Exhibit 10.23
SILVER TAIL SYSTEMS, INC.

2008 STOCK PLAN

As amended and restated on September 26, 2008
As amended by the Board of Directors on March 31, 2010
As amended by the Board of Directors on December 9, 2010
As amended by the Board of Directors on May 18, 2011
As amended by the Board of Directors on May 22, 2012
As amended by the Board of Directors on August 21, 2012

1.    Purposes of the Plan. The purposes of this 2008 Stock Plan are to attract
and retain the best available personnel for positions of substantial
responsibility, to provide additional incentive to Employees 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 of an option and subject to the
applicable provisions of Section 422 of the Code and the regulations and
interpretations promulgated thereunder. 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 its Committee appointed pursuant to
Section 4 of the Plan.

(b)    “Affiliate” means any entity that is directly or indirectly controlled by
the Company or any entity in which the Company has a significant ownership
interest as determined by the Administrator.

(c)    “Applicable Laws” means the legal requirements relating to the
administration of stock option and restricted stock purchase plans, including
under applicable U.S. state corporate laws, U.S. federal and applicable state
securities laws, other U.S. federal and state laws, the Code, any Stock Exchange
rules or regulations and the applicable laws, rules and regulations of any other
country or jurisdiction where Options or Stock Purchase Rights are granted under
the Plan, as such laws, rules, regulations and requirements shall be in place
from time to time.

(d)    “Award” means an Option or a Stock Purchase Right granted in accordance
with the terms of the Plan.

(e)    “Award Agreement” means a Restricted Stock Purchase Agreement and/or
Option Agreement.

(f)    “Board” means the Board of Directors of the Company.

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(g)    “Cause” for termination of a Participant’s Continuous Service Status will
exist if the Participant is terminated by the Company for any of the following
reasons: (i) Participant’s willful failure substantially to perform his or her
duties and responsibilities to the Company or deliberate violation of a Company
policy; (ii) Participant’s commission of any act of fraud, embezzlement,
dishonesty or any other willful misconduct that has caused or is reasonably
expected to result in material injury to the Company; (iii) unauthorized use or
disclosure by Participant of any proprietary information or trade secrets of the
Company or any other party to whom the Participant owes an obligation of
nondisclosure as a result of his or her relationship with the Company; or (iv)
Participant’s willful breach of any of his or her obligations under any written
agreement or covenant with the Company. The determination as to whether a
Participant is being terminated for Cause shall be made in good faith by the
Company and shall be final and binding on the Participant. The foregoing
definition does not in any way limit the Company’s ability to terminate a
Participant’s employment or consulting relationship at any time as provided in
Section 5(d) below, and the term “Company” will be interpreted to include any
Subsidiary, Parent or Affiliate, as appropriate.

(h)    “Change of Control” means (1) a sale of all or substantially all of the
Company’s assets, or (2) any merger, consolidation or other business combination
transaction of the Company with or into another corporation, entity or person,
other than a transaction in which the holders of at least a majority of the
shares of voting capital stock of the Company outstanding immediately prior to
such transaction continue to hold (either by such shares remaining outstanding
or by their being converted into shares of voting capital stock of the surviving
entity) a majority of the total voting power represented by the shares of voting
capital stock of the Company (or the surviving entity) outstanding immediately
after such transaction, (3) the direct or indirect acquisition (including by way
of a tender or exchange offer) by any person, or persons acting as a group, of
beneficial ownership or a right to acquire beneficial ownership of shares
representing a majority of the voting power of the then outstanding shares of
capital stock of the Company, (4) any other transaction or series of related
transactions deemed to be a “Liquidation Transaction” (as defined in the
Company’s Certificate of Incorporation, as amended from time to time) or (5) a
contested election of Directors, as a result of which or in connection with
which the persons who were Directors before such election or their nominees (the
“Incumbent Directors”) cease to constitute a majority of the Board; provided
however that if the election or nomination for election by the Company’s
stockholders, of any new Director was approved by a vote of at least 50% of the
Incumbent Directors, such new Director shall be considered as an Incumbent
Director.

(i)    “Code” means the Internal Revenue Code of 1986, as amended.

(j)    “Committee” means one or more committees or subcommittees of the Board
appointed by the Board to administer the Plan in accordance with Section 4
below.

(k)    “Common Stock” means the Common Stock of the Company.

(l)    “Company” means Silver Tail Systems, Inc., a Delaware corporation.

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(m)     “Consultant” means any person, including an advisor, who is engaged by
the Company or any Parent, Subsidiary or Affiliate to render services and is
compensated for such services, and any director of the Company whether
compensated for such services or not.

(n)    “Continuous Service Status” means the absence of any interruption or
termination of service as an Employee or Consultant. Continuous Service Status
as an Employee or Consultant shall not be considered interrupted in the case of:
(i) sick leave; (ii) military leave; (iii) any other leave of absence approved
by the Administrator, provided that such leave is for a period of not more than
ninety (90) days, unless reemployment upon the expiration of such leave is
guaranteed by contract or statute, or unless provided otherwise pursuant to
Company policy adopted from time to time; or (iv) in the case of transfers
between locations of the Company or between the Company, its Parents,
Subsidiaries, Affiliates or their respective successors. A change in status from
an Employee to a Consultant or from a Consultant to an Employee will not
constitute an interruption of Continuous Service Status. However, for Incentive
Stock Option purposes, termination of Continuous Service Status will occur when
the Employee ceases to be an employee (as determined in accordance with Section
3401(c) of the Code and the regulations promulgated thereunder) of the Company
or one of its Subsidiaries. The Administrator shall determine whether any
corporate transaction, such as a sale or spin-off of a division or business
unit, or a joint venture, shall be deemed to result in a termination of
Continuous Service Status.

