Exhibit 10.2

ATTACHMENT A

A10 NETWORKS, INC.
2008 Stock Plan
STOCK OPTION AGREEMENT

A10 Networks, Inc. (the "Company") hereby grants an option (the “Option”) to
purchase shares of its Common Stock (“Shares”) to the optionee named below on
the terms and conditions set forth in this cover sheet, the Company’s 2008 Stock
Plan, and all exhibits attached hereto (together, the “Stock Option Agreement"):

Grant Number:
«Grant_No»
 
Date of Grant
«Grant_Date»
 
Vesting Commencement Date
«VCD»
 
Exercise Price Per Share
US$«Price»
 
Total Number of Shares Granted
«Shares»
 
Type of Option
x Incentive Stock Option
 
 
__ Nonqualified Stock Option
 
Expiration Date
«Term_Date»
 

Exercise and Vesting Schedule:

The Option granted hereunder may be exercised, in whole or in part, based on the
vesting schedule as set forth below.

[INSERT VESTING SCHEDULE]

By signing this cover sheet, you agree that this Stock Option Agreement is
subject to the terms and conditions of this cover sheet, the 2008 Stock Plan and
Exhibits A-C, which are attached hereto and made a part of this document.

OPTIONEE:
 
A10 NETWORKS, INC.
 
 
 
a California corporation
 
 
 
/s/ Greg Straughn
 
«First» «Last»

 
Greg Straughn, CFO
 

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EXHIBIT A

STOCK OPTION AGREEMENT

Type of Option

The type of option which you have been granted is designated on the cover sheet.
If designated as an Incentive Stock Option, the Option is intended to be an
incentive stock option under section 422 of the United States Internal Revenue
Code (the "Code") and will be interpreted accordingly.

Capitalized terms used but not otherwise defined in this Stock Option Agreement
shall have the meanings given to them in the Plan.

Vesting

You may exercise the Option during its term in accordance with the exercise
schedule set out in the cover sheet and the applicable provisions of the Plan
and this Stock Option Agreement. In the event of your death, Disability or other
termination of status as a Service Provider, the exercisability of the option is
governed by the applicable provisions of the Plan and this Stock Option
Agreement.

Term
    
The Option may be exercised only within the term set out in the cover sheet, and
may be exercised during such term only in accordance with the Plan and this
Stock Option Agreement. Notwithstanding any post-termination exercise period set
forth in this Stock Option Agreement, the Option will expire on the Expiration
Date shown on the cover sheet, which is the day before the 10th anniversary of
the Date of Grant. It may expire earlier if your status as a Service Provider
terminates, as described below.

Regular Termination

In the event of the termination of your status as a Service Provider for any
reason other than death or Disability, you may, to the extent otherwise so
entitled at the date of such termination, exercise the Option within 90 days
after your termination. To the extent that you were not entitled to exercise the
Option at the date of such termination, or if you do not exercise the Option
within the 90-day period specified above, the Option will terminate.

Death

If your status as Service Provider terminates because of your death, the Option
may be exercised at any time within twelve (12) months following the date of
death by your estate or by a person who acquired the right to exercise the
Option by bequest or inheritance, but only to the extent that the Option was
exercisable as of the date of your death.

Disability

If your status as Service Provider terminates because of your Disability, you
may, but only within six (6) months from the date of such termination, exercise
the Option to the extent that the Option was exercisable as of the date of such
termination.

Status as Service Provider

For purposes of the Option, your status as a Service Provider will be considered
terminated for purposes of vesting and any post-termination exercise period as
of the date you are no longer actively providing services to the Company or a
Parent or Subsidiary (regardless of the reason for such termination and whether
or not later found to be invalid or in breach of employment laws in the
jurisdiction where you are employed or the terms of your employment agreement,

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if any) and will not be extended by any notice period (e.g., your period of
service would not include any contractual notice period or any period of “garden
leave” or similar period mandated under employment laws in the jurisdiction
where you are employed or the terms of your employment agreement, if any); the
Administrator shall have the exclusive discretion to determine when you are no
longer actively providing services for purposes of the Option (including whether
you may still be considered to be providing services while on a leave of
absence).

