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                                                                    EXHIBIT 4.1

                               SUPERGEN, INC.
                           1993 STOCK OPTION PLAN

                    (AS AMENDED THROUGH JULY 11, 2000)

         1. PURPOSES OF THE PLAN. The purposes of this 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. Stock Purchase Rights may also be granted under the Plan.

         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 or Stock Purchase Rights
are, or will be, granted under the Plan.

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

              (d) "CHANGE IN CONTROL" means the occurrence of any of the
following events:

                   (i)    Any "person" (as such term is used in Sections
13(d) and 14(d) of the Exchange Act) becomes the "beneficial owner" (as
defined in Rule 13d-3 of the Exchange Act), directly or indirectly, of
securities of the Company representing fifty percent (50%) or more of the
total voting power represented by the Company's then outstanding voting
securities; or

                   (ii)   The consummation of the sale or disposition by the
Company of all or substantially all of the Company's assets; or

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                   (iii)  The consummation of a merger or consolidation of
the Company with any other corporation, other than a merger or consolidation
which would result in the voting securities of the Company outstanding
immediately prior thereto continuing to represent (either by remaining
outstanding or by being converted into voting securities of the surviving
entity or its parent) at least fifty percent (50%) of the total voting power
represented by the voting securities of the Company or such surviving entity
or its parent outstanding immediately after such merger or consolidation.

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

              (f) "COMMITTEE" means a Committee appointed by the Board in
accordance with Section 4 of the Plan.

              (g) "COMMON STOCK" means the Common Stock of the Company.

              (h) "COMPANY" means SuperGen, Inc., a Delaware corporation.

              (i) "CONSULTANT" means any person, including an advisor,
engaged by the Company or a Parent or Subsidiary to render services and who
is compensated for such services.

              (j) "CONTINUOUS STATUS AS A DIRECTOR OR CONSULTANT" means that
the employment relationship, directorship or consulting relationship with the
Company, any Parent, or Subsidiary, is not interrupted or terminated.
Continuous Status as a Director or Consultant shall not be considered
interrupted 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. A leave of absence approved by
the Company shall include sick leave, military leave, or any other personal
leave approved by an authorized representative of the Company. For purposes
of Incentive Stock Options, no such leave may exceed ninety 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, on the 181st 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.

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

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

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

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

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              (o) "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 for the last market trading day prior to the time 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 last market trading day
prior to the day of determination, as reported in The Wall Street Journal or
such other source as the Administrator deems reliable;

                   (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.

              (p) "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.

              (q) "NONSTATUTORY STOCK OPTION" means an Option not intended to
qualify as an Incentive Stock Option.

              (r) "NOTICE OF GRANT" means a written notice evidencing certain
terms and conditions of an individual Option or Stock Purchase Right grant.
The Notice of Grant is part of the Option Agreement.

              (s) "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.

              (t) "OPTION" means a stock option granted pursuant to the Plan.

              (u) "OPTION AGREEMENT" means a written 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.

              (v) "OPTION EXCHANGE PROGRAM" means a program whereby
outstanding options are surrendered in exchange for options with a lower
exercise price.

              (w) "OPTIONED STOCK" means the Common Stock subject to an
Option or Stock Purchase Right.

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              (x) "OPTIONEE" means an Employee, Director or Consultant who
holds an outstanding Option or Stock Purchase Right.

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

              (z) "PLAN" means this SuperGen, Inc. 1993 Stock Plan.

              (aa) "RESTRICTED STOCK" means shares of Common Stock acquired
pursuant to a grant of Stock Purchase Rights under Section 11 below.

              (bb) "RESTRICTED STOCK PURCHASE AGREEMENT" means a written
agreement between the Company and the Optionee evidencing the terms and
restrictions applying to stock purchased under a Stock Purchase Right. The
Restricted Stock Purchase Agreement is subject to the terms and conditions of
the Plan and the Notice of Grant.

              (cc) "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.

              (dd) "SECTION 16(b)" means Section 16(b) of the Securities
Exchange Act of 1934, as amended.

