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                                                                     EXHIBIT 4.1


                                     AVIRON

                     1999 NON-OFFICER EQUITY INCENTIVE PLAN

                      ADOPTED EFFECTIVE SEPTEMBER 21, 1999

                 AMENDED BY THE BOARD OF DIRECTORS JULY 26, 2000

                AMENDED BY THE BOARD OF DIRECTORS APRIL 25, 2001

              AMENDED BY THE BOARD OF DIRECTORS SEPTEMBER 24, 2001



1.      PURPOSES.

        (a) The purpose of the Plan is to provide a means by which selected
Employees of and Consultants to the Company and its Affiliates may be given an
opportunity to benefit from increases in value of the stock of the Company
through the granting of (i) nonstatutory Stock Options, (ii) stock bonuses,
(iii) rights to purchase restricted stock, and (iv) stock appreciation rights,
all as defined below. The Plan does not extend eligibility to an Employee
considered to be an Officer of the Company or to a Director of the Company.

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

        (c) The Company intends that the Stock Awards issued under the Plan
shall, in the discretion of the Board or any Committee to which responsibility
for administration of the Plan has been delegated pursuant to subsection 3(c),
be either (i) nonstatutory Stock Options granted pursuant to Section 6 hereof,
(ii) stock bonuses or rights to purchase restricted stock granted pursuant to
Section 7 hereof, or (iii) stock appreciation rights granted pursuant to Section
8 hereof. All Options shall be separately designated in such form as issued
pursuant to Section 6, and a separate certificate or certificates will be issued
for shares purchased on exercise of each type of Option.

2.      DEFINITIONS.

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

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

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

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


                                       1.
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        (e) "COMPANY" means Aviron, a Delaware corporation.

        (f) "CONCURRENT STOCK APPRECIATION RIGHT" or "CONCURRENT RIGHT" means a
right granted pursuant to subsection 8(b)(2) of the Plan.

        (g) "CONSULTANT" means any person, including an advisor, engaged by the
Company or an Affiliate to render consulting services and who is compensated for
such services, provided that the term "Consultant" shall not include Directors
who are paid only a director's fee by the Company or who are not compensated by
the Company for their services as Directors.

        (h) "CONTINUOUS STATUS AS AN EMPLOYEE OR CONSULTANT" means the
employment or relationship as a Consultant is not interrupted or terminated. The
Board, in its sole discretion, may determine whether Continuous Status as an
Employee or Consultant shall be considered interrupted in the case of: (i) any
leave of absence approved by the Board, including sick leave, military leave, or
any other personal leave; or (ii) transfers between locations of the Company or
between the Company, Affiliates or their successors.

        (i) "COVERED EMPLOYEE" means the chief executive officer and the four
(4) other highest compensated officers of the Company for whom total
compensation is required to be reported to shareholders under the Exchange Act,
as determined for purposes of Section 162(m) of the Code.

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

        (k) "EMPLOYEE" means any person, excluding Non-Employee Directors and
Officers, employed by the Company or any Affiliate of 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 the common
stock of the Company determined as follows:

                (1) If the common stock is listed on any established stock
exchange or a national market system, including without limitation the National
Market of The Nasdaq Stock Market, the Fair Market Value of a share of common
stock shall be the closing sales price for such stock (or the closing bid, if no
sales were reported) as quoted on such system or exchange (or the exchange with
the greatest volume of trading in 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 Board deems reliable;

                (2) If the common stock is quoted on The Nasdaq Stock Market
(but not on the National Market thereof) or 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 bid and 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 Board deems reliable;


                                       2.
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                (3) In the absence of an established market for the common
stock, the Fair Market Value shall be determined in good faith by the Board.

        (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) "INDEPENDENT STOCK APPRECIATION RIGHT" or "INDEPENDENT RIGHT" means
a right granted pursuant to subsection 8(b)(3) of the Plan.

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

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

        (r) "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.

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

        (t) "OPTION AGREEMENT" means a written agreement between the Company and
an Optionee evidencing the terms and conditions of an individual Option grant.
Each Option Agreement shall be subject to the terms and conditions of the Plan.

        (u) "OPTIONEE" means a person who holds an outstanding Option.

