of the Exchange Act or any successor
to Rule 16b-3 as in effect with respect to the Company at the time discretion is
being exercised regarding the Plan.

        (s) "SECURITIES ACT" means the United States Securities Act of 1933, as
amended.

        (t) "SHARE" means a share of the common stock of the Company.

                                       2

<PAGE>   3

3.      ADMINISTRATION.

        (a) The Board shall administer the Plan unless and until the Board
delegates administration to a Committee, as provided in subsection 3(c). Whether
or not the Board has delegated administration, the Board shall have the final
power to determine all questions of policy and expediency that may arise in the
administration of the Plan.

        (b) The Board (or the Committee) shall have the power, subject to, and
within the limitations of, the express provisions of the Plan:

               (i) To determine when and how Rights to purchase Shares shall be
granted and the provisions of each Offering of such Rights (which need not be
identical).

               (ii) To designate from time to time which Affiliates of the
Company shall be eligible to participate in the Plan.

               (iii) To designate from time to time which Employees are Eligible
Employees.

               (iv) To construe and interpret the Plan and Rights granted under
it, and to establish, amend and revoke rules and regulations for its
administration. The Board, in the exercise of this power, may correct any
defect, omission or inconsistency in the Plan, in a manner and to the extent it
shall deem necessary or expedient to make the Plan fully effective.

               (v) To amend the Plan as provided in Section 14.

               (vi) Generally, to exercise such powers and to perform such acts
as it deems necessary or expedient to promote the best interests of the Company
and its Affiliates.

        (c) The Board may delegate administration of the Plan to a Committee of
the Board composed of two (2) or more members, all of the members of which
Committee may be, in the discretion of the Board, Non-Employee Directors. If
administration is delegated to a Committee, the Committee shall have, in
connection with the administration of the Plan, the powers theretofore possessed
by the Board, including the power to delegate to a subcommittee of two (2) or
more Non-Employee Directors any of the administrative powers the Committee is
authorized to exercise (and references in this Plan to the Board shall
thereafter be to the Committee or such a subcommittee), subject, however, to
such resolutions, not inconsistent with the provisions of the Plan, as may be
adopted from time to time by the Board. The Board may abolish the Committee at
any time and revest in the Board the administration of the Plan.

4.      SHARES SUBJECT TO THE PLAN.

        (a) Subject to the provisions of Section 13 relating to adjustments upon
changes in securities, the Shares that may be sold pursuant to Rights granted
under the Plan shall not exceed in the aggregate Seven Hundred Fifty Thousand
(750,000) Shares. If any Right granted under the Plan shall for any reason
terminate without having been exercised, the Shares not purchased under such
Right shall again become available for the Plan.

        (b) The Shares subject to the Plan may be unissued Shares or Shares that
have been bought on the open market at prevailing market prices or otherwise.

                                       3

<PAGE>   4

5.      GRANT OF RIGHTS; OFFERING.

        (a) The Board may from time to time grant or provide for the grant of
Rights to purchase Shares under the Plan to Eligible Employees in an Offering on
one or more Offering Dates selected by the Board. Each Offering shall be in such
form and shall contain such terms and conditions as the Board shall deem
appropriate. The terms and conditions of an Offering shall be incorporated by
reference into the Plan and treated as part of the Plan. The provisions of
separate Offerings need not be identical, but each Offering shall include
(through incorporation of the provisions of this Plan by reference in the
Offering Memorandum or otherwise) the period during which the Offering shall be
effective, which period shall not exceed twenty-seven (27) months beginning with
the Offering Date, and the substance of the provisions contained in Sections 6
through 9, inclusive.

        (b) If a Participant has more than one Right outstanding under the Plan,
unless he or she otherwise indicates in agreements or notices delivered
hereunder: (i) each agreement or notice delivered by that Participant will be
deemed to apply to all of his or her Rights under the Plan, and (ii) an
earlier-granted Right (or a Right with a lower exercise price, if two Rights
have identical grant dates) will be exercised to the fullest possible extent
before a later-granted Right (or a Right with a higher exercise price if two
Rights have identical grant dates) will be exercised.

