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                                                                   EXHIBIT 10.20

                               VISX, INCORPORATED

                                 2000 STOCK PLAN


        1. Purposes of the Plan. The purposes of this 2000 Stock Plan are:

        -      to attract and retain the best available personnel for positions
               of substantial responsibility,

        -      to provide additional incentive to Employees, Directors and
               Consultants, and

        -      to promote the success of the Company's business.

        Options granted under the Plan may be Incentive Stock Options or
Nonstatutory Stock Options, as determined by the Administrator at the time of
grant.

        2. Definitions. As used herein, the following definitions shall apply:

            (a)"Administrator" means the Board or any of its Committees as shall
be administering the Plan, in accordance with Section 4 of the Plan.

            (b) "Applicable Laws" means the requirements relating to the
administration of stock option plans under U. S. state corporate laws, U.S.
federal and state securities laws, the Code, any stock exchange or quotation
system on which the Common Stock is listed or quoted and the applicable laws of
any foreign country or jurisdiction where Options are, or will be, granted under
the Plan.

            (c) "Board" means the Board of Directors of the Company.

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

            (e) "Committee" means a committee of Directors appointed by the
Board in accordance with Section 4 of the Plan.

            (f) "Common Stock" means the common stock of the Company.

            (g) "Company" means VISX, Incorporated, a Delaware corporation.

            (h) "Consultant" means any person, including an advisor, engaged by
the Company or a Parent or Subsidiary to render services to such entity.

            (i) "Director" means a member of the Board.

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            (j) "Disability" means total and permanent disability as defined in
Section 22(e)(3) of the Code.

            (k) "Employee" means any person, including Officers and Directors,
employed by the Company or any Parent or Subsidiary of the Company. A Service
Provider shall not cease to be an Employee in the case of (i) any leave of
absence approved by the Company or (ii) transfers between locations of the
Company or between the Company, its Parent, any Subsidiary, or any successor.
For purposes of Incentive Stock Options, no such leave may exceed ninety (90)
days, unless reemployment upon expiration of such leave is guaranteed by statute
or contract. If reemployment upon expiration of a leave of absence approved by
the Company is not so guaranteed, then three (3) months following the
ninety-first (91st) day of such leave, any Incentive Stock Option held by the
Optionee shall cease to be treated as an Incentive Stock Option and shall be
treated for tax purposes as a Nonstatutory Stock Option. Neither service as a
Director nor payment of a director's fee by the Company shall be sufficient to
constitute "employment" by the Company.

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

            (m) "Fair Market Value" means, as of any date, the value of Common
Stock determined as follows:

                (i) If the Common Stock is listed on any established stock
exchange or a national market system, including without limitation the Nasdaq
National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its
Fair Market Value shall be the closing sales price for such stock (or the
closing bid, if no sales were reported) as quoted on such exchange or system on
the day of determination, as reported in The Wall Street Journal or such other
source as the Administrator deems reliable;

                (ii) If the Common Stock is regularly quoted by a recognized
securities dealer but selling prices are not reported, the Fair Market Value of
a Share of Common Stock shall be the mean between the high bid and low asked
prices for the Common Stock on the day of determination, as reported in The Wall
Street Journal or such other source as the Administrator deems reliable; or

                (iii) In the absence of an established market for the Common
Stock, the Fair Market Value shall be determined in good faith by the
Administrator.

            (n) "Incentive Stock Option" means an Option intended to qualify as
an incentive stock option within the meaning of Section 422 of the Code and the
regulations promulgated thereunder.

            (o) "Nonstatutory Stock Option" means an Option not intended to
qualify as an Incentive Stock Option.

            (p) "Notice of Grant" means a written or electronic notice
evidencing certain terms and conditions of an individual Option grant. The
Notice of Grant is part of the Option Agreement.


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            (q) "Officer" means a person who is an officer of the Company within
the meaning of Section 16 of the Exchange Act and the rules and regulations
promulgated thereunder.

            (r) "Option" means a stock option granted pursuant to the Plan.

            (s) "Option Agreement" means an agreement between the Company and an
Optionee evidencing the terms and conditions of an individual Option grant. The
Option Agreement is subject to the terms and conditions of the Plan.

            (t) "Optioned Stock" means the Common Stock subject to an Option.

            (u) "Optionee" means the holder of an outstanding Option granted
under the Plan.

            (v) "Parent" means a "parent corporation," whether now or hereafter
existing, as defined in Section 424(e) of the Code.

            (w) "Plan" means this 2000 Stock Plan.

            (x) "Rule 16b-3" means Rule 16b-3 of the Exchange Act or any
successor to Rule 16b-3, as in effect when discretion is being exercised with
respect to the Plan.

