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                                                                   Exhibit 10.18

                               IMMUNEX CORPORATION
                        1999 EMPLOYEE STOCK PURCHASE PLAN
                    As Amended and Restated on April 25, 2000

SECTION 1.  PURPOSE

     The purposes of the Immunex Corporation 1999 Employee Stock Purchase Plan
(the "Plan") are (a) to assist employees of Immunex Corporation, a Washington
corporation (the "Company"), and its designated subsidiaries in acquiring a
stock ownership interest in the Company pursuant to a plan that is intended to
qualify as an "employee stock purchase plan" under Section 423 of the Internal
Revenue Code of 1986, as amended, and (b) to encourage employees to remain in
the employ of the Company and its subsidiaries.

SECTION 2.  DEFINITIONS

     For purposes of the Plan, the following terms shall be defined as set forth
below.

     "Board" means the Board of Directors of the Company.

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

     "Committee" means the Company's Compensation Committee.

     "Common Stock" means the common stock, par value $0.01 per share, of the
Company.

     "Company" means Immunex Corporation, a Washington corporation.

     "Designated Subsidiary" has the meaning set forth under the definition of
"Eligible Employee" in this Section 2.

     "Eligible Compensation" means all salary and wages including overtime.
Regular cash compensation does not include cash bonuses, commissions, severance
pay, hiring and relocation bonuses, pay in lieu of vacations, sick leave, gain
from stock option exercises or any other special payments.

     "Eligible Employee" means any employee of the Company or any domestic
Subsidiary Corporation or any other Subsidiary Corporation designated by the
Board or the Committee (each a "Designated Subsidiary"), who is in the employ of
the Company (or any Designated Subsidiary) on one or more Offering Dates and who
meets the following criteria:

          (a)  the employee does not, immediately after the option is granted,
               own stock (as defined by the Code) possessing 5% or more of the
               total combined voting power or value of all classes of stock of
               the Company or of a Parent Corporation or Subsidiary Corporation
               of the Company;

          (b)  the employee's customary employment is for 20 hours or more per
               week; provided, however, that the Plan Administrator may increase
               or decrease this minimum requirement for any future Offering so
               long as the maximum number of hours does not exceed 20 hours;

          (c)  if specified by the Plan Administrator for future Offerings,
               minimum requirements for customary employment of a maximum of
               five months per year;

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         (d)      the employee has been employed for at least three months as of
                  the Offering Date; provided, however, if specified by the Plan
                  Administrator for any future Offering, a minimum employment
                  period that does not exceed two years; and

         (e)      the employee is not a highly compensated employee. For
                  purposes of the Plan, a "highly compensated employee" is any
                  employee of the Company or a Designated Subsidiary who has a
                  base salary in excess of $175,000 per year; provided, however,
                  that the Plan Administrator may increase or decrease this
                  amount for any future Offering within the limitations imposed
                  by Code Section 423.

If the Company permits any employee of a Designated Subsidiary to participate in
the Plan, then all employees of that Designated Subsidiary who meet the
requirements of this paragraph shall also be considered Eligible Employees.

     "Enrollment Period" has the meaning set forth in Section 7.1.

     "ESPP Broker" has the meaning set forth in Section 10.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended.

     "Offering" has the meaning set forth in Section 5.1.

     "Offering Date" means the first day of an Offering.

     "Option" means an option granted under the Plan to an Eligible Employee to
purchase shares of Common Stock.

     "Parent Corporation" means any corporation, other than the Company, in an
unbroken chain of corporations ending with the Company, if, at the time of the
granting of the Option, each of the corporations, other than the Company, owns
stock possessing 50% or more of the total combined voting power of all classes
of stock in one of the other corporations in such chain.

     "Participant" means any Eligible Employee who has elected to participate in
an Offering in accordance with the procedures set forth in Section 7.1 and who
has not withdrawn from the Plan or whose participation in the Plan is not
terminated.