Further, no claim or entitlement to compensation or damages shall arise from
forfeiture of the Option resulting from the termination of your status as a
Service Provider (for any reason whatsoever, whether or not later found to be
invalid or in breach of employment laws in the jurisdiction where you are
employed or the terms of your employment agreement, if any), and in
consideration of the grant of the Option to which you are otherwise not
entitled, you irrevocably agree never to institute any claim against the Company
or any Parent or Subsidiary, waive your ability, if any, to bring any such
claim, and release the Company and any Parent or Subsidiary from any such claim;
if, notwithstanding the foregoing, any such claim is allowed by a court of
competent jurisdiction, then, by participating in the Plan, you shall be deemed
irrevocably to have agreed not to pursue such claim and agree to execute any and
all documents necessary to request dismissal or withdrawal of such claim.

Restrictions on Exercise

The Company will not permit you to exercise the Option if the issuance of Shares
at that time would violate any applicable law or regulation. Further,
notwithstanding any other provision of the Plan or this Stock Option Agreement,
unless there is an available exemption from any registration, qualification or
other legal requirement applicable to the Shares, the Company shall not be
required to deliver any Shares issuable upon exercise of the Option prior to the
completion of any registration or qualification of the Shares under any local,
state, federal or foreign securities or exchange control law or under rulings or
regulations of the United States Securities and Exchange Commission (“SEC”) or
of any other governmental regulatory body, or prior to obtaining any approval or
other clearance from any local, state, federal or foreign governmental agency,
which registration, qualification or approval the Company shall, in its absolute
discretion, deem necessary or advisable. You understand that the Company is
under no obligation to register or qualify the Shares with the SEC or any state
or foreign securities commission or to seek approval or clearance from any
governmental authority for the issuance or sale of the shares. Further, you
agree that the Company shall have unilateral authority to amend the Plan and
this Stock Option Agreement without your consent to the extent necessary to
comply with securities or other laws applicable to issuance of Shares.

Notice of Exercise

When you wish to exercise the Option, you must notify the Company by filing the
proper "Notice of Exercise" form (attached hereto as Exhibit C) at the address
given on the form. Your notice must specify how many Shares you wish to
purchase. The notice will be effective when it is received by the Company. If
someone else wants to exercise the Option after your death, that person must
prove to the Company's satisfaction that he or she is entitled to do so.

Form of Payment

Your Notice of Exercise must be accompanied by payment of the aggregate purchase
price plus any applicable Tax-Related Items (as defined below) as to all Shares
you wish to purchase. Payment of the purchase price and any applicable
Tax-Related Items shall be by cash or personal check.

Tax Withholding

You acknowledge that, regardless of any action taken by the Company or, if
different, your employer (the “Employer”) the ultimate liability for all income
tax, social insurance, payroll tax, fringe benefits tax, payment on account or
other tax‑related items related to your participation in the Plan and legally
applicable to you (“Tax-Related Items”), is and remains your responsibility and
may exceed the amount actually withheld by the Company or the Employer. You
further acknowledge that the Company and/or the Employer (i) make no
representations or undertakings regarding the treatment of any Tax-Related Items
in connection with any aspect of the Option, including, but not limited to, the
grant, vesting or exercise of the Option, the subsequent sale of Shares acquired
pursuant to such exercise and the receipt of

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any dividends; and (ii) do not commit to and are under no obligation to
structure the terms of the grant or any aspect of the Option to reduce or
eliminate your liability for Tax-Related Items or achieve any particular tax
result.