6.      ELIGIBILITY.

        (a) Rights may be granted only to Employees of the Company or, as the
Board may designate as provided in subsection 3(b), to Employees one or more
Affiliates. Except as provided in subsection 6(b), an Employee shall not be
eligible to be granted Rights under the Plan unless, on the Offering Date, such
Employee has been in the employ of the Company or the Affiliate, as the case may
be, for such continuous period preceding such grant as the Board may require.

        (b) The Board may provide that each person who, during the course of an
Offering, first becomes an Eligible Employee will, on a date or dates specified
in the Offering Memorandum which coincides with the day on which such person
becomes an Eligible Employee or which occurs thereafter, receive a Right under
that Offering, which Right shall thereafter be deemed to be a part of that
Offering. Such Right shall have the same characteristics as any Rights
originally granted under that Offering, as described herein, except that, unless
otherwise determined by the Board:

               (i) the date on which such Right is granted shall be the
"Offering Date" of such Right for all purposes, including determination of the
exercise price of such Right;

               (ii) the period of the Offering with respect to such Right shall
begin on its Offering Date and end coincident with the end of such Offering; and

               (iii) the Board may provide that if such person first becomes an
Eligible Employee within a specified period of time before the end of the
Offering, he or she will not receive any Right under that Offering.

                                       4

<PAGE>   5

        (c) Unless otherwise specified in an Offering Memorandum, no Employee
shall be eligible for the grant of any Rights under the Plan if, immediately
after any such Rights are granted, such Employee owns stock possessing five
percent (5%) or more of the total combined voting power or value of all classes
of stock of the Company or of any Affiliate. For purposes of this subsection
6(c), the rules of Section 424(d) of the United States Internal Revenue Code of
1986, as amended (the "Code"), shall apply in determining the stock ownership of
any Employee, and stock which such Employee may purchase under all outstanding
rights and options shall be treated as stock owned by such Employee.

        (d) Unless otherwise specified in an Offering Memorandum, an Eligible
Employee may be granted Rights under the Plan only if such Rights, together with
any other Rights granted under all employee stock purchase plans of the Company
and any Affiliates, as specified by Section 423(b)(8) of the Code, do not permit
such Eligible Employee's rights to purchase Shares or shares of any Affiliate to
accrue at a rate which exceeds twenty five thousand dollars ($25,000) of the
fair market value of such Shares (determined at the time such Rights are
granted) for each calendar year in which such Rights are outstanding at any
time.

7. RIGHTS; PURCHASE PRICE.

        (a) On each Offering Date, each Eligible Employee, pursuant to an
Offering made under the Plan, shall be granted the Right to purchase up to the
number of Shares purchasable either:

               (i) with a minimum and maximum percentage or percentages
designated by the Board (which need not be uniform throughout the Offering, but
any fluctuations in such percentages shall be applied equally to all Employees
participating in the Offering) not exceeding twenty percent (20%) of such
Employee's Earnings (as defined by the Board in each Offering) during the period
which begins on the Offering Date (or such later date as the Board determines
for a particular Offering) and ends on the date stated in the Offering, which
date shall be no later than the end of the Offering, which amount shall, as
specified in the Offering Memorandum for that Offering, be (1) withheld, in
whole or in part, from such Employee's Earnings during the period which begins
on the Offering Date (or such later date as the Board determines for a
particular Offering) and ends on the date stated in the Offering Memorandum for
that Offering, which date shall be no later than the end of the Offering and/or
(2) contributed in whole or in part by such Employee during such Offering, or

               (ii) with a maximum dollar amount designated by the Board that,
as the Board determines for a particular Offering, (1) shall be withheld, in
whole or in part, from such Employee's Earnings (as defined by the Board in each
Offering Memorandum) during the period which begins on the Offering Date (or
such later date as the Board determines for a particular Offering) and ends on
the date stated in the Offering, which date shall be no later than the end of
the Offering and/or (2) shall be contributed, in whole or in part, by such
Employee during such period.

