Document:

<PAGE>
                                                                   Exhibit 4.2.2

                                JOINDER AGREEMENT

         WHEREAS, the undersigned Silicon Valley Bank (the "Joining Party") and
Nanosys, Inc., a Delaware corporation (the "Company"), have entered into a
certain Loan and Security Agreement, dated as of May 17, 2002, and certain other
related agreements contemplated thereby, pursuant to which, among other things,
the Company will issue to the Joining Party a Warrant (the "Warrant") to
purchase up to 41,250 shares of the Company's Series B Preferred Stock, $.001
par value per share (the "Shares");

         WHEREAS, the parties hereto desire the Joining Party to have certain
"piggyback" registration rights with respect to the shares of the Company's
common stock, $.001 par value per share ("Common Stock"), issuable upon
conversion of the Shares (and with respect to the Shares, at all times when the
Class (as defined in the Warrant) is Common Stock) pursuant to Section 2.3 of
that certain Amended and Restated Investors' Rights Agreement, dated as of
January 18, 2002, among the Company and the other parties named therein, as
amended (the "Rights Agreement"), and that the Joining Party be added to the
Rights Agreement as a party thereto for the purpose of granting such "piggyback"
registration rights; and

         WHEREAS, Section 4.2 of the Rights Agreement allows the Company and the
holders of a majority (the "Majority Holders") of the Registrable Securities, as
such term is defined in the Rights Agreement, to add parties to the Right
Agreement by written consent.

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration, the receipt and sufficiency of which is hereby mutually
acknowledged by the parties hereto, the parties hereby covenant and agree as
follows:

         1. The shares of Common Stock issuable upon conversion of the Shares,
and the Shares at all times when the Class is Common Stock shall constitute
"Registrable Securities," as such term is defined in Section 2.1(e) of the
Rights Agreement, for all intents and purposes of the registration rights and
related provisions and obligations set forth in Sections 2.1 and 2.3, Sections
2.5 through 2.14 inclusive and Section 4 of the Rights Agreement.

         2. The Joining Party shall be treated for all purposes under Section
2.1 and 2.3, Sections 2.5 through 2.14 inclusive, and Section 4 of the Rights
Agreement as a "Holder," as such term is defined in Section 2.1(b) of the Rights
Agreement.

         3. The Joining Party agrees to be bound by the terms and conditions of
Sections 2.1 and 2.3, Sections 2.5 through 2.14 inclusive and Section 4 of the
Rights Agreement and shall succeed to and assume all of the rights and
obligations of a Holder of Registrable Securities for all intents and purposes
of such Sections, provided that, in the case of Section 4.1 of the Rights
Agreement, the Joining Party agrees to be bound as an "Investor" in the event
the Joining Party proposes to transfer the Shares or the Warrant to a transferee
and, provided further, that the

<PAGE>

Joining Party shall not, and shall not be deemed to, possess or be able to
transfer any rights set forth in the Rights Agreement (including, without
limitation, any Preemptive Rights set forth in Section 3 of the Rights
Agreement) other than the "piggyback" registration rights the Joining Party
possesses pursuant to this Joinder Agreement.

         4. Notwithstanding the provisions of Section 2.3(a) of the Rights
Agreement, the Company shall give notice of any registration initiated pursuant
to Section 2.2 of the Rights Agreement to the Joining Party in accordance with
the notice provisions of said Section 2.3(a) and shall (upon receipt by the
Company of a written request from the Joining Party within 20 days after Joining
Party's receipt of such notice) include the Joining Party's Registrable
Securities in such registration, subject to the terms, conditions and
limitations of the portions of the Rights Agreement to which the Joining Party
is made a party hereby; provided, that in the case of a registration initiated
pursuant to Section 2.2 of the Rights Agreement, the Joining Party shall be
subject to the terms, conditions and limitations set forth in Section 2.2 in
addition to the portions of the Rights Agreement to which the Joining Party is
made a party hereby; and provided further, that the Joining Party shall in no
event be, or be deemed to be, an "Initiating Holder" under Sections 2.1(e) or
2.2 of the Rights Agreement..

         This Joinder Agreement may be executed in any number of separate
counterparts and all of said counterparts taken together shall be deemed to
constitute one and the same instrument.

                [REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

<PAGE>

         IN WITNESS WHEREOF, the parties have duly executed this Joinder
Agreement as of May 17, 2002.