Prior to the relevant taxable or tax withholding event, as applicable, you agree
to make adequate arrangements satisfactory to the Company and/or the Employer to
satisfy all Tax-Related Items. If you fail to make satisfactory arrangements for
the payment of any required Tax-Related Items hereunder at the time of the
Option exercise, you acknowledge and agree that the Company may refuse to honor
the exercise and refuse to deliver the Shares if such amounts are not delivered
at the time of exercise together with the purchase price.
To the extent determined appropriate by the Company in its discretion, the
Company shall have the right (but not the obligation) to satisfy any Tax-Related
Items by withholding from any cash compensation due to you and/or reducing the
number of Shares otherwise deliverable to you upon exercise of the Option.
Further, if you are subject to Tax-Related Items in more than one jurisdiction
between the Date of Grant and the date of any relevant taxable or tax
withholding event, as applicable, you acknowledge that the Company and/or the
Employer (or former employer, as applicable) may be required to withhold or
account for Tax-Related Items in more than one jurisdiction.
No Advice Regarding Participation

The Company is not providing any tax, legal or financial advice, nor is the
Company making any recommendations regarding your participation in the Plan, the
exercise of the Option or the sale of any Shares acquired upon exercise of the
Option. You are hereby advised to consult with your own personal tax, legal and
financial advisors regarding your participation in the Plan before taking any
action related to the Plan.

Representations

If the Shares you intend to purchase have not been registered under the United
States Securities Act of 1933, as amended, at the time the Option is exercised,
the Company may require you to (i) deliver to the Company your Investment
Representation Statement (attached as Exhibit B), which may contain, among other
things, an agreement to refrain from sales of the Shares for up to 180 days
immediately following an underwritten initial public offering, and (ii) read the
applicable rules of the Commissioner of Corporations of California attached to
such Investment Representation Statement, if applicable.

Right of First Refusal

In the event that you propose to sell, pledge or otherwise transfer to a third
party any Shares acquired under this Stock Option Agreement, or any interest in
such Shares, the Company shall have the "Right of First Refusal" with respect to
all (and not less than all) of such Shares. If you desire to transfer any Shares
acquired under this Stock Option Agreement, you must give a written notice to
the Company describing fully the proposed transfer, including the number of
Shares proposed to be transferred, the proposed transfer price and the name and
address of the proposed transferee. The Company shall have the right to purchase
all, and not less than all, of the Shares on the terms of the proposal described
in the notice by delivery of a notice of exercise of the Right of First Refusal
within 30 days after the date when the notice was received by the Company.

If the Company fails to exercise its Right of First Refusal within 30 days after
the date when it received the notice, you may, not later than three (3) months
following receipt of the notice by the Company, conclude a transfer of the
Shares on the terms and conditions described in the notice. If the Company
exercises its Right of First Refusal, the parties shall consummate the sale of
the Shares within 30 days after the date when the Company received the notice.
The Company's Right of First Refusal shall terminate in the event that Stock is
listed on an established stock exchange or is quoted regularly on the Nasdaq
National Market.

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Transfer of Option

Prior to your death, only you may exercise the Option. You cannot transfer or
assign the Option. For instance, you may not sell the Option or use it as
security for a loan. If you attempt to transfer or assign the Option, the Option
will immediately become invalid. You may, however, dispose of the Option in your
will.

Regardless of any marital property settlement agreement, the Company is not
obligated to honor a notice of exercise from your spouse or former spouse, nor
is the Company obligated to recognize such individual's interest in the Option
in any other way.

No Employment Rights

Neither the Option grant, this Stock Option Agreement or your participation in
the Plan shall create a right to employment or be interpreted as forming an
employment or service contract with the Company, the Employer or any Parent or
Subsidiary, and shall not interfere with the ability of the Company, the
Employer or any Parent or Subsidiary, as applicable, to terminate your
employment or service relationship (if any) at any time and for any reason.
Nature of Grant