        (b) The Board shall establish one or more Purchase Dates during an
Offering on which Rights granted under the Plan shall be exercised and purchases
of Shares carried out in accordance with such Offering.

                                       5

<PAGE>   6

        (c) In connection with each Offering made under the Plan, the Board may
specify a maximum amount of Shares that may be purchased by any Participant as
well as a maximum aggregate amount of Shares that may be purchased by all
Participants pursuant to such Offering. In addition, in connection with each
Offering that contains more than one Purchase Date, the Board may specify a
maximum aggregate amount of Shares which may be purchased by all Participants on
any given Purchase Date under the Offering. If the aggregate purchase of Shares
upon exercise of Rights granted under the Offering would exceed any such maximum
aggregate amount, the Board shall make a pro rata allocation of the Shares
available in as nearly a uniform manner as shall be practicable and as it shall
deem to be equitable.

        (d) Unless otherwise determined by the Board, the purchase price of
Shares acquired pursuant to Rights granted under the Plan shall be not less than
the lesser of:

               (i) an amount equal to eighty-five percent (85%) of the fair
market value of the Shares on the Offering Date; or

               (ii) an amount equal to eighty-five percent (85%) of the fair
market value of the Shares on the Purchase Date.

8.      PARTICIPATION; WITHDRAWAL; TERMINATION.

        (a) An Eligible Employee may become a Participant in the Plan pursuant
to an Offering by delivering an enrollment form to the Company within the time
specified in the Offering Memorandum, in such form as the Company provides. Each
such agreement shall authorize payroll deductions of up to the maximum
percentage specified by the Board of such Employee's Earnings during the
Offering (as defined in each Offering). The payroll deductions made for each
Participant shall be credited to a bookkeeping account for such Participant
under the Plan and either may be deposited with the general funds of the Company
or may be deposited in a separate account in the name of, and for the benefit
of, such Participant with a financial institution designated by the Company. To
the extent provided in the Offering, a Participant may reduce (including to
zero) or increase such payroll deductions. To the extent provided in the
Offering, a Participant may begin such payroll deductions after the beginning of
the Offering. A Participant may make additional payments into his or her account
only if specifically provided for in the Offering Memorandum and only if the
Participant has not already had the maximum permitted amount withheld during the
Offering.

        (b) At any time during an Offering, a Participant may terminate his or
her payroll deductions under the Plan and withdraw from the Offering by
delivering to the Company a notice of withdrawal in such form as the Company
provides. Such withdrawal may be elected at any time prior to the end of the
Offering except as provided by the Board in the Offering Memorandum. Upon such
withdrawal from the Offering by a Participant, the Company shall distribute to
such Participant all of his or her accumulated payroll deductions (reduced to
the extent, if any, such deductions have been used to acquire Shares for the
Participant) under the Offering, without interest unless otherwise specified in
the Offering Memorandum, and such Participant's interest in that Offering shall
be automatically terminated. A Participant's withdrawal from an Offering will
have no effect upon such Participant's eligibility to participate

                                       6

<PAGE>   7

in any other Offerings under the Plan but such Participant will be required to
deliver a new participation agreement in order to participate in subsequent
Offerings under the Plan.

        (c) Rights granted pursuant to any Offering under the Plan shall
terminate immediately upon cessation of any participating Employee's employment
with the Company and its designated Affiliates for any reason (subject to any
post-employment participation period required by law) or other lack of
eligibility. The Company shall distribute to such terminated Employee all of his
or her accumulated payroll deductions (reduced to the extent, if any, such
deductions have been used to acquire Shares for the terminated Employee) under
the Offering, without interest unless otherwise specified in the Offering
Memorandum. If the accumulated payroll deductions have been deposited with the
Company's general funds, then the distribution shall be made from the general
funds of the Company, without interest. If the accumulated payroll deductions
have been deposited in a separate account with a financial institution as
provided in subsection 8(a), then the distribution shall be made from the
separate account, without interest unless otherwise specified in the Offering
Memorandum.