                                                              "JOINING PARTY":

                                          SILICON VALLEY BANK

                                          By:    /s/ Michael J. Hancwich
                                                -----------------------------
                                          Name:  Michael J. Hancwich
                                                -----------------------------
                                          Title: SVP
                                                -----------------------------

                                          "COMPANY":

                                          NANOSYS, INC.

                                          By:    /s/ Lawrence Bock
                                                -----------------------------
                                          Name:  Lawrence Bock
                                                -----------------------------
                                          Title: CEO
                                                -----------------------------

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          ARCH VENTURE FUND V, L.P.

                          By:   ARCH Venture Partners V, L.P.
                          Its:  General Partner

                                     By:    ARCH Venture Partners V, L.L.C.
                                     Its:  General Partner

                                     By: /s/ Clint Bybee
                                        -----------------------------
                                         Managing Director

                          ARCH V ENTREPRENEURS FUND, L.P.

                          By:   ARCH Venture Partners V, L.P.
                          Its:  General Partner

                                     By:   ARCH Venture Partners V, L.L.C.
                                     Its:  General Partner

                                     By: /s/ Clint Bybee
                                        -----------------------------
                                         Managing Director

<PAGE>

                          "MAJORITY HOLDERS":

                          POLARIS VENTURE PARTNERS III, L.P.

                          By:   Polaris Venture Management Co. III, L.L.C.
                          Its:  General Partner

                                     By: /s/ William E. Bilodeau
                                        -----------------------------
                                        Name:  William E. Bilodeau
                                        Title: Attorney-in-fact

                          POLARIS VENTURE PARTNERS
                          ENTREPRENEURS' FUND III, L.P.

                          By:   Polaris Venture Management Co. III, L.L.C.
                          Its:  General Partner

                                     By: /s/ William E. Bilodeau
                                        -----------------------------
                                        Name:  William E. Bilodeau
                                        Title: Attorney-in-fact

                          POLARIS VENTURE PARTNERS
                          FOUNDERS' FUND III, L.P.

                          By:     Polaris Venture Management Co. III, L.L.C.
                          Its:    General Partner

                                     By: /s/ William E. Bilodeau
                                        -----------------------------
                                        Name:  William E. Bilodeau
                                        Title: Attorney-in-fact

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          VENROCK ASSOCIATES

                                     By: /s/ Bryan E. Roberts
                                        -----------------------------
                                       Name:  Bryan E. Roberts
                                       Title: General Partner

                          VENROCK ASSOCIATES III, L.P.

                          By:   Venrock Management III LLC
                          Its:  General Partner

                                     By: /s/ Bryan E. Roberts
                                        -----------------------------
                                       Name:  Bryan E. Roberts
                                       Title: Member

                          VENROCK ENTREPRENEURS FUND III, L.P.

                          By:   VEF Management III LLC
                          Its:  General Partner

                                     By: /s/ Bryan E. Roberts
                                        -----------------------------
                                        Name:  Bryan E. Roberts
                                        Title: Member

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          CW VENTURES III, L.P.

                                     By: /s/ Lawrence Bock
                                         -----------------------------
                                         CW Partners IV, L.L.C.
                                         General Partner

                          CW VENTURES III - A CO-INVESTMENT FUND, L.P.

                                     By: /s/ Lawrence Bock
                                         -----------------------------
                                         CW Partners IV, L.L.C.
                                         General Partner

                          J.P. MORGAN/CW VENTURES III
                          (NANOSYS), L.P.

                                     By: /s/ Lawrence Bock
                                         -----------------------------
                                         CW Partners IV, L.L.C.
                                         General Partner

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          PROSPECT VENTURE PARTNERS II, L.P.

                          By:   Prospect Management Co. II, LLC
                          Its:  General Partner

                                     By: /s/ James Tananbaum
                                         -----------------------------
                                         Name:  James Tananbaum
                                         Title: Managing Member

                          PROSPECT ASSOCIATES II, L.P.