              (ee) "SHARE" means a share of the Common Stock, as adjusted in
accordance with Section 13 of the Plan.

              (ff) "STOCK PURCHASE RIGHT" means the right to purchase Common
Stock pursuant to Section 11 of the Plan, as evidenced by a Notice of Grant.

              (gg) "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
13 of the Plan, the maximum aggregate number of Shares which may be optioned
and sold under the Plan is 5,850,000 Shares. The Shares may be authorized,
but unissued, or reacquired Common Stock.

              If an Option or Stock Purchase Right expires or becomes
unexercisable without having been exercised in full, or is surrendered pursuant
to an Option Exchange Program, 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, whether upon exercise of an Option or Right, shall not be
returned to the Plan and shall not become available for future distribution
under the Plan, except that if Shares of Restricted Stock are repurchased by the
Company at their original purchase price, such Shares shall become available for
future grant under the Plan. For purposes of the preceding sentence, voting
rights shall not be considered a benefit of Share ownership.

                                     -4-

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         4. ADMINISTRATION OF THE PLAN.

               (a) PROCEDURE.

                   (i)    MULTIPLE ADMINISTRATIVE BODIES. The Plan may be
administered by different Committees with respect to different groups of
Service Providers.

                   (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 of the Common
Stock, in accordance with Section 2(n) of the Plan;

                   (ii)   to select the Employees, Directors and Consultants
to whom Options and Stock Purchase Rights may be granted hereunder;

                   (iii)  to determine whether and to what extent Options and
Stock Purchase Rights or any combination thereof, are granted hereunder;

                   (iv)   to determine the number of shares of Common Stock
to be covered by each Option and Stock Purchase Right granted hereunder;

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

                   (vi)   to determine the terms and conditions, not
inconsistent with the terms of the Plan, of any award granted hereunder. Such
terms and conditions include, but are not limited to, the exercise price, the
time or times when Options or Stock Purchase Rights 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 Stock Purchase Right or the shares of Common Stock relating
thereto, based in each case on such factors as the Administrator, in its sole
discretion, shall determine;

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                   (vii)  to reduce the exercise price of any Option or Stock
Purchase Right to the then current Fair Market Value if the Fair Market Value
of the Common Stock covered by such Option or Stock Purchase Right shall have
declined since the date the Option or Stock Purchase Right was granted;

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

                   (ix)   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;

                   (x)    to modify or amend each Option or Stock Purchase
Right (subject to Section 15(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;

                   (xi)   to authorize any person to execute on behalf of the
Company any instrument required to effect the grant of an Option or Stock
Purchase Right previously granted by the Administrator;

                   (xii)  to institute an Option Exchange Program;

                   (xiii) to allow Optionees to satisfy withholding tax
obligations by electing to have the Company withhold from the Shares to be
issued upon exercise of an Option or Stock Purchase Right that number of
Shares having a Fair Market Value equal to the amount required to be
withheld. The Fair Market Value of the Shares to be withheld shall be
determined on the date that the amount of tax to be withheld is to be
determined. All elections by an Optionee to have Shares withheld for this
purpose shall be made in such form and under such conditions as the
Administrator may deem necessary or advisable;

                   (xiv)  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 or Stock Purchase Rights.

         5. ELIGIBILITY. Nonstatutory Stock Options and Stock Purchase Rights
may be granted to Employees, Directors and Consultants. Incentive Stock
Options may be granted only to Employees.

         6. LIMITATIONS.

              (a) Each Option shall be designated in the written 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

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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 deter-mined as of the time the Option
with respect to such Shares is granted.

              (b) Neither the Plan nor any Option or Stock Purchase Right
shall confer upon an Optionee any right with respect to continuing the
Optionee's employment relationship, directorship or consulting relationship
with the Company, nor shall they interfere in any way with the Optionee's
right or the Company's right to terminate such employment relationship,
directorship or consulting relationship at any time, with or without cause.

              (c) The following limitations shall apply to grants of Options
and Stock Purchase Rights to Employees, Directors and Consultants:

                   (i)    No Employee, Director or Consultant shall be
granted, in any fiscal year of the Company, Options and Stock Purchase Rights
to purchase more than 500,000 Shares.