        (d) Rights granted under the Plan shall not be transferable by a
Participant otherwise than by will or the laws of descent and distribution, or
by a beneficiary designation as provided in Section 15 and, otherwise during his
or her lifetime, shall be exercisable only by the person to whom such Rights are
granted.

9.      EXERCISE.

        (a) On each Purchase Date specified in the relevant Offering Memorandum,
each Participant's accumulated payroll deductions and other additional payments
specifically provided for in the Offering (without any increase for interest)
will be applied to the purchase of Shares up to the maximum amount of Shares
permitted pursuant to the terms of the Plan and the applicable Offering, at the
purchase price specified in the Offering Memorandum for that Offering. No
fractional Shares shall be issued upon the exercise of Rights granted under the
Plan unless specifically provided for in the Offering and permitted by law.

        (b) As no fractional Shares shall be issued upon the exercise of Rights,
unless otherwise specifically provided in the Offering Memorandum, the amount,
if any, of accumulated payroll deductions remaining in any Participant's account
on the final Purchase Date of the Offering after the purchase of the whole
Shares pursuant to subsection 9(a) shall be distributed in full to the
Participant at the end of the Offering, without interest. If the accumulated
payroll deductions have been deposited with the Company's general funds, then
the distribution shall be made from the general funds of the Company, without
interest. If the accumulated payroll deductions have been deposited in a
separate account with a financial institution as provided in subsection 8(a),
then the distribution shall be made from the separate account, without interest
unless otherwise specified in the Offering.

        (c) The amount, if any, of accumulated payroll deductions remaining in
any Participant's account after the purchase of Shares that is less than the
amount required to purchase one whole Share on the final Purchase Date of the
Offering shall be carried forward, without interest, into the next Offering.

                                       7

<PAGE>   8

        (d) No Rights granted under the Plan may be exercised to any extent
unless the Shares to be issued upon such exercise under the Plan (including
Rights granted thereunder) are covered by an effective registration statement
pursuant to the Securities Act and the Plan is in material compliance with all
applicable state, foreign and other securities and other laws applicable to the
Plan. If on a Purchase Date in any Offering hereunder the Shares are not so
registered or the Plan is not in such compliance, no Rights granted under the
Plan or any Offering shall be exercised on such Purchase Date, and the Purchase
Date shall be delayed until the Shares are subject to such an effective
registration statement and the Plan is in such compliance, except that the
Purchase Date shall not be delayed more than twelve (12) months and the Purchase
Date shall in no event be more than twenty-seven (27) months from the Offering
Date. If, on the Purchase Date of any Offering hereunder, as delayed to the
maximum extent permissible, the Shares are not registered and the Plan is not in
such compliance, no Rights granted under the Plan or any Offering shall be
exercised and all payroll deductions accumulated during the Offering (reduced to
the extent, if any, such deductions have been used to acquire Shares) shall be
distributed to the Participants, without interest unless otherwise specified in
the Offering Memorandum. If the accumulated payroll deductions have been
deposited with the Company's general funds, then the distribution shall be made
from the general funds of the Company, without interest. If the accumulated
payroll deductions have been deposited in a separate account with a financial
institution as provided in subsection 8(a), then the distribution shall be made
from the separate account, without interest unless otherwise specified in the
Offering Memorandum.

10.     COVENANTS OF THE COMPANY.

        (a) During the terms of the Rights granted under the Plan, the Company
shall ensure that the amount of Shares required to satisfy such Rights are
available.

        (b) The Company shall seek to obtain from each federal, state, foreign
or other regulatory commission or agency having jurisdiction over the Plan such
authority as may be required to issue and sell Shares upon exercise of the
Rights granted under the Plan. If, after reasonable efforts, the Company is
unable to obtain from any such regulatory commission or agency the authority
which counsel for the Company deems necessary for the lawful issuance and sale
of Shares under the Plan, the Company shall be relieved from any liability for
failure to issue and sell Shares upon exercise of such Rights unless and until
such authority is obtained.