In accepting the Option, you acknowledge, understand and agree that: (1) the
Plan is established voluntarily by the Company, it is discretionary in nature,
and may be amended, suspended or terminated by the Company at any time to the
extent permitted by the Plan; (2) the grant of the Option is voluntary and
occasional and does not create any contractual or other right to receive future
grants of options, or benefits in lieu of options, even if options have been
granted in the past; (3) all decisions with respect to future option or other
grants, if any, will be at the sole discretion of the Company; (4) you are
voluntarily participating in the Plan; (5) the Option and any Shares acquired
under the Plan are not intended to replace any pension rights or compensation;
(5) the Option and any Shares acquired under the Plan and the income and value
of same, are not part of normal or expected compensation for any purpose; (6)
the future value of the Shares underlying the Option is unknown, indeterminable,
and cannot be predicted with certainty; (7) if the underlying Shares do not
increase in value, the Option will have no value; (8) if you exercise the Option
and acquire Shares, the value of such Shares may increase or decrease in value,
even below the exercise price; (9) unless otherwise provided in the Plan or this
Stock Option Agreement, or by the Company in its discretion, the Option and the
benefits evidenced by this Stock Option Agreement do not create any entitlement
to have the Option or any such benefits transferred to, or assumed by, another
company nor to be exchanged, cashed out or substituted for, in connection with
any corporate transaction affecting the Shares of the Company; and (10) neither
the Company, the Employer nor any Parent or Subsidiary shall be liable for any
foreign exchange rate fluctuation between your local currency and the United
States Dollar that may affect the value of the Option or of any amounts due to
you pursuant to the exercise of the Option or the subsequent sale of any Shares
acquired upon exercise.
Shareholder Rights

Neither you, your estate nor your heirs, shall have any rights as a shareholder
of the Company until a certificate for your option Shares has been issued. No
adjustments are made for dividends or other rights if the applicable record date
occurs before your stock certificate is issued, except as described in the Plan.

Adjustments

In the event of a stock split, a stock dividend or a similar change in the
Company stock, the number of Shares covered by the Option and the exercise price
per share may be adjusted pursuant to the Plan. In the event of the proposed
dissolution or liquidation of the Company, or of a merger in which the successor
corporation does not agree to assume the Option or substitute an equivalent
option, the Board shall notify you at least thirty (30) days prior to such
proposed action. To the extent it has not been previously exercised, the Option
will terminate immediately prior to the consummation of such proposed action.

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Legends

All certificates representing the Shares issued upon exercise of this Option
shall, where applicable, have endorsed thereon the following legends:

"THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN RESTRICTIONS
ON TRANSFER AND OPTIONS TO PURCHASE SUCH SHARES SET FORTH IN AN AGREEMENT
BETWEEN THE COMPANY AND THE REGISTERED HOLDER, OR HIS OR HER PREDECESSOR IN
INTEREST. A COPY OF SUCH AGREEMENT IS ON FILE AT THE PRINCIPAL OFFICE OF THE
COMPANY AND WILL BE FURNISHED UPON WRITTEN REQUEST TO THE SECRETARY OF THE
COMPANY BY THE HOLDER OF RECORD OF THE SHARES REPRESENTED BY THIS CERTIFICATE."

"THE SHARES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE UNITED STATES
SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED, OR OTHERWISE
TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT OR AN
OPINION OF COUNSEL, SATISFACTORY TO THE COMPANY AND ITS COUNSEL, THAT SUCH
REGISTRATION IS NOT REQUIRED."

Governing Law; Venue

This Stock Option Agreement will be interpreted and enforced under the laws of
the State of California without regard to its conflict of law provisions. For
purposes of any action, lawsuit or other proceedings brought to enforce this
Stock Option Agreement, relating to it, or arising from it, the parties hereby
submit to and consent to the sole and exclusive jurisdiction of the courts of
Santa Clara, California or the federal courts for the United States for the
Northern District of California, and no other courts, where this grant is made
and/or to be performed.