        (v) "OUTSIDE DIRECTOR" means a Director who either (i) is not a current
employee of the Company or an "affiliated corporation" (within the meaning of
Treasury regulations promulgated under Section 162(m) of the Code), is not a
former employee of the Company or an "affiliated corporation" receiving
compensation for prior services (other than benefits under a tax qualified
pension plan), was not an officer of the Company or an "affiliated corporation"
at any time, and is not currently receiving direct or indirect remuneration from
the Company or an "affiliated corporation" for services in any capacity other
than as a Director, or (ii) is otherwise considered an "outside director" for
purposes of Section 162(m) of the Code.

        (w) "PLAN" means this Aviron 1999 Non-Officer Equity Incentive 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.


                                       3.
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        (y) "STOCK APPRECIATION RIGHT" means any of the various types of rights
which may be granted under Section 8 of the Plan.

        (z) "STOCK AWARD" means any right granted under the Plan, including any
Option, any stock bonus, any right to purchase restricted stock, and any Stock
Appreciation Right.

        (aa) "STOCK AWARD AGREEMENT" means a written agreement between the
Company and a holder of a Stock Award evidencing the terms and conditions of an
individual Stock Award grant. Each Stock Award Agreement shall be subject to the
terms and conditions of the Plan.

        (bb) "TANDEM STOCK APPRECIATION RIGHT" or "TANDEM RIGHT" means a right
granted pursuant to subsection 8(b)(1) of the Plan.

3.      ADMINISTRATION.

        (a) The Plan shall be administered by the Board unless and until the
Board delegates administration to a Committee, as provided in subsection 3(c).
Any interpretation of the Plan by the Board and any decision by the Board under
the Plan shall be final and binding on all persons.

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

                (1) To determine from time to time which of the persons eligible
under the Plan shall be granted Stock Awards; when and how each Stock Award
shall be granted; whether a Stock Award will be an Option, a stock bonus, a
right to purchase restricted stock, a Stock Appreciation Right, or a combination
of the foregoing; the provisions of each Stock Award granted (which need not be
identical), including the time or times when a person shall be permitted to
receive stock pursuant to a Stock Award; whether a person shall be permitted to
receive stock upon exercise of an Independent Stock Appreciation Right; and the
number of shares with respect to which a Stock Award shall be granted to each
such person.

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

                (3) To amend the Plan or a Stock Award as provided in Section
14.

                (4) Generally, to exercise such powers and to perform such acts
as the Board deems necessary or expedient to promote the best interests of the
Company which are not in conflict with the provisions of the Plan.

        (c) The Board may delegate administration of the Plan to a committee
composed of not fewer than two (2) members (the "Committee"), all of the members
of which Committee may be, in the discretion of the Board, Non-Employee
Directors and may also be, in the discretion of the Board, Outside Directors. If
administration is delegated to a Committee, the Committee shall have, in
connection with the administration of the Plan, the powers theretofore possessed
by the


                                       4.
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Board (and references in this Plan to the Board shall thereafter be to the
Committee), subject, however, to such resolutions, not inconsistent with the
provisions of the Plan, as may be adopted from time to time by the Board. The
Board may abolish the Committee at any time and revest in the Board the
administration of the Plan. Notwithstanding anything in this Section 3 to the
contrary, at any time the Board or the Committee may delegate to a committee of
one or more members of the Board the authority to grant Stock Awards to eligible
persons who (1) are not then subject to Section 16 of the Exchange Act and/or
(2) are either (i) not then Covered Employees and are not expected to be Covered
Employees at the time of recognition of income resulting from such Stock Award,
or (ii) not persons with respect to whom the Company wishes to avoid the
application of Section 162(m) of the Code.

4.      SHARES SUBJECT TO THE PLAN.

        (a) Subject to the provisions of Section 13 relating to adjustments upon
changes in stock, the stock that may be issued pursuant to Stock Awards shall
not exceed in the aggregate of four million two hundred thousand (4,200,000)
shares of the Company's common stock. If any Stock Award shall for any reason
expire or otherwise terminate, in whole or in part, without having been
exercised in full, the stock not acquired under such Stock Award shall revert to
and again become available for issuance under the Plan. Shares subject to Stock
Appreciation Rights exercised in accordance with Section 8 of the Plan shall not
be available for subsequent issuance under the Plan.