11.     USE OF PROCEEDS FROM SHARES.

        Proceeds from the sale of Shares pursuant to Rights granted under the
Plan shall constitute general funds of the Company.

12.     RIGHTS AS A STOCKHOLDER AND EMPLOYEE.

        (a) A Participant shall not be deemed to be the holder of, or to have
any of the rights of a holder with respect to, Shares subject to Rights granted
under the Plan unless and until the Participant's Shares acquired upon exercise
of Rights under the Plan are recorded in the books of the Company.

                                       8

<PAGE>   9

        (b) Neither the Plan nor the grant of any Right thereunder shall confer
any right on any Employee to remain in the employ of the Company or any
Affiliate or restrict the right of the Company or any Affiliate to terminate
such Employee's employment.

13.     ADJUSTMENTS UPON CHANGES IN SECURITIES.

        (a) Subject to any required action by the stockholders of the Company,
the number of Shares covered by each Right under the Plan that has not yet been
exercised and the number of Shares that have been authorized for issuance under
the Plan but have not yet been placed under a Right (collectively, the
"Reserves"), as well as the price per Share covered by each Right under the Plan
that has not yet been exercised, shall be proportionately adjusted for any
increase or decrease in the number of issued Shares resulting from a stock split
or the payment of stock dividend (but only on the Common Stock) or any other
increase or decrease in the number of Shares effected without receipt of
consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected
without receipt of consideration." Such adjustment shall be made by the Board,
whose determination in that respect shall be final, binding and conclusive.
Except as expressly provided herein, no issue by the Company of shares of stock
of any class, or securities convertible into shares of stock of any class, shall
affect, and no adjustment by reason thereof shall be made with respect to, the
number or price of Shares subject to a Right.

        (b) In the event of the proposed dissolution or liquidation of the
Company, any and all Offerings shall terminate immediately prior to the
consummation of such proposed action, unless otherwise provided by the Board.
The Board may, in the exercise of its sole discretion in such instances, declare
that the Rights under the Plan shall terminate as of a date fixed by the Board
and give each Participant the right to exercise his or her Right. In the event
of a proposed sale of all or substantially all of the assets of the Company, or
the merger or consolidation of the Company with or into another corporation or a
parent or subsidiary of such successor corporation when the Company is not the
surviving corporation, or a reverse merger in which the Company is the surviving
corporation but the Shares outstanding immediately preceding the merger are
converted by virtue of the merger into other property, whether in the form of
securities, cash or otherwise, any and all Offerings shall terminate immediately
prior to the consummation of such proposed action, unless otherwise provided by
the Board. The Board may, in the exercise of its sole discretion in such
instances, and in lieu of assumption or substitution of the Rights, provide that
each Participant shall have the right to exercise his or her Right. If the Board
makes a Right exercisable in lieu of assumption or substitution in the event of
a merger or sale of assets, the Board shall notify the Participant that the
Right shall be fully exercisable for a period of twenty (20) days from the date
of such notice (or such other period of time as the Board shall determine), and
the Right shall terminate upon the expiration of such period.

        (c) The Board may, if it so determines in the exercise of its sole
discretion, also make provision for adjusting the Reserves, as well as the price
per Share covered by each outstanding Right, in the event that the Company
effects one or more reorganizations, recapitalizations, rights offering, or
other increases or reductions of outstanding Shares, and in the event of the
Company being consolidated with or merged into any other corporation.

                                       9

<PAGE>   10

14.     AMENDMENT OF THE PLAN.

        (a) The Board at any time, and from time to time, may amend the Plan.

        (b) It is expressly contemplated that the Board may amend the Plan in
any respect the Board deems necessary or advisable to comply with applicable
law.

        (c) Rights and obligations under any Rights granted before amendment of
the Plan shall not be impaired by any amendment of the Plan without the consent
of the person to whom such Rights were granted, or except as necessary to comply
with any laws or governmental regulations.