                          By:   Prospect Management Co. II, LLC
                          Its:  General Partner

                                     By: /s/ James Tananbaum
                                         -----------------------------
                                         Name:  James Tananbaum
                                         Title: Managing Member

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          /s/ Charles Lieber
                          -------------------------------------------
                          DR. CHARLES LIEBER

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          /s/ Hongkun Park
                          -------------------------------------------
                          DR. HONGKUN PARK

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          /s/ Robert M. Metcalfe
                          -------------------------------------------
                          ROBERT M. METCALFE

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          -------------------------------------------
                          ALAN CHOW C/F
                          TIFFANY CHOW UGMA CA
                          "INVESTORS"

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          -------------------------------------------
                          ALAN CHOW C/F
                          HARRISON CHOW UGMA CA

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          -------------------------------------------
                          ALAN CHOW C/F
                          STEPHANIE CHOW UGMA CA

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          MCKENNA VENTURES, LP

                          BY:
                               -----------------------------------

                          TITLE:
                                  --------------------------------

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          -------------------------------------------
                          MICHAEL O'DONNELL

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          -------------------------------------------
                          R. RANDOLPH SCOTT

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          -------------------------------------------
                          KAREN L. VERGURA

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          WS INVESTMENT COMPANY, LLC

                          BY:
                               -----------------------------------

                          TITLE:
                                  --------------------------------

                     [Signature Page to Joinder Agreement]

<PAGE>

                          "MAJORITY HOLDERS":

                          ALEXANDRIA EQUITIES, LLC, a Delaware limited liability
                          company

                          By: ALEXANDRIA REAL ESTATE
                              EQUITIES, INC., a Maryland corporation,
                              managing member

                              By:
                                 --------------------------------------
                                 Laurie A. Allen, Senior Vice President,
                                 Business Development & Legal Affairs

                     [Signature Page to Joinder Agreement]<PAGE>

                                                                    EXHIBIT 10.1

                                  NANOSYS, INC.

                             2001 AMENDED STOCK PLAN

         1.       Purposes of the Plan. The purposes of this 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
hereof.

                  (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 other country or jurisdiction where Options or Stock Purchase Rights are
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

                           (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 of Directors or of
other individuals satisfying Applicable Laws appointed by the Board in
accordance with Section 4 hereof.

<PAGE>

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

                  (h)      "Company" means Nanosys, Inc., a Delaware
corporation.

                  (i)      "Consultant" means any person who is engaged by the
Company or any Parent or Subsidiary to render consulting or advisory services to
such entity.

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

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

                  (l)      "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.

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

                  (n)      "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, its Fair
Market Value shall be the mean between the high bid and low asked prices for the
Common Stock on the day of determination; or (iii) In the absence of an
established market for the Common Stock, the Fair Market Value thereof shall be
determined in good faith by the Administrator.

                  (o)      "Incentive Stock Option" means an Option intended to
qualify as an incentive stock option within the meaning of Section 422 of the
Code.

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

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

                  (r)      "Option Agreement" means a written or electronic
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.

                                                                             -2-

<PAGE>

                  (s)      "Optioned Stock" means the Common Stock subject to an
Option or a Stock Purchase Right.

                  (t)      "Optionee" means the holder of an outstanding Option
or Stock Purchase Right granted under the Plan.

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

                  (v)      "Plan" means this 2001 Amended Stock Plan.

                  (w)      "Restricted Stock" means Shares issued pursuant to a
Stock Purchase Right or Shares of restricted stock issued pursuant to an Option.

                  (x)      "Restricted Stock Purchase Agreement" means a written
agreement between the Company and the Optionee evidencing the terms and
restrictions applying to Shares 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.

                  (y)      "Securities Act means the Securities Act of 1933, as
amended.

                  (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 below.

                  (bb)     "Stock Purchase Right" means a right to purchase
Common Stock pursuant to Section 11 below.

                  (cc)     "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 that may be
subject to option and sold under the Plan is 9,137,000 Shares. In no event shall
the number of Shares issued pursuant to Incentive Stock Options exceed 9,137,000
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, the unpurchased Shares that
were subject thereto shall become available for future grant or sale under the
Plan (unless the Plan has terminated). However, Shares that have actually been
issued under the Plan, upon exercise of either an Option or Stock Purchase
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.

                                                                             -3-

<PAGE>

         4.       Administration of the Plan.

                  (a)      Administrator. The Plan shall be administered by the
Board or a Committee appointed by the Board, which Committee shall be
constituted to comply with Applicable Laws.

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

                           (i)      to determine the Fair Market Value;

                           (ii)     to select the Service Providers to whom
Options and Stock Purchase Rights may from time to time be granted hereunder;

                           (iii)    to determine the number of Shares to be
covered by each such award granted hereunder;

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

                           (v)      to determine the terms and conditions of any
Option or Stock Purchase Right 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 Common Stock relating thereto, based in each case on such
factors as the Administrator, in its sole discretion, shall determine;

                           (vi)     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 satisfying applicable foreign laws;

                           (vii)    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 minimum 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
Optionees 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;
and

                           (viii)   to construe and interpret the terms of the
Plan and Options granted pursuant to the Plan.