        (b) The stock subject to the Plan may be unissued shares or reacquired
shares, bought on the market or otherwise.

5.      ELIGIBILITY.

        (a) Stock Appreciation Rights may be granted only to Non-Officer
Employees. Stock Awards other than Stock Appreciation Rights appurtenant thereto
may be granted to Non-Officer Employees or Consultants.

        (b) For purposes of this Plan, Officers and Directors shall not be
eligible to receive any Stock Awards under the Plan.

        (c) Subject to the provisions of Section 13 relating to adjustments upon
changes in stock, no person shall be eligible to be granted Options and Stock
Appreciation Rights covering more than three hundred thousand (300,000) shares
of the Company's common stock in any calendar year.

        (d) CONSULTANTS.

                (i) A Consultant shall not be eligible for the grant of a Stock
Award if, at the time of grant, a Form S-8 Registration Statement under the
Securities Act ("Form S-8") is not available to register either the offer or the
sale of the Company's securities to such Consultant because of the nature of the
services that the Consultant is providing to the Company, or because the
Consultant is not a natural person, or as otherwise provided by the rules
governing the use of Form S-8, unless the Company determines both (i) that such
grant (A) shall be registered in another manner under the Securities Act (e.g.,
on a Form S-3 Registration Statement) or (B) does


                                       5.
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not require registration under the Securities Act in order to comply with the
requirements of the Securities Act, if applicable, and (ii) that such grant
complies with the securities laws of all other relevant jurisdictions.

                (ii) As of April 7, 1999 Form S-8 generally is available to
consultants and advisors only if (i) they are natural persons; (ii) they provide
bona fide services to the issuer, its parents, its majority-owned subsidiaries
or majority-owned subsidiaries of the issuer's parent; and (iii) the services
are not in connection with the offer or sale of securities in a capital-raising
transaction, and do not directly or indirectly promote or maintain a market for
the issuer's securities.

6.      OPTION PROVISIONS.

        Each Option shall be in such form and shall contain such terms and
conditions as the Board shall deem appropriate. The provisions of separate
Options need not be identical, but each Option shall include (through
incorporation of provisions hereof by reference in the Option or otherwise) the
substance of each of the following provisions:

        (a) TERM. No Option shall be exercisable after the expiration of ten
(10) years from the date it was granted.

        (b) PRICE. The exercise price of each Option shall be not less than
eighty-five percent (85%) of the Fair Market Value of the stock subject to the
Option on the date the Option is granted.

        (c) CONSIDERATION. The purchase price of stock acquired pursuant to an
Option shall be paid, to the extent permitted by applicable statutes and
regulations, either (i) in cash at the time the Option is exercised, or (ii) at
the discretion of the Board or the Committee, at the time of the grant of the
Option, (A) by delivery to the Company of other common stock of the Company, (B)
according to a deferred payment or other arrangement (which may include, without
limiting the generality of the foregoing, the use of other common stock of the
Company) with the person to whom the Option is granted or to whom the Option is
transferred pursuant to subsection 6(d), or (C) in any other form of legal
consideration that may be acceptable to the Board.

        In the case of any deferred payment arrangement, interest shall be
payable at least annually and shall be charged at the minimum rate of interest
necessary to avoid the treatment as interest, under any applicable provisions of
the Code, of any amounts other than amounts stated to be interest under the
deferred payment arrangement. Further, the "par value" of any stock subject to
an Option shall not be payable pursuant to a deferred payment arrangement.

        (d) TRANSFERABILITY. nonstatutory Stock Options shall not be
transferable except by will, by the laws of descent and distribution or pursuant
to a domestic relations order satisfying the requirements of Rule 16b-3 and any
administrative interpretations or pronouncements thereunder (a "DRO"), and shall
be exercisable during the lifetime of the person to whom the Option is granted
only by such person or any transferee pursuant to a DRO. Notwithstanding the
foregoing, the person to whom the Option is granted may, by delivering written
notice to the Company, in a form satisfactory to the Company, designate a third
party who, in the event of the death of the Optionee, shall thereafter be
entitled to exercise the Option.