Data Privacy

You hereby explicitly and unambiguously consent to the collection, use and
transfer, in electronic or other form, of your personal data as described in
this Stock Option Agreement and any other Option grant materials by and among,
as applicable, the Employer, the Company and any Parent or Subsidiary for the
exclusive purpose of implementing, administering and managing your participation
in the Plan.
You understand that the Company and the Employer may hold certain personal
information about you, including, but not limited to, your name, home address
and telephone number, date of birth, social insurance number or other
identification number, salary, nationality, job title, any Shares or
directorships held in the Company, and details of all options or any other
entitlement to Shares awarded, canceled, exercised, vested, unvested or
outstanding in your favor (“Data”), for the exclusive purpose of implementing,
administering and managing the Plan.

You understand that Data may be transferred to a broker or stock plan service
provider selected by the Company either now or in the future for purposes of
assisting the Company with the implementation, administration and management of
the Plan. You understand that the recipients of the Data may be located in the
United States or elsewhere, and that the recipient’s country (e.g., the United
States) may have different data privacy laws and protections than your country.
You may request a list with the names and addresses of any potential recipients
of the Data by contacting your local human resources representative.

You authorize the Company, the Company’s designated broker or stock plan service
provider and any other possible recipients which may assist the Company
(presently or in the future) with implementing, administering and managing the
Plan to receive, possess, use, retain and transfer the Data, in electronic or
other form, for the sole purposes of implementing, administering and managing
your participation in the Plan. You understand that Data will be held only as
long as is necessary to implement, administer and manage your participation in
the Plan. You understand that you may, at any time, view Data, request
additional information about the storage and processing of Data, require any
necessary amendments to Data or refuse or withdraw the consents herein, in any
case without cost, by contacting in

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writing your local human resources representative. Further, you understand that
you are providing the consents herein on a purely voluntary basis. If you do not
consent, or if you later seek to revoke your consent, your employment status or
service and career with the Employer will not be adversely affected; the only
adverse consequence of refusing or withdrawing your consent is that the Company
would not be able to grant you options or other equity awards or administer or
maintain such awards. Therefore, you understand that refusing or withdrawing
your consent may affect your ability to participate in the Plan. For more
information on the consequences of your refusal to consent or withdrawal of
consent, you understand that you may contact your local human resources
representative.

Electronic Delivery and Acceptance
The Company may, in its sole discretion, decide to deliver any documents related
to your current or future participation in the Plan by electronic means. You
hereby consent to receive such documents by electronic delivery and agree to
participate in the Plan through an on-line or electronic system established and
maintained by the Company or a third party designated by the Company.
Severability
The provisions of this Stock Option Agreement are severable and if any one or
more provisions are determined to be illegal or otherwise unenforceable, in
whole or in part, the remaining provisions shall nevertheless be binding and
enforceable.
Imposition of Other Requirements
The Company reserves the right to impose other requirements on your
participation in the Plan, on the Option and on any Shares purchased upon
exercise of the Option, to the extent the Company determines it is necessary or
advisable for legal or administrative reasons, and to require you to sign any
additional agreements or undertakings that may be necessary to accomplish the
foregoing.
Waiver
You acknowledge that a waiver by the Company of breach of any provision of this
Stock Option Agreement shall not operate or be construed as a waiver of any
other provision of this Stock Option Agreement, or of any subsequent breach by
you or any other optionee.
The Plan and Other Agreements

The text of the Plan is incorporated into this Stock Option Agreement by
reference. This Stock Option Agreement (along with all exhibits and attachments)
and the Plan constitute the entire understanding between you and the Company
regarding this Option. Any prior agreements, commitments or negotiations
concerning this Option are superseded.

By signing the cover sheet of this Stock Option Agreement, you agree to all of
the terms and conditions described in the Stock Option Agreement, including any
exhibits or attachments hereto, and in the Plan.

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EXHIBIT B

INVESTMENT REPRESENTATION STATEMENT

OPTIONEE:
«First» «Last»
 
OPTIONEE:
A10 NETWORKS, INC.
 