                   (ii)   In connection with his or her initial service with
the Company, an Employee, Director or Consultant may be granted Options and
Stock Purchase Rights to purchase up to an additional 200,000 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 13.

                   (iv)   If an Option or Stock Purchase Right 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 13), the cancelled Option
or Stock Purchase Right will be counted against the limits set forth in
subsections (i) and (ii) above. For this purpose, if the exercise price of an
Option or Stock Purchase Right is reduced, the transaction will be treated as
a cancellation of the Option or Stock Purchase Right and the grant of a new
Option or Stock Purchase Right.

         7. TERM OF PLAN. Subject to Section 19 of the Plan, the Plan shall
become effective upon the earlier to occur of its adoption by the Board or
its approval by the shareholders of the Company as described in Section 19 of
the Plan. It shall continue in effect for a term of ten (10) years unless
terminated earlier under Section 15 of the Plan.

         8. TERM OF OPTION. The term of each Option shall be stated in the
Notice of Grant; provided, however, that 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 Notice of Grant. 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 voting power of all classes of stock of the Company or
any Parent or Subsidiary, the term of the Incentive Stock Option

                                     -7-
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shall be five (5) years from the date of grant or such shorter term as may be
provided in the Notice of Grant.

         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.

                   (ii)   In the case of a Nonstatutory Stock Option, the per
Share exercise price shall be determined by the Administrator. In the case of
a Nonstatutory Stock Option intended to qualify as "performance-based
compensation" within the meaning of Section 162(m) of the Code, the per Share
exercise price shall be no less than 100% of the Fair Market Value per Share
on the date of grant.

                   (iii)  Notwithstanding the foregoing, Options may be
granted with a per Share exercise price of less than 100% of the Fair Market
Value per Share on the date of grant pursuant to a merger or other corporate
transaction.

              (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 which must be satisfied
before the Option may be exercised. In so doing, the Administrator may
specify that an Option may not be exercised until the completion of a service
period.

              (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)    delivery of a properly executed exercise notice
together with such other documentation as the Administrator and the broker,
if applicable, shall require to effect an exercise of the Option and delivery
to the Company of the sale or loan proceeds required to pay the exercise
price;

                   (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 SHAREHOLDER. 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 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 stock certificate evidencing such Shares is 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 shareholder shall exist with respect to
the Optioned Stock, notwithstanding the exercise of the Option. The Company
shall issue (or cause to be issued) such stock certificate 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 stock certificate is
issued, except as provided in Section 13 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.

                                     -9-

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              (b) TERMINATION OF EMPLOYMENT, CONSULTING RELATIONSHIP OR
DIRECTORSHIP. Upon termination of an Optionee's Continuous Status as an
Employee, Director or Consultant, other than upon the Optionee's death or
Disability, the Optionee may exercise his or her Option, but only within such
period of time as is specified in the Notice of Grant, and only to the extent
that the Optionee was entitled to exercise it at the date of termination (but
in no event later than the expiration of the term of such Option as set forth
in the Notice of Grant). In the absence of a specified time in the Notice of
Grant, the Option shall remain exercisable for three (3) months following the
Optionee's termination. In the case of an Incentive Stock Option, such period
of time for exercise shall not exceed three (3) months from the date of
termination. If, on the date of termination, the Optionee is not entitled to
exercise the Optionee's entire Option, the Shares covered by the
unexercisable 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.

              Notwithstanding the above, in the event of an Optionee's change
in status from Consultant or Director to Employee or Employee or Director to
Consultant, an Optionee's Continuous Status as a Director or Consultant shall
not automatically terminate solely as a result of such change in status.
However, in such event, an 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 three months and one day following
such change of status from an Employee to a Consultant.