                                       6.
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        (e) VESTING. The total number of shares of stock subject to an Option
may, but need not, be allotted in periodic installments (which may, but need
not, be equal). The Option Agreement may provide that from time to time during
each of such installment periods, the Option may become exercisable ("vest")
with respect to some or all of the shares allotted to that period, and may be
exercised with respect to some or all of the shares allotted to such period
and/or any prior period as to which the Option became vested but was not fully
exercised. The Option may be subject to such other terms and conditions on the
time or times when it may be exercised (which may be based on performance or
other criteria) as the Board may deem appropriate. The provisions of this
subsection 6(e) are subject to any Option provisions governing the minimum
number of shares as to which an Option may be exercised.

        (f) TERMINATION OF EMPLOYMENT OR RELATIONSHIP AS AN EMPLOYEE OR
CONSULTANT. In the event an Optionee's Continuous Status as an Employee or
Consultant terminates (other than upon the Optionee's death or disability), the
Optionee may exercise his or her Option (to the extent that the Optionee was
entitled to exercise it at the date of termination) but only within such period
of time ending on the earlier of (i) the date three (3) months after the
termination of the Optionee's Continuous Status as an Employee or Consultant (or
such longer or shorter period specified in the Option Agreement), or (ii) the
expiration of the term of the Option as set forth in the Option Agreement. If,
after termination, the Optionee does not exercise his or her Option within the
time specified in the Option Agreement, the Option shall terminate, and the
shares covered by such Option shall revert to and again become available for
issuance under the Plan.

        An Optionee's Option Agreement may also provide that if the exercise of
the Option following the termination of the Optionee's Continuous Status as an
Employee or Consultant (other than upon the Optionee's death or disability)
would result in liability under Section 16(b) of the Exchange Act, then the
Option shall terminate on the earlier of (i) the expiration of the term of the
Option set forth in the Option Agreement, or (ii) the tenth (10th) day after the
last date on which such exercise would result in such liability under Section
16(b) of the Exchange Act. Finally, an Optionee's Option Agreement may also
provide that if the exercise of the Option following the termination of the
Optionee's Continuous Status as an Employee or Consultant (other than upon the
Optionee's death or disability) would be prohibited at any time solely because
the issuance of shares would violate the registration requirements under the
Act, then the Option shall terminate on the earlier of (i) the expiration of the
term of the Option set forth in the first paragraph of this subsection 6(f), or
(ii) the expiration of a period of three (3) months after the termination of the
Optionee's Continuous Status as an Employee or Consultant during which the
exercise of the Option would not be in violation of such registration
requirements.

        (g) DISABILITY OF OPTIONEE. In the event an Optionee's Continuous Status
as an Employee or Consultant terminates as a result of the Optionee's
disability, the Optionee may exercise his or her Option (to the extent that the
Optionee was entitled to exercise it at the date of termination), but only
within such period of time ending on the earlier of (i) the date twelve (12)
months following such termination (or such longer or shorter period specified in
the Option Agreement), or (ii) the expiration of the term of the Option as set
forth in the Option Agreement. 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 and again become available
for issuance under the Plan. If, after termination, the Optionee does not
exercise his or


                                       7.
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her Option within the time specified herein, the Option shall terminate, and the
shares covered by such Option shall revert to and again become available for
issuance under the Plan.

        (h) DEATH OF OPTIONEE. In the event of the death of an Optionee during,
or within a period specified in the Option after the termination of, the
Optionee's Continuous Status as an Employee or Consultant, the Option may be
exercised (to the extent the Optionee was entitled to exercise the Option at the
date of death) by the Optionee's estate, by a person who acquired the right to
exercise the Option by bequest or inheritance or by a person designated to
exercise the option upon the Optionee's death pursuant to subsection 6(d), but
only within the period ending on the earlier of (i) the date twelve (12) months
following the date of death (or such longer or shorter period specified in the
Option Agreement), or (ii) the expiration of the term of such Option as set
forth in the Option Agreement. 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 revert to and again become available
for issuance under the Plan. If, after death, the Option is not exercised within
the time specified herein, the Option shall terminate, and the shares covered by
such Option shall revert to and again become available for issuance under the
Plan.

        (i) EARLY EXERCISE. The Option may, but need not, include a provision
whereby the Optionee may elect at any time while an Employee or Consultant to
exercise the Option as to any part or all of the shares subject to the Option
prior to the full vesting of the Option. Any unvested shares so purchased may be
subject to a repurchase right in favor of the Company or to any other
restriction the Board determines to be appropriate.