            (y) "Section 16(b)" means Section 16(b) of the Exchange Act.

            (z) "Service Provider" means an Employee, Director or Consultant.

            (aa) "Share" means a share of the Common Stock, as adjusted in
accordance with Section 12 of the Plan.

            (bb) "Subsidiary" means a "subsidiary corporation", whether now or
hereafter existing, as defined in Section 424(f) of the Code.

        3. Stock Subject to the Plan. Subject to the provisions of Section 12 of
the Plan, the maximum aggregate number of Shares that may be optioned and sold
under the Plan is 3,000,000 Shares. The Shares may be authorized, but unissued,
or reacquired Common Stock.

        If an Option expires or becomes unexercisable without having been
exercised in full, the unpurchased Shares which were subject thereto shall
become available for future grant or sale under the Plan (unless the Plan has
terminated); provided, however, that Shares that have actually been issued under
the Plan, upon exercise of an Option, shall not be returned to the Plan and
shall not become available for future distribution under the Plan.

        4. Administration of the Plan.

            (a) Procedure.

                (i) Multiple Administrative Bodies. Different Committees may
administer the Plan with respect to different groups of Service Providers.


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                (ii) Section 162(m). To the extent that the Administrator
determines it to be desirable to qualify Options granted hereunder as
"performance-based compensation" within the meaning of Section 162(m) of the
Code, the Plan shall be administered by a Committee of two or more "outside
directors" within the meaning of Section 162(m) of the Code.

                (iii) Rule 16b-3. To the extent desirable to qualify
transactions hereunder as exempt under Rule 16b-3, the transactions contemplated
hereunder shall be structured to satisfy the requirements for exemption under
Rule 16b-3.

                (iv) Other Administration. Other than as provided above, the
Plan shall be administered by (A) the Board or (B) a Committee, which committee
shall be constituted to satisfy Applicable Laws.

            (b) Powers of the Administrator. Subject to the provisions of the
Plan, and in the case of a Committee, subject to the specific duties delegated
by the Board to such Committee, the Administrator shall have the authority, in
its discretion:

                (i) to determine the Fair Market Value in accordance with
Section 2(m) of the Plan;

                (ii) to select the Service Providers to whom Options may be
granted hereunder;

                (iii) to determine the number of shares of Common Stock to be
covered by each Option granted hereunder;

                (iv) to approve forms of agreement for use under the Plan;

                (v) to determine the terms and conditions, not inconsistent with
the terms of the Plan, of any Option granted hereunder. Such terms and
conditions include, but are not limited to, the exercise price in accordance
with Section 9(a), the time or times when Options may be exercised (which may be
based on performance criteria), any vesting acceleration or waiver of forfeiture
restrictions, and any restriction or limitation regarding any Option or the
shares of Common Stock relating thereto, based in each case on such factors as
the Administrator, in its sole discretion, shall determine;

                (vi) to construe and interpret the terms of the Plan and awards
granted pursuant to the Plan;

                (vii) to prescribe, amend and rescind rules and regulations
relating to the Plan, including rules and regulations relating to sub-plans
established for the purpose of qualifying for preferred tax treatment under
foreign tax laws;

                (viii) to modify or amend each Option (subject to Section 14(c)
of the Plan), including the discretionary authority to extend the
post-termination exercisability period of Options longer than is otherwise
provided for in the Plan, provided that the Board may not amend any Option



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to reduce the exercise price of the option below 100% of the Fair Market Value
per Share on the date of grant;

                (ix) to authorize any person to execute on behalf of the Company
any instrument required to effect the grant of an Option previously granted by
the Administrator;

                (x) to make all other determinations deemed necessary or
advisable for administering the Plan.

            (c) Effect of Administrator's Decision. The Administrator's
decisions, determinations and interpretations shall be final and binding on all
Optionees and any other holders of Options.

        5. Eligibility. Nonstatutory Stock Options may be granted to Service
Providers. Incentive Stock Options may be granted only to Employees.

        6. Limitations.

            (a) Each Option shall be designated in the Option Agreement as
either an Incentive Stock Option or a Nonstatutory Stock Option. However,
notwithstanding such designation, to the extent that the aggregate Fair Market
Value of the Shares with respect to which Incentive Stock Options are
exercisable for the first time by the Optionee during any calendar year (under
all plans of the Company and any Parent or Subsidiary) exceeds $100,000, such
Options shall be treated as Nonstatutory Stock Options. For purposes of this
Section 6(a), Incentive Stock Options shall be taken into account in the order
in which they were granted. The Fair Market Value of the Shares shall be
determined as of the time the Option with respect to such Shares is granted.