     "Plan" means the Immunex Corporation 1999 Employee Stock Purchase Plan.

     "Purchase Date" means the last day of each Purchase Period.

     "Purchase Period" has the meaning set forth in Section 5.2.

     "Purchase Price" has the meaning set forth in Section 6.

     "Subscription" has the meaning set forth in Section 7.1.

     "Subsidiary Corporation" means any corporation, other than the Company, in
an unbroken chain of corporations beginning with the Company, if, at the time of
the granting of the Option, each of the corporations, other than the last
corporation in the unbroken chain, owns stock possessing 50% or more of the
total combined voting power of all classes of stock in one of the other
corporations in such chain.

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SECTION 3.  ADMINISTRATION

              3.1    Plan Administrator

     The Plan shall be administered by the Board or the Committee or, if and to
the extent the Board or the Committee designates an executive officer of the
Company to administer the Plan, by such executive officer (each, the "Plan
Administrator"). Any decisions made by the Plan Administrator shall be
applicable equally to all Eligible Employees.

              3.2    Administration and Interpretation by the Plan Administrator

     Subject to the provisions of the Plan, the Plan Administrator shall have
the authority, in its sole discretion, to determine all matters relating to
Options granted under the Plan, including all terms, conditions, restrictions
and limitations of Options; provided, however, that all Participants granted
Options pursuant to the Plan shall have the same rights and privileges within
the meaning of Code Section 423. The Plan Administrator shall also have
exclusive authority to interpret the Plan and may from time to time adopt, and
change, rules and regulations of general application for the Plan's
administration. The Plan Administrator's interpretation of the Plan and its
rules and regulations, and all actions taken and determinations made by the Plan
Administrator pursuant to the Plan, unless reserved to the Board or the
Committee, shall be conclusive and binding on all parties involved or affected.
The Plan Administrator may delegate administrative duties to such of the
Company's other officers or employees as the Plan Administrator so determines.

SECTION 4.  STOCK SUBJECT TO PLAN

     Subject to adjustment from time to time as provided in Section 20, the
maximum number of shares of Common Stock which shall be available for issuance
under the Plan shall be 3,000,000/6/ shares. Shares issued under the Plan shall
be drawn from authorized and unissued shares or shares now held or subsequently
acquired by the Company.

SECTION 5.  OFFERING DATES

     5.1      Offerings

     (a)      Except as otherwise set forth below, the Plan shall be implemented
by a series of Offerings (each, an "Offering"). Offerings shall commence on May
1 and November 1 of each year and end on the next October 31 and April 30,
respectively, occurring thereafter (each, an "Offering"); provided, however,
that the first Offering shall begin on July 1, 1999 and shall end on October 31,
1999.

     (b)      Notwithstanding the foregoing, the Plan Administrator may
establish (i) a different term for one or more Offerings and (ii) different
commencing and ending dates for such Offerings; provided, however, that an
Offering may not exceed five years; and provided, further, that if the Purchase
Price may be less than 85% of the fair market value of the Common Stock on the
Purchase Date, the Offering may not exceed one year.

     (c)      In the event the first or the last day of an Offering is not a
regular business day, then the first day of the Offering shall be deemed to be
the next regular business day and the last day of the Offering shall be deemed
to be the last preceding regular business day.

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     /6/ The original number of shares of Common Stock in the Plan was 500,00.
This was adjusted to 3,000,000as a resulted of a 2-for-1 stock split on August
26, 1999 and a split March 20 2000

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         5.2      Purchase Periods

         (a)      Each Offering shall consist of one or more consecutive
purchase periods (each, a "Purchase Period"). The last day of each Purchase
Period shall be the Purchase Date for such Purchase Period. Except as otherwise
set forth below, each Purchase Period shall commence on May 1 and November 1 of
each year and end on the next October 31 and April 30, respectively, occurring
thereafter; provided, however, that the Purchase Period for the first Offering
shall begin on July 1, 1999 and shall end on October 31, 1999.