        (j) RE-LOAD OPTIONS. Without in any way limiting the authority of the
Board or Committee to make or not to make grants of Options hereunder, the Board
or Committee shall have the authority (but not an obligation) to include as part
of any Option Agreement a provision entitling the Optionee to a further Option
(a "Re-Load Option") in the event the Optionee exercises the Option evidenced by
the Option agreement, in whole or in part, by surrendering other shares of
common stock in accordance with this Plan and the terms and conditions of the
Option Agreement. Any such Re-Load Option (i) shall be for a number of shares
equal to the number of shares surrendered as part or all of the exercise price
of such Option; (ii) shall have an expiration date which is the same as the
expiration date of the Option the exercise of which gave rise to such Re-Load
Option; and (iii) shall have an exercise price which is equal to one hundred
percent (100%) of the Fair Market Value of the common stock subject to the
Re-Load Option on the date of exercise of the original Option.

        Any such Re-Load Option shall be a nonstatutory Stock Option. Any such
Re-Load Option shall be subject to the availability of sufficient shares under
subsection 4(a) and shall be subject to such other terms and conditions as the
Board or Committee may determine which are not inconsistent with the express
provisions of the Plan regarding the terms of Options.

7.      TERMS OF STOCK BONUSES AND PURCHASES OF RESTRICTED STOCK.

        Each stock bonus or restricted stock purchase agreement shall be in such
form and shall contain such terms and conditions as the Board or the Committee
shall deem appropriate. The terms and conditions of stock bonus or restricted
stock purchase agreements may change from


                                       8.
<PAGE>

time to time, and the terms and conditions of separate agreements need not be
identical, but each stock bonus or restricted stock purchase agreement shall
include (through incorporation of provisions hereof by reference in the
agreement or otherwise) the substance of each of the following provisions as
appropriate:

        (a) PURCHASE PRICE. The purchase price under each restricted stock
purchase agreement shall be such amount as the Board or Committee shall
determine and designate in such agreement but in no event shall the purchase
price be less than eighty-five percent (85%) of the stock's Fair Market Value on
the date such award is made. Notwithstanding the foregoing, the Board or the
Committee may determine that eligible participants in the Plan may be awarded
stock pursuant to a stock bonus agreement in consideration for past services
actually rendered to the Company for its benefit.

        (b) TRANSFERABILITY. No rights under a stock bonus or restricted stock
purchase agreement shall be transferable except by will or the laws of descent
and distribution or pursuant to a qualified domestic relations order satisfying
the requirements of Rule 16b-3 and any administrative interpretations or
pronouncements thereunder, so long as stock awarded under such agreement remains
subject to the terms of the agreement.

        (c) CONSIDERATION. The purchase price of stock acquired pursuant to a
stock purchase agreement shall be paid either: (i) in cash at the time of
purchase; (ii) at the discretion of the Board or the Committee, according to a
deferred payment or other arrangement with the person to whom the stock is sold;
or (iii) in any other form of legal consideration that may be acceptable to the
Board or the Committee in its discretion. Notwithstanding the foregoing, the
Board or the Committee to which administration of the Plan has been delegated
may award stock pursuant to a stock bonus agreement in consideration for past
services actually rendered to the Company or for its benefit.

        (d) VESTING. Shares of stock sold or awarded under the Plan may, but
need not, be subject to a repurchase option in favor of the Company in
accordance with a vesting schedule to be determined by the Board or the
Committee.

        (e) TERMINATION OF EMPLOYMENT OR RELATIONSHIP AS AN EMPLOYEE OR
CONSULTANT. In the event a Participant's Continuous Status as an Employee or
Consultant terminates, the Company may repurchase or otherwise reacquire any or
all of the shares of stock held by that person which have not vested as of the
date of termination under the terms of the stock bonus or restricted stock
purchase agreement between the Company and such person.