                  (c)      Effect of Administrator's Decision. All decisions,
determinations and interpretations of the Administrator shall be final and
binding on all Optionees.

                                                                             -4-

<PAGE>

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

         6.       Limitations.

                  (a)      Incentive Stock Option Limit. 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)      At-Will Employment. Neither the Plan nor any Option
or Stock Purchase Right shall confer upon any Optionee any right with respect to
continuing the Optionee's relationship as a Service Provider with the Company,
nor shall it interfere in any way with his or her right or the Company's right
to terminate such relationship at any time, with or without cause, and with or
without notice.

         7.       Term of Plan. Subject to shareholder approval in accordance
with Section 19, the Plan shall become effective upon its adoption by the Board.
Unless sooner terminated under Section 15, it shall continue in effect for a
term of ten (10) years from the later of (i) the effective date of the Plan, or
(ii) the earlier of the most recent board or shareholder approval of an increase
in the number of Shares reserved for issuance under the Plan.

         8.       Term of Option. The term of each Option shall be stated in the
Option Agreement; provided, however, that the term shall be no more than ten
(10) years from the date of grant thereof. In the case of an Incentive Stock
Option granted to an Optionee who, at the time the 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 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 upon exercise of an Option shall be such price as is
determined by the Administrator, but shall be subject to the following:

                           (i)      In the case of an Incentive Stock Option

                                    (A)      granted to an Employee who, at the
time of grant of such Option, 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 exercise price shall be no less than 110% of the Fair Market
Value per Share on the date of grant.

                                      -5-
<PAGE>

                                    (B)      granted to any other Employee, 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

                                    (A)      granted to a Service Provider who,
at the time of grant of such Option, 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 exercise price shall be no less than 110% of the Fair
Market Value per Share on the date of grant.

                                    (B)      granted to any other Service
Provider, the per Share exercise price shall be no less than 85% 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 other than as required above pursuant
to a merger or other corporate transaction.

                  (b)      Forms of Consideration. The consideration to be paid
for the Shares to be issued upon exercise of an Option, including the method of
payment, shall be determined by the Administrator (and, in the case of an
Incentive Stock Option, shall be determined at the time of grant). Such
consideration may consist of, without limitation, (1) cash, (2) check, (3)
promissory note, (4) other Shares, provided Shares acquired directly from the
Company (x) have been owned by the Optionee for more than six months on the date
of surrender, and (y) have a Fair Market Value on the date of surrender equal to
the aggregate exercise price of the Shares as to which such Option shall be
exercised, (5) consideration received by the Company under a cashless exercise
program implemented by the Company in connection with the Plan, or (6) any
combination of the foregoing methods of payment. In making its determination as
to the type of consideration to accept, the Administrator shall consider if
acceptance of such consideration may be reasonably expected to benefit the
Company.

         10.      Exercise of Option.

                  (a)      Procedure for Exercise; Rights as a Shareholder. Any
Option granted hereunder shall be exercisable according to the terms hereof 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. Except in the case of Options granted to officers, Directors and
Consultants, Options shall become exercisable at a rate of no less than 20% per
year over five (5) years from the date the Options are granted.

                           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 shareholder shall exist
with respect to the Shares, notwithstanding the exercise of the Option. The
Company shall issue (or cause to be issued) such

                                                                             -6-
<PAGE>

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 13 of the Plan.

                           Exercise of an Option in any manner shall result in a
decrease in 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, such Optionee may exercise his or
her Option within thirty (30) days of termination, or such longer period of time
as 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
of the Option as set forth in the Option Agreement). 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 six (6) months of termination, or such longer
period of time as 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). 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 six (6) months following
Optionee's death, or such longer period of time as specified in the Option
Agreement, to the extent that the Option is vested on the date of death (but in
no event later than the expiration of the term of such Option as set forth in
the Option Agreement) by the Optionee's designated beneficiary, provided such
beneficiary has been designated prior to Optionee's death in a form acceptable
to the Administrator. If no such beneficiary has been designated by the
Optionee, then such Option may be exercised by the personal representative of
the Optionee's estate or by the person(s) to whom the Option is transferred
pursuant to the Optionee's will or in accordance with the laws of descent and
distribution. 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. 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.