         (b)      Notwithstanding the foregoing, the Board may establish (i) a
different term for one or more Purchase Periods and (ii) different commencing
and ending dates for any such Purchase Period.

         (c)      In the event the first or last day of a Purchase Period is not
a regular business day, then the first day of the Purchase Period shall be
deemed to be the next regular business day and the last day of the Purchase
Period shall be deemed to be the last preceding regular business day.

         5.3      Governmental Approval; Shareholder Approval

         Notwithstanding any other provision of the Plan to the contrary, an
Option granted pursuant to the Plan shall be subject to (a) obtaining all
necessary governmental approvals and qualifications of the Plan and of the
issuance of Options and sale of Common Stock pursuant to the Plan and (b)
obtaining shareholder approval of the Plan.

SECTION 6.  PURCHASE PRICE

         The purchase price (the "Purchase Price") at which Common Stock may be
acquired in an Offering pursuant to the exercise of all or any portion of an
Option granted under the Plan (the "Offering Exercise Price") shall be 85% of
the lesser of (a) the fair market value of the Common Stock on the Offering Date
of such Offering and (b) the fair market value of the Common Stock on the
Purchase Date. The fair market value of the Common Stock on the Offering Date or
on the Purchase Date shall be the closing price for the Common Stock as reported
for such day by the Nasdaq Stock Market, the New York Stock Exchange or other
trading market on which the Company's Common Stock may then be traded (the
"Exchange"). If no sales of the Common Stock were made on the Exchange on such
day, fair market value shall mean the closing price for the Common Stock as
reported for the next preceding day on which sales of the Stock were made on the
Exchange. If the Common Stock is not listed on an Exchange, the Board shall
designate an alternative method of determining the fair market value of the
Common Stock.

SECTION 7.  PARTICIPATION IN THE PLAN

         7.1      Initial Participation

         An Eligible Employee shall become a Participant on the first Offering
Date after satisfying the eligibility requirements and delivering to the Plan
Administrator during the enrollment period established by the Plan Administrator
(the "Enrollment Period") a subscription (the "Subscription"):

         (a)      indicating the Eligible Employee's election to participate in
the Plan;

         (b)      authorizing payroll deductions and stating the amount to be
deducted regularly from the Participant's pay; and

         (c)      authorizing the purchase of Common Stock for the Participant
in each Purchase Period.

         An Eligible Employee who does not deliver a Subscription as provided
above during the Enrollment Period shall not participate in the Plan for that
Offering or for any subsequent Offering unless such Eligible

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Employee subsequently enrolls in the Plan by filing a Subscription with the
Company during the Enrollment Period for such subsequent Offering. The Company
may, from time to time, change the Enrollment Period for any future Offering as
deemed advisable by the Plan Administrator, in its sole discretion, for the
proper administration of the Plan.

         Except as provided in Section 7.2, an employee who becomes eligible to
participate in the Plan after an Offering has commenced shall not be eligible to
participate in such Offering but may participate in any subsequent Offering,
provided that such employee is still an Eligible Employee as of the commencement
of any such subsequent Offering. Eligible Employees may not participate in more
than one Offering at a time.

         7.2      Alternative Initial Participation

         Notwithstanding any other provisions of the Plan, the Board or the
Committee may provide for any future Offering that any employee of the Company
or any Designated Subsidiary who first meets the requirements of subparagraphs
(a) through (c) of the paragraph "Eligible Employee" in Section 2 during the
course of an Offering shall, on a date or dates specified in the Offering which
coincides with the day on which such person first meets such requirements or
occurs on a specified date thereafter, receive an Option under that Offering
which Option shall thereafter be deemed to be a part of that Offering. Such
Option shall have the same characteristics as any Options originally granted
under that Offering, except that:

         (i)      the date on which such Option is granted shall be the
                  "Offering Date" of such Option for all purposes, including
                  determining the Purchase Price of such Option; provided,
                  however, that if the fair market value of the Common Stock on
                  the date on which such Option is granted is less than the fair
                  market value of Common Stock on the first day of the Offering,
                  then, solely for the purpose of determining the Purchase Price
                  of such Option, the first day of the Offering shall be the
                  "Offering Date" for such Option;

         (ii)     the Purchase Period(s) for such Option shall begin on its
                  Offering Date and end coincident with the remaining Purchase
                  Date(s) for such Offering; and


         (iii)    the Board or the Committee may provide that if such person
                  first meets such requirements within a specified period of
                  time before the end of a Purchase Period for such Offering, he
                  or she will not receive any Option for that Purchase Period.

         7.3      Continued Participation

         A Participant shall automatically participate in the next Offering
until such time as such Participant withdraws from the Plan pursuant to Section
11.1 or 11.2 or terminates employment as provided in Section 12.

SECTION 8.  LIMITATIONS ON RIGHT TO PURCHASE SHARES

         8.1      Number of Shares Purchased

         The maximum number of shares of stock that may be offered to a
Participant on any Offering Date shall be equal to $15,000 divided by the fair
market value of one share of Common Stock of the Company on the applicable
Offering Date. Further, no Participant shall be entitled to purchase Common
Stock under the Plan (or any other employee stock purchase plan that is intended
to meet the requirements of Code Section 423 sponsored by the Company, a Parent
Corporation or a Subsidiary Corporation) with a fair market value exceeding
$15,000, determined as of the Offering Date for each Offering (or such other
limit as may be imposed by the Code), in any calendar year in which a
Participant participates in the Plan (or other employee stock purchase plan
described in this Section 8.1). For any future Offering, the Board or the
Committee may specify a maximum number of shares which may be purchased by any
Participant as well as a maximum aggregate number of shares which may be
purchased by all Participants pursuant to such Offering. In addition, for any

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future Offering with more than one Purchase Date, the Board or the Committee may
specify a maximum aggregate number of shares which may be purchased by all
Participants on any given Purchase Date under the Offering.

         8.2      Pro Rata Allocation

         In the event the number of shares of Common Stock that might be
purchased by all Participants in the Plan exceeds the number of shares of Common
Stock available in the Plan, the Plan Administrator shall make a pro rata
allocation of the remaining shares of Common Stock in as uniform a manner as
shall be practicable and as the Plan Administrator shall determine to be
equitable. Fractional shares may not be issued under the Plan unless the Plan
Administrator determines otherwise for any future Offering.

SECTION 9.  PAYMENT OF PURCHASE PRICE

         9.1      General Rules

         Subject to Section 9.12, Common Stock that is acquired pursuant to the
exercise of all or any portion of an Option may be paid for only by means of
payroll deductions from the Participant's Eligible Compensation. Except as set
forth in this Section 9, the amount of compensation to be withheld from a
Participant's Eligible Compensation during each pay period shall be determined
by the Participant's Subscription.

         9.2      Changes in Withholding

         Unless otherwise determined by the Plan Administrator for any future
Offering, a Participant may not elect to increase or decrease the amount to be
withheld from his or her Eligible Compensation for an Offering; provided,
however, that if such elections are permitted for any future Offering, notice of
such elections must be delivered to the Plan Administrator in such form and in
accordance with such terms as the Plan Administrator may establish for the
Offering.

         9.3      Percent Withheld

         The amount of payroll withholding for each Participant for purchases
pursuant to the Plan during any pay period shall be at least 1% but shall not
exceed 15% of the Participant's Eligible Compensation for such pay period, but
in no event shall exceed $15,000 per calendar year. Amounts shall be withheld in
whole percentages only.

         9.4      Payroll Deductions

         Payroll deductions shall commence on the first payday following the
Offering Date and shall continue through the last payday of the Offering unless
sooner altered or terminated as provided in the Plan.