(o)    “Corporate Transaction” means a sale of all or substantially all of the
Company’s assets, or a merger, consolidation or other capital reorganization or
business combination transaction of the Company with or into another
corporation, entity or person, the direct or indirect acquisition (including by
way of a tender or exchange offer) by any person, or persons acting as a group,
of beneficial ownership or a right to acquire beneficial ownership of shares
representing a majority of the voting power of the then outstanding shares of
capital stock of the Company.

(p)    “Director” means a member of the Board.

(q)    “Employee” means any person employed by the Company or any Parent or
Subsidiary, with the status of employment determined based upon such factors as
are deemed appropriate by the Administrator in its discretion, subject to any
requirements of the Code or the Applicable Laws. The payment by the Company of a
director’s fee to a Director shall not be sufficient to constitute “employment”
of such Director by the Company.

(r)    “Exchange Act” means the Securities Exchange Act of 1934, as amended.

(s)    “Fair Market Value” means, as of any date, the value of a share of Common
Stock or other property as determined by the Administrator, in its discretion,
or by the Company, in its discretion, if such determination is expressly
allocated to the Company herein, subject to the following:

(i)    If, on such date, the Common Stock is listed on a national or regional
securities exchange or market system, including without limitation the

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Nasdaq Global Market, the Fair Market Value of a share of Common Stock shall be
the closing price on such date of a share of Common Stock (or the mean of the
closing bid and asked prices of a share of Common Stock if the stock is so
quoted instead) as quoted on such exchange or market system constituting the
primary market for the Common Stock, as reported in The Wall Street Journal or
such other source as the Administrator deems reliable. If the relevant date does
not fall on a day on which the Common Stock has traded on such securities
exchange or market system, the date on which the Fair Market Value shall be
established shall be the last day on which the Common Stock was so traded prior
to the relevant date, or such other appropriate day as shall be determined by
the Administrator, in its discretion.

(ii)    If, on such date, the Common Stock is not listed on a national or
regional securities exchange or market system, the Fair Market Value of a share
of Common Stock shall be as determined by the Administrator in good faith using
a reasonable application of a reasonable valuation method without regard to any
restriction other than a restriction which, by its terms, will never lapse.

(t)    “Incentive Stock Option” means an Option intended to qualify as an
incentive stock option within the meaning of Section 422 of the Code, as
designated in the applicable Option Agreement.

(u)    “Listed Security” means any security of the Company that is listed or
approved for listing on a national securities exchange or designated or approved
for designation as a national market system security on an interdealer quotation
system by the National Association of Securities Dealers, Inc.

(v)    “Named Executive” means any individual who is a covered employee pursuant
to Section 162(m) of the Code.

(w)    “Nonstatutory Stock Option” means an Option not intended to qualify as an
Incentive Stock Option, as designated in the applicable Option Agreement.

(x)    “Option” means a stock option granted pursuant to the Plan.

(y)    “Option Agreement” means a written document, the form(s) of which shall
be approved from time to time by the Administrator, reflecting the terms of an
Option granted under the Plan and includes any documents attached to or
incorporated into such Option Agreement, including, but not limited to, a notice
of stock option grant and a form of exercise notice.

(z)    “Option Exchange Program” means a program approved by the Administrator
whereby outstanding Options are exchanged for Options with a lower exercise
price or are amended to decrease the exercise price as a result of a decline in
the Fair Market Value of the Common Stock.

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(aa)    “Optioned Stock” means the Common Stock subject to an Option.

(bb)    “Optionee” means an Employee or Consultant who receives an Option.

(cc)    “Parent” means a “parent corporation,” whether now or hereafter
existing, as defined in Section 424(e) of the Code, or any successor provision.

(dd)    “Participant” means any holder of one or more Options or Stock Purchase
Rights, or the Shares issuable or issued upon exercise of such awards, under the
Plan.

(ee)    “Plan” means this 2008 Stock Plan.

(ff)    “Reporting Person” means an officer, Director, or greater than ten
percent stockholder of the Company within the meaning of Rule 16a-2 under the
Exchange Act, who is required to file reports pursuant to Rule 16a-3 under the
Exchange Act.

(gg)    “Restricted Stock” means Shares of Common Stock acquired pursuant to a
grant of a Stock Purchase Right under Section 10 below.

(hh)    “Restricted Stock Purchase Agreement” means a written document, the
form(s) of which shall be approved from time to time by the Administrator,
reflecting the terms of a Stock Purchase Right granted under the Plan and
includes any documents attached to such document.

(ii)    “Rule 16b-3” means Rule 16b-3 promulgated under the Exchange Act, as
amended from time to time, or any successor provision.

(jj)    “Share” means a share of the Common Stock, as adjusted in accordance
with Section 13 of the Plan.

(kk)    “Stock Exchange” means any stock exchange or consolidated stock price
reporting system on which prices for the Common Stock are quoted at any given
time.

(ll)    “Stock Purchase Right” means the right to purchase or otherwise acquire
Common Stock pursuant to Section 10 below.

(mm)    “Subsidiary” means a “subsidiary corporation,” whether now or hereafter
existing, as defined in Section 424(f) of the Code, or any successor provision.

(nn)    “Ten Percent Holder” means a person who 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.

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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 sold under the Plan is
23,139,406 Shares of Common Stock. The Shares may be authorized, but unissued,
or reacquired Common Stock. If an award should expire or become unexercisable
for any reason without having been exercised in full, or is surrendered pursuant
to an Option Exchange Program, the unpurchased Shares that were subject thereto
shall, unless the Plan shall have been terminated, become available for future
grant under the Plan. In addition, any Shares of Common Stock which are retained
by the Company upon exercise of an award in order to satisfy the exercise or
purchase price for such award or any withholding taxes due with respect to such
exercise or purchase shall be treated as not issued and shall continue to be
available under the Plan. Shares issued under the Plan and later forfeited to
the Company or repurchased by the Company pursuant to any repurchase right which
the Company may have shall be available for future grant under the Plan.