OPTIONEE
COMMON STOCK
 
AMOUNT:

 
 
DATE:

 
 

In connection with the purchase of the above-listed Securities, the undersigned
Optionee represents to the Company the following:

(a)    Optionee is aware of the Company's business affairs and financial
condition and has acquired sufficient information about the Company to reach an
informed and knowledgeable decision to acquire the securities. Optionee is
acquiring these securities for investment for Optionee's own account only and
not with a view to, or for resale in connection with, any "distribution" thereof
within the meaning of the United States Securities Act of 1933, as amended (the
"Securities Act").

(b)    Optionee acknowledges and understands that the securities constitute
"restricted securities" under the Securities Act and have not been registered
under the Securities Act in reliance upon a specific exemption therefrom, which
exemption depends upon, among other things, the bona fide nature of Optionee's
investment intent as expressed herein. In this connection, Optionee understands
that, in the view of the United States Securities and Exchange Commission (the
“SEC”), the statutory basis for such exemption may be unavailable if Optionee's
representation was predicated solely upon a present intention to hold these
Securities for the minimum capital gains period specified under tax statutes,
for a deferred sale, for or until an increase or decrease in the market price of
the Securities, or for a period of one year or any other fixed period in the
future. Optionee further understands that the Securities must be held
indefinitely unless they are subsequently registered under the Securities Act or
an exemption from such registration is available. Optionee further acknowledges
and understands that the Company is under no obligation to register the
securities. Optionee understands that the certificate evidencing the securities
will be imprinted with a legend which prohibits the transfer of the Securities
unless they are registered or such registration is not required in the opinion
of counsel satisfactory to the Company, a legend prohibiting their transfer
without the consent of the Commissioner of Corporations of the State of
California and any other legend required under applicable state securities laws.

(c)    Optionee is familiar with the provisions of Rule 701 and Rule 144, each
promulgated under the Securities Act, which, in substance, permit limited public
resale of "restricted securities" acquired, directly or indirectly from the
issuer thereof, in a non-public offering subject to the satisfaction of certain
conditions. Rule 701 provides that if the issuer qualifies under Rule 701 at the
time of exercise of the Option by the Optionee, such exercise will be exempt
from registration under the Securities Act. In the event the Company later
becomes subject to the reporting requirements of Section 13 or 15(d) of the
Securities Exchange Act of 1934 (the “Exchange Act”), ninety (90) days
thereafter the securities exempt under Rule 701 may be resold, subject to the
satisfaction of certain of the conditions specified by Rule 144, including among
other things: (1) the sale being made through a broker in an unsolicited
"broker's transaction" or in transactions directly with a market maker (as said
term is defined under the Exchange Act); and, in the case of an affiliate,
(2) the availability of certain public information about the Company, and the
amount of securities being sold during any three month period not exceeding the
limitations specified in Rule 144(e), if applicable.

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In the event that the Company does not qualify under Rule 701 at the time of
exercise of the Option, then the securities may be resold in certain limited
circumstances subject to the provisions of Rule 144, which requires among other
things: (1) the resale occurring not less than one year after the party has
purchased, and made full payment for, within the meaning of Rule 144, the
securities to be sold; and, in the case of an affiliate, or of a non-affiliate
who has held the securities less than two years, (2) the availability of certain
public information about the Company, (3) the sale being made through a broker
in an unsolicited "broker's transaction" or in transactions directly with a
market maker (as said term is defined under the Exchange Act), and (4) the
amount of securities being sold during any three month period not exceeding the
specified limitations stated therein, if applicable.

(d) Optionee agrees, in connection with the Company's initial underwritten
public offering of the Company's securities, (1) not to sell, make short sale
of, loan, grant any options for the purchase of, or otherwise dispose of any
shares of Common Stock of the Company held by Optionee (other than those shares
included in the registration) without the prior written consent of the Company
or the underwriters managing such initial underwritten public offering of the
Company's securities for one hundred eighty (180) days from the effective date
of such registration, and (2) further agrees to execute any agreement reflecting
(1) above as may be requested by the underwriters at the time of the public
offering; provided however that the officers and directors of the Company who
own stock in the Company also agree to such restrictions.