8.      STOCK APPRECIATION RIGHTS.

        (a) The Board or Committee shall have full power and authority,
exercisable in its sole discretion, to grant Stock Appreciation Rights under the
Plan to Employees and Consultants. To exercise any outstanding Stock
Appreciation Right, the holder must provide written notice of exercise to the
Company in compliance with the provisions of the Stock Award Agreement
evidencing such right. If a Stock Appreciation Right is granted to an individual
who is at the time subject to Section 16(b) of the Exchange Act (a "Section
16(b) Insider"), the Stock Award Agreement of grant shall incorporate all the
terms and conditions at the time necessary to assure


                                       9.
<PAGE>

that the subsequent exercise of such right shall qualify for the safe-harbor
exemption from short-swing profit liability provided by Rule 16b-3 promulgated
under the Exchange Act (or any successor rule or regulation). Except as provided
in subsection 5(d), no limitation shall exist on the aggregate amount of cash
payments the Company may make under the Plan in connection with the exercise of
Stock Appreciation Rights.

        (b) Three types of Stock Appreciation Rights shall be authorized for
issuance under the Plan:

                (1) TANDEM STOCK APPRECIATION RIGHTS. Tandem Stock Appreciation
Rights will be granted appurtenant to an Option, and shall, except as
specifically set forth in this Section 8, be subject to the same terms and
conditions applicable to the particular Option grant to which it pertains.
Tandem Stock Appreciation Rights will require the holder to elect between the
exercise of the underlying Option for shares of stock and the surrender, in
whole or in part, of such Option for an appreciation distribution. The
appreciation distribution payable on the exercised Tandem Right shall be in cash
(or, if so provided, in an equivalent number of shares of stock based on Fair
Market Value on the date of the Option surrender) in an amount up to the excess
of (A) the Fair Market Value (on the date of the Option surrender) of the number
of shares of stock covered by that portion of the surrendered Option in which
the Optionee is vested over (B) the aggregate exercise price payable for such
vested shares.

                (2) CONCURRENT STOCK APPRECIATION RIGHTS. Concurrent Rights will
be granted appurtenant to an Option and may apply to all or any portion of the
shares of stock subject to the underlying Option and shall, except as
specifically set forth in this Section 8, be subject to the same terms and
conditions applicable to the particular Option grant to which it pertains. A
Concurrent Right shall be exercised automatically at the same time the
underlying Option is exercised with respect to the particular shares of stock to
which the Concurrent Right pertains. The appreciation distribution payable on an
exercised Concurrent Right shall be in cash (or, if so provided, in an
equivalent number of shares of stock based on Fair Market Value on the date of
the exercise of the Concurrent Right) in an amount equal to such portion as
shall be determined by the Board or the Committee at the time of the grant of
the excess of (A) the aggregate Fair Market Value (on the date of the exercise
of the Concurrent Right) of the vested shares of stock purchased under the
underlying Option which have Concurrent Rights appurtenant to them over (B) the
aggregate exercise price paid for such shares.

                (3) INDEPENDENT STOCK APPRECIATION RIGHTS. Independent Rights
will be granted independently of any Option and shall, except as specifically
set forth in this Section 8, be subject to the same terms and conditions
applicable to Options as set forth in Section 6. They shall be denominated in
share equivalents. The appreciation distribution payable on the exercised
Independent Right shall be not greater than an amount equal to the excess of (A)
the aggregate Fair Market Value (on the date of the exercise of the Independent
Right) of a number of shares of Company stock equal to the number of share
equivalents in which the holder is vested under such Independent Right, and with
respect to which the holder is exercising the Independent Right on such date,
over (B) the aggregate Fair Market Value (on the date of the grant of the
Independent Right) of such number of shares of Company stock. The appreciation
distribution payable on the exercised Independent Right shall be in cash or, if
so provided, in an


                                      10.
<PAGE>

equivalent number of shares of stock based on Fair Market Value on the date of
the exercise of the Independent Right.

9.      CANCELLATION AND RE-GRANT OF OPTIONS.

        (a) The Board or the Committee shall have the authority to effect, at
any time and from time to time, (i) the repricing of any outstanding Options
and/or any Stock Appreciation Rights under the Plan and/or (ii) with the consent
of any adversely affected holders of Options and/or Stock Appreciation Rights,
the cancellation of any outstanding Options and/or any Stock Appreciation Rights
under the Plan and the grant in substitution therefor of new Options and/or
Stock Appreciation Rights under the Plan covering the same or different numbers
of shares of stock, but having an exercise price per share not less than
eighty-five percent (85%) of the Fair Market Value for a nonstatutory Stock
Option. Notwithstanding the foregoing, the Board or the Committee may grant an
Option and/or Stock Appreciation Right with an exercise price lower than that
set forth above if such Option and/or Stock Appreciation Right is granted as
part of a transaction to which section 424(a) of the Code applies.