4.    Administration of the Plan.

(a)    General. The Plan shall be administered by the Board or a Committee, or a
combination thereof, as determined by the Board. The Plan may be administered by
different administrative bodies with respect to different classes of
Participants and, if permitted by the Applicable Laws, the Board may authorize
one or more officers to make awards under the Plan.    

(b)    Committee Composition. If a Committee has been appointed pursuant to this
Section 4, such Committee shall continue to serve in its designated capacity
until otherwise directed by the Board. From time to time the Board may increase
the size of any Committee and appoint additional members thereof, remove members
(with or without cause) and appoint new members in substitution therefor, fill
vacancies (however caused) and remove all members of a Committee and thereafter
directly administer the Plan, all to the extent permitted by the Applicable Laws
and, in the case of a Committee administering the Plan in accordance with the
requirements of Rule 16b-3 or Section 162(m) of the Code, to the extent
permitted or required by such provisions. The Committee shall in all events
conform to any requirements of the Applicable Laws.

(c)    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, the Administrator shall have the authority, in its discretion:

(i)    to determine the Fair Market Value of the Common Stock, in accordance
with Section 2(s) of the Plan, provided that such determination shall be applied
consistently with respect to Participants under the Plan;

(ii)    to select the Employees and Consultants to whom Plan awards may from
time to time be granted;

(iii)    to determine whether and to what extent Plan awards are granted;

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(iv)    to determine the number of Shares of Common Stock to be covered by each
award granted;

(v)    to approve the form(s) of agreement(s) used under the Plan;

(vi)    to determine the terms and conditions, not inconsistent with the terms
of the Plan, of any award granted hereunder, which terms and conditions include
but are not limited to the exercise or purchase price, the time or times when
awards may be exercised (which may be based on performance criteria), any
vesting acceleration or waiver of forfeiture restrictions, any pro rata
adjustment to vesting as a result of a Participant’s transitioning from full- to
part-time service (or vice versa), and any restriction or limitation regarding
any Option, Optioned Stock, Stock Purchase Right or Restricted Stock, based in
each case on such factors as the Administrator, in its sole discretion, shall
determine;

(vii)    to determine whether and under what circumstances an Option may be
settled in cash under Section 9(c) instead of Common Stock;

(viii)    to implement an Option Exchange Program on such terms and conditions
as the Administrator in its discretion deems appropriate, provided that no
amendment or adjustment to an Option that would materially and adversely affect
the rights of any Optionee shall be made without the prior written consent of
the Optionee;

(ix)    to adjust the vesting of an Option held by an Employee or Consultant as
a result of a change in the terms or conditions under which such person is
providing services to the Company;

(x)    to construe and interpret the terms of the Plan and awards granted under
the Plan, which constructions, interpretations and decisions shall be final and
binding on all Participants; and

(xi)    in order to fulfill the purposes of the Plan and without amending the
Plan, to modify grants of Options or Stock Purchase Rights to Participants who
are foreign nationals or employed outside of the United States in order to
recognize differences in local law, tax policies or customs.

5.    Eligibility.

(a)    Recipients of Grants. Nonstatutory Stock Options and Stock Purchase
Rights may be granted to Employees and Consultants. Incentive Stock Options may
be granted only to Employees, provided that Employees of Affiliates shall not be
eligible to receive Incentive Stock Options.

(b)    Type of Option. Each Option shall be designated in the Option Agreement
as either an Incentive Stock Option or a Nonstatutory Stock Option.

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(c)    ISO $100,000 Limitation. Notwithstanding any designation under Section
5(b), to the extent that the aggregate Fair Market Value of Shares with respect
to which Options designated as Incentive Stock Options are exercisable for the
first time by any Optionee during any calendar year (under all plans of the
Company or any Parent or Subsidiary) exceeds $100,000, such excess Options shall
be treated as Nonstatutory Stock Options. For purposes of this Section 5(c),
Incentive Stock Options shall be taken into account in the order in which they
were granted, and the Fair Market Value of the Shares subject to an Incentive
Stock Option shall be determined as of the date of the grant of such Option.

(d)    No Employment Rights. The Plan shall not confer upon any Participant any
right with respect to continuation of an employment or consulting relationship
with the Company, nor shall it interfere in any way with such Participant’s
right or the Company’s right to terminate the employment or consulting
relationship at any time for any reason.

6.    Term of Plan. The Plan shall become effective upon its adoption by the
Board of Directors (the “Effective Date”). It shall continue in effect for a
term of ten (10) years from the later of the Effective Date or the date any
amendment to add shares to the Plan is approved by stockholders of the Company
unless sooner terminated under Section 15 of the Plan.

7.    Term of Option. The term of each Option shall be the term stated in the
Option Agreement; provided that the term shall be no more than ten (10) years
from the date of grant thereof or such shorter term as may be provided in the
Option Agreement and provided further that, in the case of an Incentive Stock
Option granted to a person who at the time of such grant is a Ten Percent
Holder, the term of the Option shall be five (5) years from the date of grant
thereof or such shorter term as may be provided in the Option Agreement.

8.    Option Exercise Price and Consideration.

(a)    Exercise Price. The per Share exercise price for the Shares to be issued
pursuant to exercise of an Option shall be set forth in the Option Agreement and
be no less than 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 is a Ten Percent Holder,
the per Share exercise price shall be no less than 110% of the Fair Market Value
per Share on the date of grant; or

(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)    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.