         9.5      Memorandum Accounts

         Individual accounts shall be maintained for each Participant for
memorandum purposes only. All payroll deductions from a Participant's
compensation shall be credited to such account but shall be deposited with the
general funds of the Company. All payroll deductions received or held by the
Company may be used by the Company for any corporate purpose.

         9.6      No Interest

         No interest shall be paid on payroll deductions received or held by the
Company.

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         9.7      Acquisition of Common Stock

         On each Purchase Date of an Offering, each Participant shall
automatically acquire, pursuant to the exercise of the Participant's Option, the
number of shares of Common Stock arrived at by dividing the total amount of the
Participant's accumulated payroll deductions for the Purchase Period by the
Purchase Price; provided, however, that the number of shares of Common Stock
purchased by the Participant shall not exceed the number of whole shares of
Common Stock so determined, unless the Plan Administrator has determined for any
future Offering that fractional shares may be issued under the Plan; and
provided, further, that the number of shares of Common Stock purchased by the
Participant shall not exceed the number of shares for which Options have been
granted to the Participant pursuant to Section 8.1.

         9.8      Refund of Excess Amounts

         Any cash balance remaining in the Participant's account at the
termination of each Purchase Period shall be refunded to the Participant as soon
as practical after the Purchase Date without the payment of any interest;
provided, however, that if the Participant participates in the next Purchase
Period, any cash balance remaining in the Participant's account shall be applied
to the purchase of Common Stock in the new Purchase Period, provided such
purchase complies with Section 8.1.

         9.9      Withholding Obligations

         At the time the Option is exercised, in whole or in part, or at the
time some or all of the Common Stock is disposed of, the Participant shall make
adequate provision for federal and state withholding obligations of the Company,
if any, that arise upon exercise of the Option or upon disposition of the Common
Stock. The Company may withhold from the Participant's compensation the amount
necessary to meet such withholding obligations.

         9.10     Termination of Participation

         No Common Stock shall be purchased on behalf of a Participant on a
Purchase Date if his or her participation in the Offering or the Plan has
terminated on or before such Purchase Date.

         9.11     Procedural Matters

         The Company may, from time to time, establish (a) limitations on the
frequency and/or number of any permitted changes in the amount withheld during
an Offering, as set forth in Section 9.2, (b) an exchange ratio applicable to
amounts withheld in a currency other than U.S. dollars, (c) payroll withholding
in excess of the amount designated by a Participant in order to adjust for
delays or mistakes in the Company's processing of properly completed withholding
elections and (d) such other limitations or procedures as deemed advisable by
the Company in the Company's sole discretion that are consistent with the Plan
and in accordance with the requirements of Code Section 423.

         9.12     Leaves of Absence

         During leaves of absence approved by the Company and meeting the
requirements of the applicable Treasury Regulations promulgated under the Code,
a Participant may elect to continue participation in the Plan by delivering cash
payments to the Plan Administrator on the Participant's normal paydays equal to
the amount of his or her payroll deduction under the Plan had the Participant
not taken a leave of absence. Currently, the Treasury Regulations provide that a
Participant may continue participation in the Plan only during the first 90 days
of a leave of absence unless the Participant's reemployment rights are
guaranteed by statute or contract.