            (b) Neither the Plan nor any Option shall confer upon an Optionee
any right with respect to continuing the Optionee's relationship as a Service
Provider with the Company, nor shall they interfere in any way with the
Optionee's right or the Company's right to terminate such relationship at any
time, with or without cause.

            (c) The following limitations shall apply to grants of Options:

                (i) No Service Provider shall be granted, in any fiscal year of
the Company, Options to purchase more than 500,000 Shares.

                (ii) In connection with his or her initial service, a Service
Provider may be granted Options to purchase up to an additional 500,000 Shares,
which shall not count against the limit set forth in subsection (i) above.

                (iii) The foregoing limitations shall be adjusted
proportionately in connection with any change in the Company's capitalization as
described in Section 12.

                (iv) If an Option is cancelled in the same fiscal year of the
Company in which it was granted (other than in connection with a transaction
described in Section 12), the cancelled Option will be counted against the
limits set forth in subsections (i) and (ii) above. For


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this purpose, if the exercise price of an Option is reduced, the transaction
will be treated as a cancellation of the Option and the grant of a new Option.

        7. Term of Plan. Subject to Section 18 of the Plan, the Plan shall
become effective upon its adoption by the Board. It shall continue in effect for
a term of ten (10) years unless terminated earlier under Section 14 of the Plan.

        8. Term of Option. The term of each Option shall be stated in the Option
Agreement. In the case of an Incentive Stock Option, the term shall be ten (10)
years from the date of grant or such shorter term as may be provided in the
Option Agreement. Moreover, in the case of an Incentive Stock Option granted to
an Optionee who, at the time the Incentive Stock Option is granted, owns stock
representing more than ten percent (10%) of the total combined voting power of
all classes of stock of the Company or any Parent or Subsidiary, the term of the
Incentive Stock Option shall be five (5) years from the date of grant or such
shorter term as may be provided in the Option Agreement.

        9. Option Exercise Price and Consideration.

            (a) Exercise Price. The per share exercise price for the Shares to
be issued pursuant to exercise of an Option shall be determined by the
Administrator, subject to the following:

                (i) In the case of an Incentive Stock Option

                    (A) granted to an Employee who, at the time the Incentive
Stock Option is granted, owns stock representing more than ten percent (10%) of
the voting power of all classes of stock of the Company or any Parent or
Subsidiary, the per Share exercise price shall be no less than 110% of the Fair
Market Value per Share on the date of grant.

                    (B) granted to any Employee other than an Employee described
in paragraph (A) immediately above, the per Share exercise price shall be no
less than 100% of the Fair Market Value per Share on the date of grant.

            (b) Waiting Period and Exercise Dates. At the time an Option is
granted, the Administrator shall fix the period within which the Option may be
exercised and shall determine any conditions that must be satisfied before the
Option may be exercised.

            (c) Form of Consideration. The Administrator shall determine the
acceptable form of consideration for exercising an Option, including the method
of payment. In the case of an Incentive Stock Option, the Administrator shall
determine the acceptable form of consideration at the time of grant. Such
consideration may consist entirely of:

                (i) cash;

                (ii) check;

                (iii) promissory note;


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                (iv) other Shares which (A) in the case of Shares acquired upon
exercise of an option, have been owned by the Optionee for more than six months
on the date of surrender, and (B) have a Fair Market Value on the date of
surrender equal to the aggregate exercise price of the Shares as to which said
Option shall be exercised;

                (v) consideration received by the Company under a cashless
exercise program implemented by the Company in connection with the Plan;

                (vi) a reduction in the amount of any Company liability to the
Optionee, including any liability attributable to the Optionee's participation
in any Company-sponsored deferred compensation program or arrangement;

                (vii) any combination of the foregoing methods of payment; or

                (viii) such other consideration and method of payment for the
issuance of Shares to the extent permitted by Applicable Laws.

        10. Exercise of Option.

            (a) Procedure for Exercise; Rights as a Stockholder. Any Option
granted hereunder shall be exercisable according to the terms of the Plan and at
such times and under such conditions as determined by the Administrator and set
forth in the Option Agreement. An Option may not be exercised for a fraction of
a Share.