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(b)    Permissible 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) and may consist entirely of (1)    
cash; (2) check; (3) subject to any requirements of the Applicable Laws,
delivery of Optionee’s promissory note having such recourse, interest, security
and redemption provisions as the Administrator determines to be appropriate; (4)
cancellation of indebtedness; (5) other Shares that have a Fair Market Value on
the date of surrender equal to the aggregate exercise price of the Shares as to
which the Option is exercised, provided that in the case of Shares acquired,
directly or indirectly, from the Company, such Shares must have been owned by
the Optionee for such period as may be required to avoid the Company’s incurring
an adverse accounting charge; (6) if, as of the date of exercise of an Option
the Company then is permitting employees to engage in a “same-day sale” cashless
brokered exercise program involving one or more brokers, through such a program
that complies with the Applicable Laws (including without limitation the
requirements of Regulation T and other applicable regulations promulgated by the
Federal Reserve Board) and that ensures prompt delivery to the Company of the
amount required to pay the exercise price and any applicable withholding taxes;
(7) any combination of the foregoing methods of payment; or (8) such other
consideration and method of payment as determined by the Administrator and to
the extent permitted under Applicable Laws. 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 and the Administrator may, in its sole discretion, refuse to accept a
particular form of consideration at the time of any Option exercise.

9.    Exercise of Option.

(a)    General.

(i)    Exercisability. Any Option granted hereunder shall be exercisable at such
times and under such conditions as determined by the Administrator, consistent
with the term of the Plan and reflected in the Option Agreement, including
vesting requirements and/or performance criteria with respect to the Company
and/or the Optionee.

(ii)    Leave of Absence. The Administrator shall have the discretion to
determine whether and to what extent the vesting of Options shall be tolled
during any unpaid leave of absence; provided, however, that in the absence of
such determination, vesting of Options shall be tolled during any such unpaid
leave (unless otherwise required by the Applicable Laws). In the event of
military leave, vesting shall toll during any unpaid portion of such leave,
provided that, upon a Participant’s returning from military leave (under
conditions that would entitle him or her to protection upon such return under
the Uniform Services Employment and Reemployment Rights Act), he or she shall be
given vesting credit with respect to Options to the same extent as would have
applied had the Participant continued to provide services to the Company
throughout the leave on the same terms as he or she was providing services
immediately prior to such leave.

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(iii)    Minimum Exercise Requirements. An Option may not be exercised for a
fraction of a Share. The Administrator may require that an Option be exercised
as to a minimum number of Shares, provided that such requirement shall not
prevent an Optionee from exercising the full number of Shares as to which the
Option is then exercisable.

(iv)    Procedures for and Results of Exercise. An Option shall be deemed
exercised when written notice of such exercise has been given to the Company in
accordance with the terms of the Option by the person entitled to exercise the
Option and the Company has received full payment for the Shares with respect to
which the Option is exercised. Full payment may, as authorized by the
Administrator, consist of any consideration and method of payment allowable
under Section 8(b) of the Plan, provided that the Administrator may, in its sole
discretion, refuse to accept any form of consideration at the time of any Option
exercise.

Exercise of an Option in any manner shall result in a decrease in the number of
Shares that thereafter may be 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.

(v)    Rights as Stockholder. Until the issuance of the Shares (as evidenced by
the appropriate entry on the books of the Company or of a duly authorized
transfer agent of the Company), no right to vote or receive dividends or any
other rights as a stockholder shall exist with respect to the Optioned Stock,
notwithstanding the exercise of the Option. No adjustment will be made for a
dividend or other right for which the record date is prior to the date the stock
certificate is issued, except as provided in Section 13 of the Plan.

(b)    Termination of Employment or Consulting Relationship. Except as otherwise
set forth in this Section 9(b), the Administrator shall establish and set forth
in the applicable Option Agreement the terms and conditions upon which an Option
shall remain exercisable, if at all, following termination of an Optionee’s
Continuous Service Status, which provisions may be waived or modified by the
Administrator at any time. Unless the Administrator otherwise provides in the
Option Agreement, to the extent that the Optionee is not vested in Optioned
Stock at the date of termination of his or her Continuous Service Status, or if
the Optionee (or other person entitled to exercise the Option) does not exercise
the Option to the extent so entitled within the time specified in the Option
Agreement or below (as applicable), the Option shall terminate and the Optioned
Stock underlying the unexercised portion of the Option shall revert to the Plan.
In no event may any Option be exercised after the expiration of the Option term
as set forth in the Option Agreement (and subject to Section 7).

The following provisions (1) shall apply to the extent an Option Agreement does
not specify the terms and conditions upon which an Option shall terminate upon
termination of an Optionee’s Continuous Service Status, and (2) establish the
minimum post-termination exercise periods that may be set forth in an Option
Agreement:

(i)    Termination other than Upon Disability or Death or for Cause. In the
event of termination of Optionee’s Continuous Service Status other than under
the circumstances set forth in subsections (ii) through (iv) below, such
Optionee may exercise an

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Option until the earlier of (A) three (3) months following such termination or
(B) the expiration of the term of such Option, to the extent the Optionee was
vested in the Optioned Stock as of the date of such termination; provided,
however, that the Administrator may in the Option Agreement specify an
alternative period of time (but not beyond the expiration date of the Option)
following termination of Optionee’s Continuous Service Status during which
Optionee may exercise the Option as to Shares that were vested and exercisable
as of the date of termination of Optionee’s Continuous Service Status. No
termination shall be deemed to occur and this Section 9(b)(i) shall not apply if
(i) the Optionee is a Consultant who becomes an Employee, or (ii) the Optionee
is an Employee who becomes a Consultant.