                  (e)      Leaves of Absence.

                           (i)      Unless the Administrator provides otherwise,
vesting of Options granted hereunder to officers and Directors shall be
suspended during any unpaid leave of absence.

                                                                             -7-
<PAGE>

                           (ii)     A Service Provider shall not cease to be an
Employee in the case of (A) any leave of absence approved by the Company or (B)
transfers between locations of the Company or between the Company, its Parent,
any Subsidiary, or any successor.

                           (iii)    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 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.

         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 or electronically of the terms,
conditions and restrictions related to the offer, including the number of Shares
that such person shall be entitled to purchase, the price to be paid, and the
time within which such person must accept such offer. The terms of the offer
shall comply in all respects with Section 260.140.42 of Title 10 of the
California Code of Regulations. 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
determines otherwise, the Restricted Stock Purchase Agreement shall grant the
Company a repurchase option exercisable within 90 days of the voluntary or
involuntary termination of the purchaser's service 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 such rate as the Administrator may determine.

                  (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.

                  (d)      Rights as a Shareholder. Once the Stock Purchase
Right is exercised, the purchaser shall have 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
shall 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.      Limited Transferability of Options and Stock Purchase Rights.
Unless determined otherwise by the Administrator, Options and Stock Purchase
Rights may not be sold, pledged, assigned, hypothecated, transferred, or
disposed of in any manner other than by will or the laws of descent and
distribution, and may be exercised during the lifetime of the Optionee, only by
the Optionee. If the Administrator in its sole discretion makes an Option or
Stock Purchase Right transferable, such Option or Stock Purchase Right may only
be transferred (i) by will, (ii) by the

                                                                             -8-
<PAGE>

laws of descent and distribution, or (iii) to family members (within the meaning
of Rule 701 of the Securities Act) through gifts or domestic relations orders,
as permitted by Rule 701 of the Securities Act.

         13.      Adjustments; Dissolution or Liquidation; Merger or Change in
Control.

                  (a)      Adjustments. In the event that any dividend or other
distribution (whether in the form of cash, Shares, other securities, or other
property), recapitalization, stock split, reverse stock split, reorganization,
merger, consolidation, split-up, spin-off, combination, repurchase, or exchange
of Shares or other securities of the Company, or other change in the corporate
structure of the Company affecting the Shares occurs, the Administrator, in
order to prevent diminution or enlargement of the benefits or potential benefits
intended to be made available under the Plan, may (in its sole discretion)
adjust the number and class of Shares that may be delivered under the Plan
and/or the number, class, and price of Shares covered by each outstanding Option
or Stock Purchase Right; provided, however, that the Administrator shall make
such adjustments to the extent required by Section 25102(o) of the California
Corporations Code.

                  (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. To the extent it has not been previously exercised, an
Option or Stock Purchase Right 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 substituted by the successor corporation or a Parent or Subsidiary of the
successor corporation. In the event that the successor corporation in a merger
or Change in Control refuses to assume or substitute for the Option or Stock
Purchase Right, then the Optionee shall fully vest in and 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 vested or exercisable. If
an Option or Stock Purchase Right becomes fully vested and exercisable in lieu
of assumption or substitution in the event of a merger or Change in Control, the
Administrator shall notify the Optionee in writing or electronically that such
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 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 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

                                                                             -9-
<PAGE>

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.

         14.      Time of Granting Options and Stock Purchase Rights. The date
of grant of an Option or Stock Purchase Right shall, for all purposes, be the
date on which the Administrator makes the determination granting such Option or
Stock Purchase Right, or such later date as is determined by the Administrator.
Notice of the determination shall be given to each Service Provider to whom an
Option or Stock Purchase Right is so granted 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 Board shall obtain
shareholder 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.

         16.      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 Administrator 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.

         17.      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.

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

                                                                            -10-
<PAGE>

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

         20.      Information to Optionees. The Company shall provide to each
Optionee and to each individual who acquires Shares pursuant to the Plan, not
less frequently than annually during the period such Optionee has one or more
Options or Stock Purchase Rights outstanding, and, in the case of an individual
who acquires Shares pursuant to the Plan, during the period such individual owns
such Shares, copies of annual financial statements. The Company shall not be
required to provide such statements to key employees whose duties in connection
with the Company assure their access to equivalent information.

                                                                            -11-

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00065-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00065-of-00352.parquet"}]]