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SECTION 10.  COMMON STOCK PURCHASED UNDER THE PLAN

         10.1     ESPP Broker

         If the Plan Administrator designates or approves a stock brokerage or
other financial services firm (the "ESPP Broker") to hold shares purchased under
the Plan for the accounts of Participants, the following procedures shall apply.
Promptly following each Purchase Date, the number of shares of Common Stock
purchased by each Participant shall be deposited into an account established in
the Participant's name with the ESPP Broker. Each Participant shall be the
beneficial owner of the Common Stock purchased under the Plan and shall have all
rights of beneficial ownership in such Common Stock. A Participant shall be free
to undertake a disposition of the shares of Common Stock in his or her account
at any time, but, in the absence of such a disposition, the shares of Common
Stock must remain in the Participant's account at the ESPP Broker until the
holding period set forth in Code Section 423 has been satisfied. With respect to
shares of Common Stock for which the holding period set forth above has been
satisfied, the Participant may move those shares of Common Stock to another
brokerage account of the Participant's choosing or request that a stock
certificate be issued and delivered to him or her. Dividends paid in the form of
shares of Common Stock with respect to Common Stock in a Participant's account
shall be credited to such account. A Participant who is not subject to payment
of U.S. income taxes may move his or her shares of Common Stock to another
brokerage account of his or her choosing or request that a stock certificate be
delivered to him or her at any time, without regard to the Code Section 423
holding period.

         10.2     Notice of Disposition

         By entering the Plan, each Participant agrees to promptly give the
Company notice of any Common Stock disposed of within the later of one year from
the Purchase Date and two years from the Offering Date for such Common Stock,
showing the number of such shares disposed of and the Purchase Date and Offering
Date for such Common Stock. This notice shall not be required if and so long as
the Company has a designated ESPP Broker.

SECTION 11.  VOLUNTARY WITHDRAWAL

         11.1     Withdrawal From an Offering

         A Participant may withdraw from an Offering by signing and delivering
to the Company's Plan Administrator a written notice of withdrawal on a form
provided by the Company for such purpose. Such withdrawal must be elected at
least 10 days prior to the end of the Purchase Period for which such withdrawal
is to be effective or by any other date specified by the Plan Administrator for
any future Offering. If a Participant withdraws after the Purchase Date for a
Purchase Period of an Offering, the withdrawal shall not affect Common Stock
acquired by the Participant in any earlier Purchase Periods. Unless otherwise
indicated, withdrawal from an Offering shall not result in a withdrawal from the
Plan or any succeeding Offering therein. A Participant is prohibited from again
participating in the same Offering at any time upon withdrawal from such
Offering. The Company may, from time to time, impose a requirement that the
notice of withdrawal be on file with the Plan Administrator for a reasonable
period prior to the effectiveness of the Participant's withdrawal.

         11.2     Withdrawal From the Plan

         A Participant may withdraw from the Plan by signing a written notice of
withdrawal on a form provided by the Company for such purpose and delivering
such notice to the Plan Administrator. Such notice must be delivered at least 10
days prior to the end of the Purchase Period for which such withdrawal is to be
effective or by any other date specified by the Plan Administrator for any
future Offering. In the event a Participant voluntarily elects to withdraw from
the Plan, the Participant may not resume participation in the Plan during the
same Offering, but may participate in any subsequent Offering under the Plan by
again satisfying the definition of Eligible Employee. The Company may impose,
from time to time, a requirement that the notice of

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withdrawal be on file with the Plan Administrator for a reasonable period prior
to the effectiveness of the Participant's withdrawal.

11.3     Return of Payroll Deductions

         Upon withdrawal from an Offering pursuant to Section 11.1 or from the
Plan pursuant to Section 11.2, the withdrawing Participant's accumulated payroll
deductions that have not been applied to the purchase of Common Stock shall be
returned as soon as practical after the withdrawal, without the payment of any
interest, to the Participant and the Participant's interest in the Offering
shall terminate. Such accumulated payroll deductions may not be applied to any
other Offering under the Plan.

SECTION 12.  TERMINATION OF EMPLOYMENT

         Termination of a Participant's employment with the Company or a
Designated Subsidiary for any reason, including retirement, death or any other
failure of a Participant to remain an employee of the Company or a Designated
Subsidiary, shall immediately terminate the Participant's participation in the
Plan. The payroll deductions credited to the Participant's account since the
last Purchase Date shall, as soon as practical, be returned to the Participant
or, in the case of a Participant's death, to the Participant's legal
representative or designated beneficiary as provided in Section 13.2, and all of
the Participant's rights under the Plan shall terminate. Interest shall not be
paid on sums returned to a Participant pursuant to this Section 12.