(ii)    Termination Upon Disability of Optionee. In the event of termination of
an Optionee’s Continuous Service Status as a result of his or her disability
(including a disability within the meaning of Section 22(e)(3) of the Code),
such Optionee may exercise an Option at any time within twelve months following
such termination to the extent the Optionee was vested in the Optioned Stock as
of the date of such termination.

(iii)    Termination Upon Death of Optionee. In the event of the death of an
Optionee during the period of Continuous Service Status since the date of grant
of the Option, or within thirty days following termination of Optionee’s
Continuous Service Status, the Option may be exercised by Optionee’s estate or
by a person who acquired the right to exercise the Option by bequest or
inheritance at any time within twelve months following the date of death, but
only to the extent the Optionee was vested in the Optioned Stock as of the date
of death or, if earlier, the date the Optionee’s Continuous Service Status
terminated.

(iv)    Termination for Cause. Except as otherwise provided in an employment
offer letter, amendment thereto, and/or Award agreement or amendment thereto:
(i) in the event of termination of an Optionee’s Continuous Service Status for
Cause, any Option (including any exercisable portion thereof) held by such
Optionee shall immediately terminate in its entirety upon first notification to
the Optionee of termination of the Optionee’s Continuous Service Status; and
(ii) if an Optionee’s employment or consulting relationship with the Company is
suspended pending an investigation of whether the Optionee shall be terminated
for Cause, all the Optionee’s rights under any Option likewise shall be
suspended during the investigation period and the Optionee shall have no right
to exercise any Option; and (iii) the Administrator shall have authority to
effect such procedures and take such actions as are necessary to carry out the
legal intent of this Section 9(b)(iv), including such procedures and actions as
are required to cause the Optionee to return to the Company Shares purchased
under the Option that have been purchased or that vested within six months of
the events giving rise to the for-Cause termination of the Optionee’s Continuous
Service Status and, if such Shares have been transferred by the Optionee, to
remit to the Company the value of such transferred Shares.

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

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10.    Stock Purchase Rights.

(a)    Rights to Purchase. When the Administrator determines that it will offer
Stock Purchase Rights under the Plan, it shall advise the offeree in writing of
the terms, conditions and restrictions related to the offer, including the
number of Shares that such person shall be entitled to purchase or otherwise
acquire, the price to be paid (including the method of payment) and the time
within which such person must accept such offer. The purchase price of Shares
subject to Stock Purchase Rights shall be as determined by the Administrator.
The consideration shall be as determined by the Administrator consistent with
Section 9(b). The offer to purchase Shares subject to Stock Purchase Rights
shall be accepted by execution of a Restricted Stock Purchase Agreement in the
form determined by the Administrator or in such other manner as determined by
the Administrator as specified in the Restricted Stock Purchase Agreement.

(b)    Repurchase Option.

(i)    General. Unless the Administrator determines otherwise, the Restricted
Stock Purchase Agreement shall grant the Company a repurchase option exercisable
upon the voluntary or involuntary termination of the purchaser’s employment with
the Company for any reason (including death or disability). Subject to any
requirements of the Applicable Laws (including without limitation Section
260.140.8 of the Rules of the California Corporations Commissioner), the terms
of the Company’s repurchase option (including without limitation the price at
which, and the consideration for which, it may be exercised, and the events upon
which it shall lapse) shall be as determined by the Administrator in its sole
discretion and reflected in the Restricted Stock Purchase Agreement.

(ii)    Leave of Absence. The Administrator shall have the discretion to
determine whether and to what extent the lapsing of Company repurchase rights
shall be tolled during any unpaid leave of absence; provided, however, that in
the absence of such determination, such lapsing shall be tolled during any such
unpaid leave (unless otherwise required by the Applicable Laws). In the event of
military leave, the lapsing of Company repurchase rights shall toll during any
unpaid portion of such leave, provided that, upon a Participant’s returning from
military leave (under conditions that would entitle him or her to protection
upon such return under the Uniform Services Employment and Reemployment Rights
Act), he or she shall be given “vesting” credit with respect to Shares purchased
pursuant to the Restricted Stock Purchase Agreement to the same extent as would
have applied had the Participant continued to provide services to the Company
throughout the leave on the same terms as he or she was providing services
immediately prior to such leave.

(iii)    Termination for Cause. Except as otherwise provided in an employment
offer letter, amendment thereto, and/or Award agreement or amendment thereto:
(i) in the event of termination of a Participant’s Continuous Service Status for
Cause, the Company shall have the right to repurchase from the Participant
vested Shares issued upon exercise of a Stock Purchase Right upon the following
terms: (A) the repurchase must be made within 6 months of termination of the
Participant’s Continuous Service Status for Cause at the lower of

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(x) Participant’s original cost for the Shares and (y) the Fair Market Value of
the Shares as of the date of termination, and (B) the repurchase shall be
effected pursuant to such terms and conditions as the Administrator shall
determine are necessary and appropriate to carry out the intent of this Section
10(b)(iii); and (ii) the Administrator shall have authority to effect such
procedures and take such actions as are necessary to carry out the legal intent
of this Section 10(b)(iii), including such procedures and actions as are
required to cause the Participant to return to the Company Shares purchased
under the Stock Purchase Right that have vested within six months of the events
giving rise to the for-Cause termination of the Participant’s Continuous Service
Status and, if such Shares have been transferred by the Participant, to remit to
the Company the value of such transferred Shares. Nothing in this Section
10(b)(iii) shall in any way limit the Company’s right to purchase unvested
Shares as set forth in the applicable Restricted Stock Purchase Agreement.

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

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

11.    Taxes.

(a)    Tax Withholding Obligation.