              (c) DISABILITY OF OPTIONEE. In the event that an Optionee's
Continuous Status as an Employee, Director or Consultant terminates as a
result of the Optionee's Disability, the Optionee may exercise his or her
Option at any time within twelve (12) months from the date of such
termination, but only to the extent that the Optionee was entitled to
exercise it at the date of such termination (but in no event later than the
expiration of the term of such Option as set forth in the Notice of Grant).
If, at the date of termination, the Optionee is not entitled to exercise his
or her entire Option, the Shares covered by the unexercisable 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. In the event of the death of an
Optionee, the Option may be exercised at any time within twelve (12) months
following the date of death (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 acquired the right to exercise the Option by
bequest or inheritance, but only to the extent that the Optionee was entitled
to exercise the Option at the date of death. If, at the time of death, the
Optionee was not entitled to exercise his or her entire Option, the Shares
covered by the unexercisable portion of the Option shall immediately revert
to the Plan. If, after death, the Optionee's estate or a person who acquired
the right to exercise the Option by bequest or inheritance does not exercise
the Option within the time specified herein, the Option shall terminate, and
the Shares covered by such Option shall revert to the Plan.

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              (e) BUYOUT PROVISIONS. The Administrator may at any time offer
to buy out for a payment in cash or Shares, an Option previously granted
based on such terms and conditions as the Administrator shall establish and
communicate to the Optionee at the time that such offer is made.

         11. STOCK PURCHASE RIGHTS.

              (a) RIGHTS TO PURCHASE. Stock Purchase Rights may be issued
either alone, in addition to, or in tandem with other awards granted under
the Plan and/or cash awards made outside of the Plan. After the Administrator
determines that it will offer Stock Purchase Rights under the Plan, it shall
advise the offeree in writing, by means of a Notice of Grant, of the terms,
conditions and restrictions related to the offer, including the number of
Shares that the offeree shall be entitled to purchase, the price to be paid,
and the time within which the offeree must accept such offer, which shall in
no event exceed six (6) months from the date upon which the Administrator
made the determination to grant the Stock Purchase Right. The offer shall be
accepted by execution of a Restricted Stock Purchase Agreement in the form
determined by the Administrator.

              (b) REPURCHASE OPTION. Unless the Administrator deter-mines
other-wise, the Restricted Stock Purchase Agreement shall grant the Company a
repurchase option exercisable upon the voluntary or involuntary termination
of the purchaser's employment with the Company for any reason (including
death or Disability). The purchase price for Shares repurchased pursuant to
the Restricted Stock purchase agreement shall be the original price paid by
the purchaser and may be paid by cancellation of any indebtedness of the
purchaser to the Company. The repurchase option shall lapse at a rate
determined by the Administrator.

              (c) OTHER PROVISIONS. The Restricted Stock Purchase Agreement
shall contain such other terms, provisions and conditions not inconsistent
with the Plan as may be determined by the Administrator in its sole
discretion. In addition, the provisions of Restricted Stock Purchase
Agreements need not be the same with respect to each purchaser.

              (d) RIGHTS AS A SHAREHOLDER. Once the Stock Purchase Right is
exercised, the purchaser shall have the rights equivalent to those of a
shareholder, and shall be a shareholder when his or her purchase is entered
upon the records of the duly authorized transfer agent of the Company. No
adjustment will be made for a dividend or other right for which the record
date is prior to the date the Stock Purchase Right is exercised, except as
provided in Section 13 of the Plan.

         12. NON-TRANSFERABILITY OF OPTIONS AND STOCK PURCHASE RIGHTS. Unless
determined otherwise by the Administrator, an Option or Stock Purchase Right
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 or Stock Purchase Right
transferable, such Option or Stock Purchase Right shall contain such
additional terms and conditions as the Administrator deems appropriate.

         13. ADJUSTMENTS UPON CHANGES IN CAPITALIZATION, DISSOLUTION, MERGER
OR CHANGE IN CONTROL.

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              (a) CHANGES IN CAPITALIZATION. Subject to any required action
by the shareholders of the Company, the number of shares of Common Stock
covered by each outstanding Option and Stock Purchase Right, and the number
of shares of Common Stock which have been authorized for issuance under the
Plan but as to which no Options or Stock Purchase Rights have yet been
granted or which have been returned to the Plan upon cancellation or
expiration of an Option or Stock Purchase Right, as well as the price per
share of Common Stock covered by each such outstanding Option or Stock
Purchase Right, 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 or Stock Purchase Right.