SECTION 13.  RESTRICTIONS ON ASSIGNMENT

13.1     Transferability

         An Option granted under the Plan shall not be transferable and such
Option shall be exercisable during the Participant's lifetime only by the
Participant. The Company will not recognize, and shall be under no duty to
recognize, any assignment or purported assignment by a Participant of the
Participant's interest in the Plan, of his or her Option or of any rights under
his or her Option.

13.2     Beneficiary Designation

         The Plan Administrator may permit a Participant to designate a
beneficiary who is to receive any shares and cash, if any, from the
Participant's account under the Plan in the event the Participant dies after the
Purchase Date for an Offering but prior to delivery to such Participant of such
shares and cash. In addition, the Plan Administrator may permit a Participant to
designate a beneficiary who is to receive any cash from the Participant's
account under the Plan in the event that the Participant dies before the
Purchase Date for an Offering. Such designation may be changed by the
Participant at any time by written notice to the Plan Administrator.

SECTION 14.  NO RIGHTS AS SHAREHOLDER UNTIL SHARES ISSUED

         With respect to shares of Common Stock subject to an Option, a
Participant shall not be deemed to be a shareholder of the Company, and he or
she shall not have any of the rights or privileges of a shareholder. A
Participant shall have the rights and privileges of a shareholder of the Company
when, but not until, a certificate or its equivalent has been issued to the
Participant for the shares following exercise of the Participant's Option.

SECTION 15.  LIMITATIONS ON SALE OF COMMON STOCK PURCHASED UNDER THE PLAN

         The Plan is intended to provide Common Stock for investment and not for
resale. The Company does not, however, intend to restrict or influence any
Participant in the conduct of his or her own affairs. A Participant, therefore,
may sell Common Stock purchased under the Plan at any time he or she chooses,
subject

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to compliance with any applicable federal and state securities laws. A
Participant assumes the risk of any market fluctuations in the price of the
Common Stock.

SECTION 16.  AMENDMENT OF THE PLAN

         The Board may amend the Plan in such respects as it shall deem
advisable; provided, however, that, to the extent required for compliance with
Code Section 423 or any applicable law or regulation, shareholder approval will
be required for any amendment that will (a) increase the total number of shares
as to which Options may be granted under the Plan, (b) modify the class of
employees eligible to receive Options, or (c) otherwise require shareholder
approval under any applicable law or regulation.

SECTION 17.  TERMINATION OF THE PLAN

         The Plan shall have no fixed termination date. Notwithstanding the
foregoing, the Board may suspend or terminate the Plan at any time. During any
period of suspension or upon termination of the Plan, no Options shall be
granted; provided, however, that suspension or termination of the Plan shall
have no effect on Options granted prior thereto.

SECTION 18.  NO RIGHTS AS AN EMPLOYEE

         Nothing in the Plan shall be construed to give any person (including
any Eligible Employee or Participant) the right to remain in the employ of the
Company or a Parent or Subsidiary Corporation or to affect the right of the
Company or a Parent or Subsidiary Corporation to terminate the employment of any
person (including any Eligible Employee or Participant) at any time with or
without cause.

SECTION 19.  EFFECT UPON OTHER PLANS

         The adoption of the Plan shall not affect any other compensation or
incentive plans in effect for the Company or any Parent or Subsidiary
Corporation. Nothing in this Plan shall be construed to limit the right of the
Company, any Parent Corporation or Subsidiary Corporation to (a) establish any
other forms of incentives or compensation for employees of the Company, a Parent
Corporation or Subsidiary Corporation or (b) grant or assume options otherwise
than under this Plan in connection with any proper corporate purpose, including,
but not by way of limitation, the grant or assumption of options in connection
with the acquisition, by purchase, lease, merger, consolidation or otherwise, of
the business, stock or assets of any corporation, firm or association.