(i)    As a condition of the grant, vesting or exercise of an Option or Stock
Purchase Right granted under the Plan, the Participant (or in the case of the
Participant’s death, the person exercising the Option or Stock Purchase Right)
shall make such arrangements as the Administrator may require for the
satisfaction of any applicable federal, state, local or foreign withholding tax
obligations that may arise in connection with such grant, vesting or exercise of
the Option or Stock Purchase Right or the issuance of Shares. The Company shall
not be required to issue any Shares under the Plan until such obligations are
satisfied. If the Administrator allows the withholding or surrender of Shares to
satisfy a Participant’s tax withholding obligations under this Section 11, the
Administrator shall not allow Shares to be withheld in an amount that exceeds
the minimum statutory withholding rates for federal and state tax purposes,
including payroll taxes.

(ii)    In the case of an Employee and in the absence of any other arrangement,
the Employee shall be deemed to have directed the Company to withhold or collect
from his or her compensation an amount sufficient to satisfy such tax
obligations from the next

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payroll payment otherwise payable after the date of an exercise of the Option or
Stock Purchase Right.

(iii)    This Section 11(a) shall apply only after the date, if any, upon which
the Common Stock becomes a Listed Security. In the case of Participant other
than an Employee (or in the case of an Employee where the next payroll payment
is not sufficient to satisfy such tax obligations, with respect to any remaining
tax obligations), in the absence of any other arrangement and to the extent
permitted under the Applicable Laws, the Participant shall be deemed to have
elected to have the Company withhold from the Shares to be issued upon exercise
of the Option or Stock Purchase Right that number of Shares having a Fair Market
Value determined as of the applicable Tax Date (as defined below) equal to the
amount required to be withheld. For purposes of this Section 11, 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 under the Applicable Laws (the
“Tax Date”).

(iv)    If permitted by the Administrator, in its discretion, a Participant may
satisfy his or her tax withholding obligations upon exercise of an Option or
Stock Purchase Right by surrendering to the Company Shares that have a Fair
Market Value determined as of the applicable Tax Date equal to the amount
required to be withheld. In the case of shares previously acquired from the
Company that are surrendered under this Section 11(a)(iv), such Shares must have
been owned by the Participant for more than six (6) months on the date of
surrender (or such other period of time as is required for the Company to avoid
adverse accounting charges).

(v)    Any election or deemed election by a Participant to have Shares withheld
to satisfy tax withholding obligations under Section 11(a)(iii) or (iv) above
shall be irrevocable as to the particular Shares as to which the election is
made and shall be subject to the consent or disapproval of the Administrator.
Any election by a Participant under Section 11(a)(iv) above must be made on or
prior to the applicable Tax Date.

(vi)    In the event an election to have Shares withheld is made by a
Participant and the Tax Date is deferred under Section 83 of the Code because no
election is filed under Section 83(b) of the Code, the Participant shall receive
the full number of Shares with respect to which the Option or Stock Purchase
Right is exercised but such Participant shall be unconditionally obligated to
tender back to the Company the proper number of Shares on the Tax Date.

(b)    Compliance with Section 409A. Notwithstanding anything to the contrary
contained in this Plan, to the extent that the Administrator determines that any
Award granted under the Plan is subject to Code Section 409A and unless
otherwise specified in the applicable Award Agreement, the Award Agreement
evidencing such Award shall incorporate the terms and conditions necessary for
such Award to avoid the consequences described in Code Section 409A(a)(1), and
to the maximum extent permitted under Applicable Law (and unless otherwise
stated in the applicable Award Agreement), the Plan and the Award Agreements
shall be interpreted in a manner that results in their conforming to the
requirements of Code Section

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409A(a)(2), (3) and (4) and any Department of Treasury or Internal Revenue
Service regulations or other interpretive guidance issued under Section 409A
(whenever issued, the “Guidance”). Notwithstanding anything to the contrary in
this Plan (and unless the Award Agreement provides otherwise, with specific
reference to this sentence), to the extent that a Participant holding an Award
that constitutes “deferred compensation” under Section 409A and the Guidance is
a “specified employee” (also as defined thereunder), no distribution or payment
of any amount shall be made before a date that is six (6) months following the
date of such Participant’s “separation from service” (as defined in Section 409A
and the Guidance) or, if earlier, the date of the Participant’s death.

(c)    Deferral of Award Benefits. The Administrator may in its discretion and
upon such terms and conditions as it determines appropriate permit one or more
Participants whom it selects to (a) defer compensation payable pursuant to the
terms of an Award, or (b) defer compensation arising outside the terms of this
Plan pursuant to a program that provides for deferred payment in satisfaction of
such other compensation amounts through the issuance of one or more Awards. Any
such deferral arrangement shall be evidenced by an Award Agreement in such form
as the Administrator shall from time to time establish, and no such deferral
arrangement shall be a valid and binding obligation unless evidenced by a fully
executed Award Agreement, the form of which the Administrator has approved,
including through the Administrator’s establishing a written program (the
“Program”) under this Plan to govern the form of Award Agreements participating
in such Program. Any such Award Agreement or Program shall specify the treatment
of dividends or dividend equivalent rights (if any) that apply to Awards
governed thereby, and shall further provide that any elections governing payment
of amounts pursuant to such Program shall be in writing, shall be delivered to
the Company or its agent in a form and manner that complies with Code Section
409A and the Guidance, and shall specify the amount to be distributed in
settlement of the deferral arrangement, as well as the time and form of such
distribution in a manner that complies with Code Section 409A and the Guidance.

12.    Non-Transferability of Options and Stock Purchase Rights.

(a)    General. Except as set forth in this Section 12, Options and Stock
Purchase Rights may not be sold, pledged, assigned, hypothecated, transferred or
disposed of in any manner other than by will or by the laws of descent or
distribution. The designation of a beneficiary by an Optionee will not
constitute a transfer. An Option or Stock Purchase Right may be exercised,
during the lifetime of the holder of an Option or Stock Purchase Right, only by
such holder or a transferee permitted by this Section 12.