15.     DESIGNATION OF BENEFICIARY.

        (a) A Participant may file a written designation of a beneficiary who is
to receive any Shares and/or cash, if any, from the Participant's account under
the Plan in the event of such Participant's death subsequent to the end of an
Offering but prior to delivery to the Participant 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 during an Offering.

        (b) The Participant may change such designation of beneficiary at any
time by written notice. In the event of the death of a Participant and in the
absence of a beneficiary validly designated under the Plan 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 sole 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.

16.     TERMINATION OR SUSPENSION OF THE PLAN.

        (a) The Board in its discretion may suspend or terminate the Plan at any
time. Unless sooner terminated, the Plan shall terminate at the time that all of
the Shares available for issuance under the Plan, as increased and/or adjusted
from time to time, have been issued under the terms of the Plan. No Rights may
be granted under the Plan while the Plan is suspended or after it is terminated.

        (b) Rights and obligations under any Rights granted while the Plan is in
effect shall not be impaired by suspension or termination of the Plan, except as
expressly provided in the Plan (including any Offering Memorandum) or with the
consent of the person to whom such Rights were granted, or except as necessary
to comply with any laws or governmental regulation.

17.     TAX WITHHOLDING AND OTHER TAXES AND CONTRIBUTIONS

        (a) The Company and any Affiliate whose Employees are Eligible Employees
shall withhold from each Participant's earnings or other amounts payable to the
Participant income

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<PAGE>   11

tax, social security taxes and other taxes required or, if the Company or such
Affiliate so chose, permitted, to be withheld with respect to such amounts under
applicable law. The Participant shall be liable for all such amounts. In the
event the Company or an Affiliate does not withhold such taxes or a
Participant's earnings are insufficient to satisfy such withholding, the Company
or an Affiliate shall have the right to effect the sale of such Participant's
Shares on behalf of the Participant and pay the proceeds to the Company or to
the Affiliate, retain amounts that have been deducted from payroll and would
otherwise be used to purchase Shares, withhold such taxes from amounts otherwise
due to the Participant, or take any other action that they deem necessary to
cause the Participant to fulfill such obligation.

        (b) It is a condition of the grant of Rights to a Participant under the
Plan that the Participant agrees to indemnify the Company and its Affiliates in
respect of any secondary national insurance contributions payable by any of them
on the exercise of the Option. Accordingly, no Right may be exercised under the
Plan until the Participant has put the Company or the relevant Affiliate (as the
case may be) in sufficient funds (which shall be determined by the Company or
the relevant Affiliate (as appropriate)) to meet any obligation of the Company
or the relevant Affiliate to account for income tax chargeable under the PAYE
system or national insurance contributions (both primary and secondary,
including, for the avoidance of doubt, amounts covered by the indemnity in this
Section 17(b)). The Company or the relevant Affiliate (as appropriate) may, in
lieu of the Participant providing cash funds to the relevant company, sell at
the best price which it can reasonably obtain such number of Shares allotted to
the Participant as will provide it with an amount necessary to discharge the
Participant's obligation under this Section 17(b).

        (c) The Company or the relevant Affiliate (as appropriate) shall use
reasonable endeavours (with the Participant's assistance if required) to agree
with the United Kingdom Inland Revenue the amount of any such income tax or
national insurance contributions in advance of any Shares being issued to
Participant following the exercise of Rights. In the event that any funds made
available are less than or greater than the amount needed to meet any obligation
of the relevant company to account for income tax or other amounts that are
chargeable under the PAYE system and national insurance contributions in
relation to the exercise of the relevant Rights, an appropriate payment shall be
made by the Participant to the relevant company, or vice versa, as appropriate.

18.     EFFECTIVE DATE OF PLAN.

        The Plan shall become effective upon adoption by the Board.

NON-QUALIFIED EMPLOYEE STOCK PURCHASE PLAN HISTORY

        Adopted July 13, 2001.

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