SECTION 20.  ADJUSTMENTS

         20.1     Adjustment of Shares

         In the event that, at any time or from time to time, a stock dividend,
stock split (but not including the stock dividend approved by the Board on
February 23, 1999), spin-off, combination or exchange of shares,
recapitalization, merger, consolidation, distribution to shareholders other than
a normal cash dividend, or other change in the Company's corporate or capital
structure results in (a) the outstanding shares, or any securities exchanged
therefor or received in their place, being exchanged for a different number or
kind of securities of the Company or of any other corporation or (b) new,
different or additional securities of the Company or of any other corporation
being received by the holders of shares of Common Stock, then (subject to any
required action by the Company's shareholders), the Board or the Committee, in
its sole discretion, shall make such equitable adjustments as it shall deem
appropriate in the circumstances in (i) the maximum number and kind of shares of
Common Stock subject to the Plan as set forth in Section 4 and (ii) the number
and kind of securities that are subject to any outstanding Option and the per
share price of such securities. The determination by the Board or the Committee
as to the terms of any of the foregoing adjustments shall be conclusive and
binding. Notwithstanding the foregoing, a dissolution, liquidation, merger or
asset sale of the Company shall not be governed by this Section 20.1 but shall
be governed by Sections 20.2 and 20.3, respectively.

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         20.2 Merger or Asset Sale of the Company

         In the event of a proposed sale of all or substantially all of the
assets of the Company, or the merger of the Company with or into another
corporation, each outstanding Option shall be assumed or an equivalent option
substituted by the successor corporation or a parent or subsidiary corporation
of the successor corporation. In the event that the successor corporation
refuses to assume or substitute for the Option, the Offering then in progress
shall be shortened by setting a new Purchase Date. The new Purchase Date shall
be a specified date before the date of the Company's proposed sale or merger.
The Board shall notify each Participant in writing, at least 10 business days
prior to the new Purchase Date, that the Purchase Date for the Participant's
Option has been changed to the new Purchase Date and that the Participant's
Option shall be exercised automatically on the new Purchase Date, unless prior
to such date the Participant has withdrawn from the Offering or the Plan as
provided in Section 11 hereof.

         20.3     Dissolution or Liquidation of the Company

         In the event of the proposed dissolution or liquidation of the Company,
the Offering then in progress shall be shortened by setting a new Purchase Date
and shall terminate immediately prior to the consummation of such proposed
dissolution or liquidation, unless provided otherwise by the Board. The new
Purchase Date shall be a specified date before the date of the Company's
proposed dissolution or liquidation. The Board shall notify each Participant in
writing, at least 10 business days prior to the new Purchase Date, that the
Purchase Date for the Participant's Option has been changed to the new Purchase
Date and that the Participant's Option shall be exercised automatically on the
new Purchase Date, unless prior to such date the Participant has withdrawn from
the Offering or the Plan as provided in Section 11 hereof.

         20.4     Limitations

         The grant of Options will in no way affect the Company's right to
adjust, reclassify, reorganize or otherwise change its capital or business
structure or to merge, consolidate, dissolve, liquidate or sell or transfer all
or any part of its business or assets.

SECTION 21.  REGISTRATION; CERTIFICATES FOR SHARES

         The Company shall be under no obligation to any Participant to register
for offering or resale under the Securities Act of 1933, as amended, or register
or qualify under state securities laws, any shares of Common Stock. The Company
may issue certificates for shares with such legends and subject to such
restrictions on transfer and stop-transfer instructions as counsel for the
Company deems necessary or desirable for compliance by the Company with federal
and state securities laws.

  SECTION 22.  EFFECTIVE DATE

         The Plan's effective date is the date on which it is approved by the
Company's shareholders, which was April 29, 1999. The Plan was amended and
restated by the Board on April 25, 2000.