(b)    Limited Transferability Rights. Notwithstanding anything else in this
Section 12, the Administrator may in its discretion grant Nonstatutory Stock
Options that may be transferred by instrument to an inter vivos or testamentary
trust in which the Options are to be passed to beneficiaries upon the death of
the trustor (settlor) or by gift or pursuant to domestic relations orders to
“Immediate Family” (as defined below) of the Optionee. “Immediate Family” means
any child, stepchild, grandchild, parent, stepparent, grandparent, spouse,
former spouse, sibling, niece, nephew, mother-in-law, father-in-law, son-in-law,
daughter-in-law, brother-in-law,

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or sister-in-law (including adoptive relationships), a trust in which these
persons have more than fifty percent of the beneficial interest, a foundation in
which these persons (or the Optionee) control the management of assets, and any
other entity in which these persons (or the Optionee) own more than fifty
percent of the voting interests.

13.    Adjustments Upon Changes in Capitalization, Merger or Certain Other
Transactions.

(a)    Changes in Capitalization. Subject to any action required under
Applicable Laws by the stockholders of the Company, the number of Shares of
Common Stock covered by each outstanding award, and the number of Shares of
Common Stock that have been authorized for issuance under the Plan but as to
which no awards have yet been granted or that have been returned to the Plan
upon cancellation or expiration of an award, as well as the price per Share of
Common Stock covered by each such outstanding award, shall be proportionately
adjusted for any increase or decrease in the number of issued Shares of Common
Stock resulting from a stock split, reverse stock split, stock dividend,
combination, recapitalization or reclassification of the Common Stock, or any
other increase or decrease in the number of issued Shares of Common Stock
effected without receipt of consideration by the Company; provided, however,
that conversion of any convertible securities of the Company shall not be deemed
to have been “effected without receipt of consideration.” Such adjustment shall
be made by the Administrator, whose determination in that respect shall be
final, binding and conclusive. Except as expressly provided herein, no issuance
by the Company of shares of stock of any class, or securities convertible into
shares of stock of any class, shall affect, and no adjustment by reason thereof
shall be made with respect to, the number or price of Shares of Common Stock
subject to an award.

(b)    Dissolution or Liquidation. In the event of the dissolution or
liquidation of the Company, each Option and Stock Purchase Right will terminate
immediately prior to the consummation of such action, unless otherwise
determined by the Administrator.

(c)    Corporate Transaction. In the event of a Corporate Transaction (including
without limitation a Change of Control), the Board or Committee may, in its
discretion, (1) provide for the assumption or substitution of, or adjustment to,
each outstanding Option and Stock Purchase Right by the successor corporation or
a parent or subsidiary of the successor corporation (the “Successor
Corporation”); (2) accelerate the vesting and termination of outstanding Options
and Stock Purchase Rights, in whole or in part, so that Options and Stock
Purchase Rights can be exercised before or otherwise in connection with the
closing or completion of the transaction or event but then terminate; and/or (3)
provide for termination of Options and Stock Purchase Rights as a result of the
Corporate Transaction on such terms and conditions as it deems appropriate,
including providing for the cancellation of Options or Stock Purchase Rights for
a cash payment to the Participant. The Board or Committee need not provide for
identical treatment of each outstanding award.

For purposes of this Section 13(c), an Option or a Stock Purchase Right shall be
considered assumed, without limitation, if, at the time of issuance of the stock
or other

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consideration upon a Corporate Transaction or a Change of Control, as the case
may be, each holder of an Option or Stock Purchase Right would be entitled to
receive upon exercise of the award the same number and kind of shares of stock
or the same amount of property, cash or securities as such holder would have
been entitled to receive upon the occurrence of the transaction if the holder
had been, immediately prior to such transaction, the holder of the number of
Shares of Common Stock covered by the award at such time (after giving effect to
any adjustments in the number of Shares covered by the Option or Stock Purchase
Right as provided for in this Section 13); provided that if such consideration
received in the transaction is not solely common stock of the Successor
Corporation, the Administrator may, with the consent of the Successor
Corporation, provide for the consideration to be received upon exercise of the
award to be solely common stock of the Successor Corporation equal to the Fair
Market Value of the per Share consideration received by holders of Common Stock
in the transaction.

(d)    Certain Distributions. In the event of any distribution to the Company’s
stockholders of securities of any other entity or other assets (other than
dividends payable in cash or stock of the Company) without receipt of
consideration by the Company, the Administrator may, in its discretion,
appropriately adjust the price per Share of Common Stock covered by each
outstanding Option or Stock Purchase Right to reflect the effect of such
distribution.

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 other date as is determined by the Administrator, provided that
in the case of any Incentive Stock Option, the grant date shall be the later of
the date on which the Administrator makes the determination granting such
Incentive Stock Option or the date of commencement of the Optionee’s employment
relationship with the Company. Notice of the determination shall be given to
each Employee or Consultant 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)    Authority to Amend or Terminate. The Board may at any time amend, alter,
suspend or discontinue the Plan, but no amendment, alteration, suspension or
discontinuation (other than an adjustment pursuant to Section 13 above) shall be
made that would materially and adversely affect the rights of any Optionee or
holder of Stock Purchase Rights under any outstanding grant, without his or her
consent. In addition, to the extent necessary and desirable to comply with the
Applicable Laws, the Company shall obtain stockholder approval of any Plan
amendment in such a manner and to such a degree as required.