            An Option shall be deemed exercised when the Company receives: (i)
written or electronic notice of exercise (in accordance with the Option
Agreement) from the person entitled to exercise the Option, and (ii) full
payment for the Shares with respect to which the Option is exercised. Full
payment may consist of any consideration and method of payment authorized by the
Administrator and permitted by the Option Agreement and the Plan. Shares issued
upon exercise of an Option shall be issued in the name of the Optionee or, if
requested by the Optionee, in the name of the Optionee and his or her spouse.
Until the Shares are issued (as evidenced by the appropriate entry on the books
of the Company or of a duly authorized transfer agent of the Company), no right
to vote or receive dividends or any other rights as a stockholder shall exist
with respect to the Optioned Stock, notwithstanding the exercise of the Option.
The Company shall issue (or cause to be issued) such Shares promptly after the
Option is exercised. No adjustment will be made for a dividend or other right
for which the record date is prior to the date the Shares are issued, except as
provided in Section 12 of the Plan.

            Exercising an Option in any manner shall decrease the number of
Shares thereafter available, both for purposes of the Plan and for sale under
the Option, by the number of Shares as to which the Option is exercised.

            (b) Termination of Relationship as a Service Provider. If an
Optionee ceases to be a Service Provider, other than upon the Optionee's death
or Disability, the Optionee may exercise his or her Option within such period of
time as is specified in the Option Agreement to the extent that the Option is
vested on the date of termination (but in no event later than the expiration of
the term

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of such Option as set forth in the Option Agreement). In the absence of a
specified time in the Option Agreement, the Option shall remain exercisable for
three (3) months following the Optionee's termination. If, on the date of
termination, the Optionee is not vested as to his or her entire Option, the
Shares covered by the unvested portion of the Option shall revert to the Plan.
If, after termination, the Optionee does not exercise his or her Option within
the time specified by the Administrator, the Option shall terminate, and the
Shares covered by such Option shall revert to the Plan.

            (c) Disability of Optionee. If an Optionee ceases to be a Service
Provider as a result of the Optionee's Disability, the Optionee may exercise his
or her Option within such period of time as is specified in the Option Agreement
to the extent the Option is vested on the date of termination (but in no event
later than the expiration of the term of such Option as set forth in the Option
Agreement). In the absence of a specified time in the Option Agreement, the
Option shall remain exercisable for twelve (12) months following the Optionee's
termination. If, on the date of termination, the Optionee is not vested as to
his or her entire Option, the Shares covered by the unvested portion of the
Option shall revert to the Plan. If, after termination, the Optionee does not
exercise his or her Option within the time specified herein, the Option shall
terminate, and the Shares covered by such Option shall revert to the Plan.

            (d) Death of Optionee. If an Optionee dies while a Service Provider,
the Option may be exercised within such period of time as is specified in the
Option Agreement (but in no event later than the expiration of the term of such
Option as set forth in the Notice of Grant), by the Optionee's estate or by a
person who acquires the right to exercise the Option by bequest or inheritance,
but only to the extent that the Option is vested on the date of death. In the
absence of a specified time in the Option Agreement, the Option shall remain
exercisable for twelve (12) months following the Optionee's termination. If, at
the time of death, the Optionee is not vested as to his or her entire Option,
the Shares covered by the unvested portion of the Option shall immediately
revert to the Plan. The Option may be exercised by the executor or administrator
of the Optionee's estate or, if none, by the person(s) entitled to exercise the
Option under the Optionee's will or the laws of descent or distribution. If the
Option is not so exercised within the time specified herein, the Option shall
terminate, and the Shares covered by such Option shall revert to the Plan.

        11. Non-Transferability of Options. Unless determined otherwise by the
Administrator, an Option may not be sold, pledged, assigned, hypothecated,
transferred, or disposed of in any manner other than by will or by the laws of
descent or distribution and may be exercised, during the lifetime of the
Optionee, only by the Optionee. If the Administrator makes an Option
transferable, such Option shall contain such additional terms and conditions as
the Administrator deems appropriate.

        12. Adjustments Upon Changes in Capitalization, Dissolution, Merger or
Asset Sale.

            (a) Changes in Capitalization. Subject to any required action by the
stockholders of the Company, the number of shares of Common Stock covered by
each outstanding Option, and the number of shares of Common Stock which have
been authorized for issuance under the Plan but as to which no Options have yet
been granted or which have been returned to the Plan upon cancellation or
expiration of an Option, as well as the price per share of Common Stock covered
by

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each such outstanding Option, shall be proportionately adjusted for any increase
or decrease in the number of issued shares of Common Stock resulting from a
stock split, reverse stock split, stock dividend, combination or
reclassification of the Common Stock, or any other increase or decrease in the
number of issued shares of Common Stock 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 issuance 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 of Common Stock subject to an Option.