        (b) Shares subject to an Option or Stock Appreciation Right canceled
under this Section 9 shall continue to be counted against the maximum award of
Options and Stock Appreciation Rights permitted to be granted pursuant to
subsection 5(d) of the Plan. The repricing of an Option and/or Stock
Appreciation Right under this Section 9, resulting in a reduction of the
exercise price, shall be deemed to be a cancellation of the original Option
and/or Stock Appreciation Right and the grant of a substitute Option and/or
Stock Appreciation Right; in the event of such repricing, both the original and
the substituted Options and Stock Appreciation Rights shall be counted against
the maximum awards of Options and Stock Appreciation Rights permitted to be
granted pursuant to subsection 5(d) of the Plan.

10.     COVENANTS OF THE COMPANY.

        (a) During the terms of the Stock Awards, the Company shall keep
available at all times the number of shares of stock required to satisfy such
Stock Awards.

        (b) The Company shall seek to obtain from each regulatory commission or
agency having jurisdiction over the Plan such authority as may be required to
issue and sell shares of stock upon exercise of the Stock Award; provided,
however, that this undertaking shall not require the Company to register under
the Securities Act of 1933, as amended (the "Securities Act") either the Plan,
any Stock Award or any stock issued or issuable pursuant to any such Stock
Award. If, after reasonable efforts, the Company is unable to obtain from any
such regulatory commission or agency the authority which counsel for the Company
deems necessary for the lawful issuance and sale of stock under the Plan, the
Company shall be relieved from any liability for failure to issue and sell stock
upon exercise of such Stock Awards unless and until such authority is obtained.

11.     USE OF PROCEEDS FROM STOCK.

        Proceeds from the sale of stock pursuant to Stock Awards shall
constitute general funds of the Company.


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<PAGE>

12.     MISCELLANEOUS.

        (a) The Board shall have the power to accelerate the time at which a
Stock Award may first be exercised or the time during which a Stock Award or any
part thereof will vest pursuant to subsection 6(e), 7(d) or 8(b),
notwithstanding the provisions in the Stock Award stating the time at which it
may first be exercised or the time during which it will vest.

        (b) Neither an Employee, a Consultant nor any person to whom a Stock
Award is transferred in accordance with the Plan shall be deemed to be the
holder of, or to have any of the rights of a holder with respect to, any shares
subject to such Stock Award unless and until such person has satisfied all
requirements for exercise of the Stock Award pursuant to its terms.

        (c) Nothing in the Plan or any instrument executed or Stock Award
granted pursuant thereto shall confer upon any Employee, Consultant or other
holder of Stock Awards any right to continue in the employ of the Company or any
Affiliate or to continue acting as a Consultant or shall affect the right of the
Company or any Affiliate to terminate the employment of any Employee with or
without notice and with or without cause, or the right to terminate the
relationship of any Consultant pursuant to the terms of such Consultant's
agreement with the Company or Affiliate.

        (d) The Company may require any person to whom a Stock Award is granted,
or any person to whom a Stock Award is transferred in accordance with the Plan,
as a condition of exercising or acquiring stock under any Stock Award, (1) to
give written assurances satisfactory to the Company as to such person's
knowledge and experience in financial and business matters and/or to employ a
purchaser representative reasonably satisfactory to the Company who is
knowledgeable and experienced in financial and business matters, and that he or
she is capable of evaluating, alone or together with the purchaser
representative, the merits and risks of exercising the Stock Award; and (2) to
give written assurances satisfactory to the Company stating that such person is
acquiring the stock subject to the Stock Award for such person's own account and
not with any present intention of selling or otherwise distributing the stock.
The foregoing requirements, and any assurances given pursuant to such
requirements, shall be inoperative if (i) the issuance of the shares upon the
exercise or acquisition of stock under the Stock Award has been registered under
a then currently effective registration statement under the Securities Act, or
(ii) as to any particular requirement, a determination is made by counsel for
the Company that such requirement need not be met in the circumstances under the
then applicable securities laws. The Company may, upon advice of counsel to the
Company, place legends on stock certificates issued under the Plan as such
counsel deems necessary or appropriate in order to comply with applicable
securities laws, including, but not limited to, legends restricting the transfer
of the stock.