(b)    Effect of Amendment or Termination. Except as to amendments which the
Administrator has the authority under the Plan to make unilaterally, no
amendment or termination of the Plan shall materially and adversely affect
Options or Stock Purchase Rights already granted, unless mutually agreed
otherwise between the Optionee or holder of the Stock Purchase Rights and the
Administrator, which agreement must be in writing and signed by the Optionee or
holder and the Company.

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16.    Conditions Upon Issuance of Shares. Notwithstanding any other provision
of the Plan or any agreement entered into by the Company pursuant to the Plan,
the Company shall not be obligated to issue or deliver any Shares under the Plan
unless such issuance or delivery would comply with the Applicable Laws, with
such compliance determined by the Company in consultation with its legal
counsel. As a condition to the exercise of an Option or Stock Purchase Right,
the Company may require the person exercising the award 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
by law. Shares issued upon exercise of awards granted prior to the date on which
the Common Stock becomes a Listed Security shall be subject to a right of first
refusal in favor of the Company pursuant to which the Participant will be
required to offer Shares to the Company before selling or transferring them to
any third party on such terms and subject to such conditions as are reflected in
the applicable Option Agreement or Restricted Stock Purchase Agreement. In
addition, awards issued prior to the date on which the Common Stock becomes a
Listed Security shall require the Participant to agree to a lock-up agreement in
connection with public offerings of the Company’s stock that applies to all
capital stock and rights to purchase capital stock of the Company held by the
Participant on such terms and subject to such conditions as are reflected in the
applicable Option Agreement or Restricted Stock Purchase Agreement.

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

18.    Agreements. Options and Stock Purchase Rights shall be evidenced by
Option Agreements and Restricted Stock Purchase Agreements, respectively, in
such form(s) as the Administrator shall from time to time approve.

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

20.    Information and Documents to Optionees and Purchasers. Prior to the date,
if any, upon which the Common Stock becomes a Listed Security and if required by
the Applicable Laws, the Company shall provide financial statements at least
annually to each Optionee and to each individual who acquired Shares pursuant to
the Plan, during the period such Optionee or purchaser has one or more Options
or Stock Purchase Rights outstanding, and in the case of an individual who
acquired Shares pursuant to the Plan, during the period such individual owns
such Shares. Except as required by Applicable Law, the Company shall not be
required to provide such information if the issuance of Options or Stock
Purchase Rights under the Plan is limited to key persons whose duties in
connection with the Company assure their access to equivalent information.

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21.    Notice. Any written notice to the Company required by any provisions of
this Plan shall be addressed to the Secretary of the Company and shall be
effective when received.

22.    Governing Law; Interpretation of Plan and Awards.

(a)    This Plan and all determinations made and actions taken pursuant hereto
shall be governed by the substantive laws, but not the choice of law rules, of
the state of California.

(b)    In the event that any provision of the Plan or any Award granted under
the Plan is declared to be illegal, invalid or otherwise unenforceable by a
court of competent jurisdiction, such provision shall be reformed, if possible,
to the extent necessary to render it legal, valid and enforceable, or otherwise
deleted, and the remainder of the terms of the Plan and/or Award shall not be
affected except to the extent necessary to reform or delete such illegal,
invalid or unenforceable provision.

(c)    The headings preceding the text of the sections hereof are inserted
solely for convenience of reference, and shall not constitute a part of the
Plan, nor shall they affect its meaning, construction or effect.

(d)    The terms of the Plan and any Award shall inure to the benefit of and be
binding upon the parties hereto and their respective permitted heirs,
beneficiaries, successors and assigns.

(e)    All questions arising under the Plan or under any Award shall be decided
by the Administrator in its total and absolute discretion. In the event the
Participant believes that a decision by the Administrator with respect to such
person was arbitrary or capricious, the Participant may request arbitration with
respect to such decision. The review by the arbitrator shall be limited to
determining whether the Administrator’s decision was arbitrary or capricious.
This arbitration shall be the sole and exclusive review permitted of the
Administrator’s decision, and the Awardee shall as a condition to the receipt of
an Award be deemed to explicitly waive any right to judicial review.

(f)    Reserved.

23.    Limitation on Liability. The Company and any Affiliate which is in
existence or hereafter comes into existence shall not be liable to a
Participant, an Employee or any other persons as to:

(a)    The Non-Issuance of Shares. The non-issuance or sale of Shares (including
under Section 16 above) as to which the Company has been unable to obtain from
any regulatory body having jurisdiction the authority deemed by the Company’s
counsel to be necessary to the lawful issuance and sale of any shares hereunder.

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(b)    Tax Consequences. Any tax consequence realized by any Participant,
Employee or other person due to the receipt, vesting, exercise or settlement of
any Option or other Award granted hereunder or due to the transfer of any Shares
issued hereunder. The Participant is responsible for, and by accepting an Award
under the Plan agrees to bear, all taxes of any nature that are legally imposed
upon the Participant in connection with an Award, and the Company does not
assume, and will not be liable to any party for, any cost or liability arising
in connection with such tax liability legally imposed on the Participant. In
particular, Awards issued under the Plan may be characterized by the Internal
Revenue Service (the “IRS”) as “deferred compensation” under the Code resulting
in additional taxes, including in some cases interest and penalties. In the
event the IRS determines that an Award constitutes deferred compensation under
the Code or challenges any good faith characterization made by the Company or
any other party of the tax treatment applicable to an Award, the Participant
will be responsible for the additional taxes, and interest and penalties, if
any, that are determined to apply if such challenge succeeds, and the Company
will not reimburse the Participant for the amount of any additional taxes,
penalties or interest that result.

(c)    Forfeiture. The requirement that Participant forfeit an Award, or the
benefits received or to be received under an Award, pursuant to any Applicable
Law.