            (b) Dissolution or Liquidation. In the event of the proposed
dissolution or liquidation of the Company, the Administrator shall notify each
Optionee as soon as practicable prior to the effective date of such proposed
transaction. The Administrator in its discretion may provide for an Optionee to
have the right to exercise his or her Option until fifteen (15) days prior to
such transaction as to all of the Optioned Stock covered thereby, including
Shares as to which the Option would not otherwise be exercisable. In addition,
the Administrator may provide that any Company repurchase option applicable to
any Shares purchased upon exercise of an Option shall lapse as to all such
Shares, provided the proposed dissolution or liquidation takes place at the time
and in the manner contemplated. To the extent it has not been previously
exercised, an Option will terminate immediately prior to the consummation of
such proposed action.

            (c) Merger or Asset Sale. In the event of a merger of the Company
with or into another corporation, or the sale of substantially all of the assets
of the Company, each outstanding Option shall be assumed or an equivalent option
substituted by the successor corporation or a Parent or Subsidiary of the
successor corporation. In the event that the successor corporation refuses to
assume or substitute for the Option, the Optionee shall fully vest in and have
the right to exercise the Option as to all of the Optioned Stock, including
Shares as to which it would not otherwise be vested or exercisable. If an Option
becomes fully vested and exercisable in lieu of assumption or substitution in
the event of a merger or sale of assets, the Administrator shall notify the
Optionee in writing or electronically that the Option shall be fully vested and
exercisable for a period of fifteen (15) days from the date of such notice, and
the Option shall terminate upon the expiration of such period. For the purposes
of this paragraph, the Option shall be considered assumed if, following the
merger or sale of assets, the option confers the right to purchase or receive,
for each Share of Optioned Stock subject to the Option immediately prior to the
merger or sale of assets, the consideration (whether stock, cash, or other
securities or property) received in the merger or sale of assets by holders of
Common Stock for each Share held on the effective date of the transaction (and
if holders were offered a choice of consideration, the type of consideration
chosen by the holders of a majority of the outstanding Shares); provided,
however, that if such consideration received in the merger or sale of assets is
not solely common stock of the successor corporation or its Parent, the
Administrator may, with the consent of the successor corporation, provide for
the consideration to be received upon the exercise of the Option, for each Share
of Optioned Stock subject to the Option, to be solely common stock of the
successor corporation or its Parent equal in fair market value to the per share
consideration received by holders of Common Stock in the merger or sale of
assets.


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        13. Date of Grant. The date of grant of an Option shall be, for all
purposes, the date on which the Administrator makes the determination granting
such Option, or such other later date as is determined by the Administrator.
Notice of the determination shall be provided to each Optionee within a
reasonable time after the date of such grant.

        14. Amendment and Termination of the Plan.

            (a) Amendment and Termination. The Board may at any time amend,
alter, suspend or terminate the Plan, provided that the Board may not amend the
Plan to permit the grant of any Option with an exercise price below 100% of the
Fair Market Value of the Shares on the date of grant or to permit the repricing
of any option without stockholder approval.

            (b) Stockholder Approval. The Company shall obtain stockholder
approval of any Plan amendment to the extent necessary and desirable to comply
with Applicable Laws.

            (c) Effect of Amendment or Termination. No amendment, alteration,
suspension or termination of the Plan shall impair the rights of any Optionee,
unless mutually agreed otherwise between the Optionee and the Administrator,
which agreement must be in writing and signed by the Optionee and the Company.
Termination of the Plan shall not affect the Administrator's ability to exercise
the powers granted to it hereunder with respect to Options granted under the
Plan prior to the date of such termination.

        15. Conditions Upon Issuance of Shares.

            (a) Legal Compliance. Shares shall not be issued pursuant to the
exercise of an Option unless the exercise of such Option and the issuance and
delivery of such Shares shall comply with Applicable Laws and shall be further
subject to the approval of counsel for the Company with respect to such
compliance.

            (b) Investment Representations. As a condition to the exercise of an
Option, the Company may require the person exercising such Option to represent
and warrant at the time of any such exercise that the Shares are being purchased
only for investment and without any present intention to sell or distribute such
Shares if, in the opinion of counsel for the Company, such a representation is
required.

        16. Inability to Obtain Authority. The inability of the Company to
obtain authority from any regulatory body having jurisdiction, which authority
is deemed by the Company's counsel to be necessary to the lawful issuance and
sale of any Shares hereunder, shall relieve the Company of any liability in
respect of the failure to issue or sell such Shares as to which such requisite
authority shall not have been obtained.

        17. Reservation of Shares. The Company, during the term of this Plan,
will at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.


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        18. Stockholder Approval. The Plan shall be subject to approval by the
stockholders of the Company within twelve (12) months after the date the Plan is
adopted. Such stockholder approval shall be obtained in the manner and to the
degree required under Applicable Laws.


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