        (e) To the extent provided by the terms of a Stock Award Agreement, the
person to whom a Stock Award is granted may satisfy any federal, state or local
tax withholding obligation relating to the exercise or acquisition of stock
under a Stock Award by any of the following means or by a combination of such
means: (1) tendering a cash payment; (2) authorizing the Company to withhold
shares from the shares of the common stock otherwise issuable to the


                                      12.
<PAGE>

participant as a result of the exercise or acquisition of stock under the Stock
Award; or (3) delivering to the Company owned and unencumbered shares of the
common stock of the Company.

13.     ADJUSTMENTS UPON CHANGES IN STOCK.

        (a) If any change is made in the stock subject to the Plan, or subject
to any Stock Award, without the receipt of consideration by the Company (through
merger, consolidation, reorganization, recapitalization, reincorporation, stock
dividend, dividend in property other than cash, stock split, liquidating
dividend, combination of shares, exchange of shares, change in corporate
structure or other transaction not involving the receipt of consideration by the
Company), the Plan will be appropriately adjusted in the class(es) and maximum
number of shares subject to the Plan pursuant to subsection 4(a) and the maximum
number of shares subject to award to any person during any calendar year
pursuant to subsection 5(d), and the outstanding Stock Awards will be
appropriately adjusted in the class(es) and number of shares and price per share
of stock subject to such outstanding Stock Awards. Such adjustments shall be
made by the Board or the Committee, the determination of which shall be final,
binding and conclusive. (The conversion of any convertible securities of the
Company shall not be treated as a "transaction not involving the receipt of
consideration by the Company".)

        (b) In the event of: (1) a dissolution, liquidation or sale of all or
substantially all of the assets of the Company; (2) a merger or consolidation in
which the Company is not the surviving corporation; or (3) a reverse merger in
which the Company is the surviving corporation but the shares of the Company's
common stock outstanding immediately preceding the merger are converted by
virtue of the merger into other property, whether in the form of securities,
cash or otherwise, then to the extent permitted by applicable law: (i) any
surviving corporation or an Affiliate of such surviving corporation shall assume
any Stock Awards outstanding under the Plan or shall substitute similar Stock
Awards for those outstanding under the Plan, or (ii) such Stock Awards shall
continue in full force and effect. In the event any surviving corporation and
its Affiliates refuse to assume or continue such Stock Awards, or to substitute
similar Stock Awards for those outstanding under the Plan, then, with respect to
Stock Awards held by persons then performing services as Employees or
Consultants, the time during which such Stock Awards may be exercised shall be
accelerated and the Stock Awards terminated if not exercised prior to such
event.

14.     AMENDMENT OF THE PLAN AND STOCK AWARDS.

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

        (b) Rights and obligations under any Stock Award granted before
amendment of the Plan shall not be impaired by any amendment of the Plan unless
(i) the Company requests the consent of the person to whom the Stock Award was
granted and (ii) such person consents in writing.

        (c) The Board at any time, and from time to time, may amend the terms of
any one or more Stock Award; provided, however, that the rights and obligations
under any Stock Award


                                      13.
<PAGE>

shall not be impaired by any such amendment unless (i) the Company requests the
consent of the person to whom the Stock Award was granted and (ii) such person
consents in writing.

15.     TERMINATION OR SUSPENSION OF THE PLAN.

        (a) The Board may suspend or terminate the Plan at any time. Unless
sooner terminated, the Plan shall terminate ten (10) years from the date the
Plan is adopted by the Board. No Stock Awards may be granted under the Plan
while the Plan is suspended or after it is terminated.

        (b) Rights and obligations under any Stock Award granted while the Plan
is in effect shall not be impaired by suspension or termination of the Plan,
except with the consent of the person to whom the Stock Award was granted.

16.     EFFECTIVE DATE OF PLAN.

        The Plan shall become effective as determined by the Board.




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