(e)    Optionee further understands that in the event all of the applicable
requirements of Rule 701 or 144 are not satisfied, registration under the
Securities Act, compliance with Regulation A of the Securities Act, or some
other registration exemption will be required; and that, notwithstanding the
fact that Rules 144 and 701 are not exclusive, the Staff of the SEC has
expressed its opinion that persons proposing to sell private placement
securities other than in a registered offering and otherwise than pursuant to
Rules 144 or 701 will have a substantial burden of proof in establishing that an
exemption from registration is available for such offers or sales, and that such
persons and their respective brokers who participate in such transactions do so
at their own risk. Optionee understands that no assurances can be given that any
such other registration exemption will be available in such event.

(f)    Optionee understands that the certificate evidencing the Securities will
be imprinted with a legend which prohibits the transfer of the Securities
without the consent of the Commissioner of Corporations of California. Optionee
has read the applicable Commissioner's Rules with respect to such restriction, a
copy of which is attached.

 
 
Signature of Optionee
 
 
 
 
 
 
 
Date:
 

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EXHIBIT C

NOTICE OF EXERCISE

A10 NETWORKS, INC.
3 West Plumeria Drive
San Jose, CA 95134
Attention: Chief Financial Officer

1.    Exercise of Option. Effective as of today, ___________, 20__, the
undersigned ("Optionee") hereby elects to exercise Optionee's option to purchase
_________ shares of Common Stock (the "Shares") of A10 NETWORKS, Inc. (the
"Company") under and pursuant to the 2008 Stock Plan (the "Plan") and the Stock
Option Agreement dated «Grant_Date» (the "Option Agreement").

2.    Representations of Optionee. Optionee acknowledges that Optionee has
received, read and understood the Plan and the Option Agreement, including all
exhibits attached thereto, and agrees to abide by and be bound by their terms
and conditions.

3.    Rights as Shareholder. Until the stock certificate evidencing such Shares
is issued (as evidenced by the appropriate entry on the books of the Company or
of a duly authorized transfer agent of the Company), no right to vote or receive
dividends or any other rights as a shareholder shall exist with respect to the
optioned Shares, notwithstanding the exercise of the Option. The Company shall
issue (or cause to be issued) such stock certificate promptly after the Option
is exercised. No adjustment will be made for a dividend or other right for which
the record date is prior to the date the stock certificate is issued, except as
provided in Section 12 of the Plan. Thereafter, Optionee shall enjoy rights as a
shareholder until such time as Optionee disposes of the Shares.

4.    Company's Right of First Refusal. Optionee understands and acknowledges
that the Shares are subject to certain right of first refusal provisions under
the terms of the Plan and Option Agreement.

5.    Tax Consultation. Optionee understands that Optionee may suffer adverse
tax consequences as a result of Optionee's purchase or disposition of the
Shares. Optionee represents that Optionee has consulted with any tax consultants
Optionee deems advisable in connection with the purchase or disposition of the
Shares and that Optionee is not relying on the Company for any tax advice.

6.    Restrictive Legends and Stop‑Transfer Orders.

(A)    Legends. Optionee understands and agrees that the Company shall cause the
legends set forth below or legends substantially equivalent thereto, to be
placed upon any certificate(s) evidencing ownership of the Shares together with
any other legends that may be required by state or federal securities laws:

THE SHARES EVIDENCED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR INVESTMENT AND
HAVE NOT BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS
AMENDED. SUCH SHARES MAY NOT BE SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH
REGISTRATION OR AN EXEMPTION THEREFROM UNDER SAID ACT. COPIES OF THE AGREEMENT
COVERING THE PURCHASE OF THESE SHARES AND RESTRICTING THEIR TRANSFER MAY BE
OBTAINED AT NO COST BY WRITTEN REQUEST MADE BY THE HOLDER OF RECORD OF THIS
CERTIFICATE TO THE SECRETARY OF THE CORPORATION AT THE PRINCIPAL EXECUTIVE
OFFICES OF THE CORPORATION.

"THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN RESTRICTIONS
ON TRANSFER AND OPTIONS TO PURCHASE SUCH SHARES SET FORTH IN AN AGREEMENT
BETWEEN THE COMPANY AND THE REGISTERED HOLDER, OR HIS OR HER PREDECESSOR IN
INTEREST. A COPY OF SUCH AGREEMENT IS ON FILE AT THE PRINCIPAL OFFICE OF THE
COMPANY AND WILL BE

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FURNISHED UPON WRITTEN REQUEST TO THE SECRETARY OF THE COMPANY BY THE HOLDER OF
RECORD OF THE SHARES REPRESENTED BY THIS CERTIFICATE."

(B)    Stop‑Transfer Notices. Optionee agrees that, in order to ensure
compliance with the restrictions referred to herein, the Company may issue
appropriate "stop transfer" instructions to its transfer agent, if any, and
that, if the Company transfers its own securities, it may make appropriate
notations to the same effect in its own records.

(C)    Refusal to Transfer. The Company shall not be required (i) to transfer on
its books any Shares that have been sold or otherwise transferred in violation
of any of the provisions of this Agreement or (ii) to treat as owner of such
Shares or to accord the right to vote or pay dividends to any purchaser or other
transferee to whom such Shares shall have been so transferred.

7.    Successors and Assigns. The Company may assign any of its rights under
this Agreement to single or multiple assignees, and this Agreement shall inure
to the benefit of the successors and assigns of the Company. Subject to the
restrictions on transfer herein set forth, this Agreement shall be binding upon
Optionee and his or her heirs, executors, administrators, successors and
assigns.

8.    Interpretation. Any dispute regarding the interpretation of this Agreement
shall be submitted by Optionee or by the Company forthwith to the Company's
Board of Directors or the committee thereof that administers the Plan, which
shall review such dispute at its next regular meeting. The resolution of such a
dispute by the Board or committee shall be final and binding on the Company and
on Optionee.

9.    Governing Law; Severability. This Agreement shall be governed by and
construed in accordance with the laws of the State of California excluding that
body of law pertaining to conflicts of law. Should any provision of this
Agreement be determined by a court of law to be illegal or unenforceable, the
other provisions shall nevertheless remain effective and shall remain
enforceable.

10.    Notices. Any notice required or permitted hereunder shall be given in
writing and shall be deemed effectively given upon personal delivery or upon
deposit in the United States mail by certified mail, with postage and fees
prepaid, addressed to the other party at its address as shown below beneath its
signature, or to such other address as such party may designate in writing from
time to time to the other party.

11.    Further Instruments. The parties agree to execute such further
instruments and to take such further action as may be reasonably necessary to
carry out the purposes and intent of this Agreement.

12.    Delivery of Payment. Optionee herewith delivers to the Company the full
Exercise Price for the Shares plus any applicable Tax-Related Items (as
described in Exhibit A).

13.    Entire Agreement. The Plan and Notice of Grant/Option Agreement are
incorporated herein by reference. This Notice, the Plan, the Option Agreement
(along with all other exhibits and attachments to the Option Agreement that are
executed and delivered along with this Notice, if any) and the Investment
Representation Statement constitute the entire agreement of the parties and
supersede in their entirety all prior undertakings and agreements of the Company
and Optionee with respect to the subject matter hereof, and is governed by
California law except for that body of law pertaining to conflict of laws.

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Submitted by:
 
Accepted by:
 
OPTIONEE:
 
A10 NETWORKS, INC.
 
 
 
 
a California corporation
 
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By
 
 
 
 
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(address)
 
(address)
 
 
 
 
 
 
 
 
 
 
 
 

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