              (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 ten (10) 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 CHANGE IN CONTROL. In the event of a merger of
the Company with or into another corporation, or a Change in Control, each
outstanding Option and Stock Purchase Right shall be assumed or an equivalent
option or right 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 or Stock Purchase
Right, the Optionee shall have the right to exercise the Option or Stock
Purchase Right as to all of the Optioned Stock, including Shares as to which
it would not otherwise be exercisable. If an Option or Stock Purchase Right
is exercisable in lieu of assumption or substitution, the Administrator shall
notify the Optionee that the Option or Stock Purchase Right shall be fully
exercisable for a period of fifteen (15) days from the date of such notice,
and the Option or Stock Purchase Right shall terminate upon the expiration of
such period. For the purposes of this paragraph, the Option or Stock Purchase
Right shall be considered assumed if, following the merger or Change in
Control, the option or right confers the right to purchase or receive, for
each Share of Optioned Stock subject to the Option or Stock Purchase Right
immediately prior to the merger or Change in Control, the consideration
(whether stock, cash, or other securities

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<PAGE>

or property) received in the merger or Change in Control 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 Change in
Control 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
or Stock Purchase Right, for each Share of Optioned Stock subject to the
Option or Stock Purchase Right, 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 Change in
Control.

              (d) ACCELERATION IN THE EVENT OF A CHANGE IN CONTROL. In the
event of a Change in Control the vesting of all Options and Stock Purchase
Rights shall accelerate fully and the Optionee shall have the right to
exercise the Option or Stock Purchase Right as to all of the Optioned Stock,
including Shares as to which it would not otherwise be exercisable.

         14. DATE OF GRANT. The date of grant of an Option or Stock Purchase
Right shall be, for all purposes, the date on which the Administrator makes
the determination granting such Option or Stock Purchase Right, 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.

         15. AMENDMENT AND TERMINATION OF THE PLAN.

              (a) AMENDMENT AND TERMINATION. The Board may at any time amend,
alter, suspend or terminate the Plan.

              (b) SHAREHOLDER APPROVAL. The Company shall obtain shareholder
approval of any Plan amendment to the extent necessary and desirable to
comply with Sections 162(m) or 422 of the Code (or any successor rule or
statute or other applicable law, rule or regulation, including the
requirements of any exchange or quotation system on which the Common Stock is
listed or quoted). Such shareholder approval, if required, shall be obtained
in such a manner and to such a degree as is required by the applicable law,
rule or regulation.

              (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.

         16. CONDITIONS UPON ISSUANCE OF SHARES.

              (a) LEGAL COMPLIANCE. Shares shall not be issued pursuant to
the exercise of an Option or Stock Purchase Right unless the exercise of such
Option or Stock Purchase Right and the issuance and delivery of such Shares
shall comply with all relevant provisions of law, including,

                                     -13-

<PAGE>

without limitation, the Securities Act of 1933, as amended, the Exchange
Act, the rules and regulations promulgated thereunder, Applicable Laws, and
the requirements of any stock exchange or quotation system upon which the
Shares may then be listed or quoted, 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 or Stock Purchase Right, the Company may require the person
exercising such Option or Stock Purchase Right 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.

         17. LIABILITY OF COMPANY.

              (a) 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.

              (b) GRANTS EXCEEDING ALLOTTED SHARES. If the Optioned Stock
covered by an Option or Stock Purchase Right exceeds, as of the date of
grant, the number of Shares which may be issued under the Plan without
additional shareholder approval, such Option or Stock Purchase Right shall be
void with respect to such excess Optioned Stock, unless shareholder approval
of an amendment sufficiently increasing the number of Shares subject to the
Plan is timely obtained in accordance with Section 15(b) of the Plan.

         18. 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.

         19. SHAREHOLDER APPROVAL. Continuance of the Plan shall be subject
to approval by the shareholders of the Company within twelve (12) months
before or after the date the Plan is adopted. Such shareholder approval shall
be obtained in the manner and to the degree required under applicable federal
and state law.

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