Prepared by R.R. Donnelley Financial -- EX-4.1




 Exhibit 4.1 
  






 
 . ZQ|CERT#|COY|CLS|RGSTRY|ACCT#|TRANSTYPE|RUN#|TRANS# 
COMMON STOCK PAR VALUE $0.00001 
A10R 
COMMON STOCK 
THIS CERTIFICATE IS TRANSFERABLE IN CANTON, MA, JERSEY CITY, NJ AND COLLEGE
STATION, TX 
Certificate Number ZQ00000000 
A10 NETWORKS, INC. 
INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE 
THIS CERTIFIES THAT 
Shares 
**000000 ****************** 
***000000 ***************** 
****000000 **************** 
*****000000 *************** 
******000000 ************** 
MR. SAMPLE & MRS. SAMPLE & MR. SAMPLE & MRS. SAMPLE 
** Mr. Alexander David Sample
**** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David
Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander 
David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample**** Mr.
Alexander David Sample **** Mr. Alexander David Sample **** Mr Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample
**** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David
Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander
David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr. Alexander David Sample **** Mr.
Alexander David Sample **** Mr. Sample **** Mr. Sample 
CUSIP 002121 10 1 
SEE
REVERSE FOR CERTAIN DEFINITIONS 
is the owner of 
***ZERO HUNDRED THOUSAND

ZERO HUNDRED AND ZERO***

**000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**Shares**** 
000000**Shares****000000**Shares****000000**Shares****000000**Shares****000000**S 
FULLY-PAID
AND NON-ASSESSABLE SHARES OF COMMON STOCK OF 
A10 Networks, Inc. (hereinafter called the “Company”), transferable on the books of the Company in person or
by duly authorized attorney, upon surrender of this Certificate properly endorsed. This Certificate and the shares represented hereby, are issued and shall be held subject to all of the provisions of the Certificate of Incorporation, as amended, and
the By-Laws, as amended, of the Company (copies of which are on file with the Company and with the Transfer Agent), to all of which each holder, by acceptance hereof, assents. This Certificate is not valid unless countersigned and registered by the
Transfer Agent and Registrar. 
Witness the facsimile seal of the Company and the facsimile signatures of its duly authorized officers. 
President 
Secretary 
A10 NETWORKS, INC. SEAL 2014 DELAWARE 
DATED DD-MMM-YYYY 
COUNTERSIGNED AND REGISTERED: 
COMPUTERSHARE TRUST COMPANY, N.A. 
TRANSFER AGENT AND REGISTRAR, 
By AUTHORIZED SIGNATURE 
1234567 
A10 
PO BOX 43004, Providence, RI 02940-3004 
MR A SAMPLE 
DESIGNATION (IF ANY) 
ADD 1 ADD 2 ADD 3 ADD 4 
CUSIP XXXXXX XX X 
Holder ID XXXXXXXXXX 
Insurance Value 1,000,000.00 
Number of Shares 123456 
DTC 12345678 123456789012345 
Certificate Numbers Num/No. Denom. Total 
1234567890/1234567890 1 1 1 
1234567890/1234567890 2 2 2 
1234567890/1234567890 3 3 3 
1234567890/1234567890 4 4 4 
1234567890/1234567890 5 5 5 
1234567890/1234567890 6 6 6 
Total Transaction 7 








 



 
 A10 NETWORKS, INC. 
THE COMPANY WILL FURNISH
WITHOUT CHARGE TO EACH SHAREHOLDER WHO SO REQUESTS, A SUMMARY OF THE POWERS, DESIGNATIONS, PREFERENCES AND RELATIVE, PARTICIPATING, OPTIONAL OR OTHER SPECIAL RIGHTS OF EACH CLASS OF STOCK OF THE COMPANY AND THE QUALIFICATIONS, LIMITATIONS OR
RESTRICTIONS OF SUCH PREFERENCES AND RIGHTS, AND THE VARIATIONS IN RIGHTS, PREFERENCES AND LIMITATIONS DETERMINED FOR EACH SERIES, WHICH ARE FIXED BY THE CERTIFICATE OF INCORPORATION OF THE COMPANY, AS AMENDED, AND THE RESOLUTIONS OF THE BOARD OF
DIRECTORS OF THE COMPANY, AND THE AUTHORITY OF THE BOARD OF DIRECTORS TO DETERMINE VARIATIONS FOR FUTURE SERIES. SUCH REQUEST MAY BE MADE TO THE OFFICE OF THE SECRETARY OF THE COMPANY OR TO THE TRANSFER AGENT. THE BOARD OF DIRECTORS MAY REQUIRE THE
OWNER OF A LOST OR DESTROYED STOCK CERTIFICATE, OR HIS LEGAL REPRESENTATIVES, TO GIVE THE COMPANY A BOND TO INDEMNIFY IT AND ITS TRANSFER AGENTS AND REGISTRARS AGAINST ANY CLAIM THAT MAY BE MADE AGAINST THEM ON ACCOUNT OF THE ALLEGED LOSS OR
DESTRUCTION OF ANY SUCH CERTIFICATE. 
The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they
were written out in full according to applicable laws or regulations: 
TEN COM

- as tenants in common 
UNIF GIFT MIN ACT - 
Custodian 
TEN ENT 
- as tenants by the entireties 
(Cust) 
under Uniform Gifts to Minors Act 
(Minor) 
(State) 
JT TEN 
- as joint tenants with right of survivorship and not as tenants in common 
UNIF TRF MIN ACT-

Custodian (until age) 
(Cust) 
under Uniform Transfers to Minors Act 
(Minor) 
(State) 
Additional abbreviations may also be used though not in the above list. 
PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE 
For value received,
hereby sell, assign and transfer unto 
(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING POSTAL ZIP CODE, OF ASSIGNEE) 
Shares 
of the common stock represented by the within Certificate, and do hereby irrevocably
constitute and appoint 
Attorney 
to transfer the said stock on the books of
the within-named Company with full power of substitution in the premises. 
Signature(s) Guaranteed: Medallion Guarantee Stamp 
Dated: 20 
Signature(s) Guaranteed: Medallion Guarantee Stamp 
THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (Banks, Stockbrokers, Savings and Loan Associations and Credit Unions) WITH MEMBERSHIP IN AN APPROVED
SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO S.E.C. RULE 17Ad-15. 
Signature: 
Signature: 
Notice: 
The signature to this assignment must correspond with the name as written upon the face of the certificate, in every particular, without alteration or enlargement, or any change
whatever. 
The IRS requires that we report the cost basis of certain shares acquired after January 1, 2011. If your shares were covered by the legislation and
you have sold or transferred the shares and requested a specific cost basis calculation method, we have processed as requested. If you did not specify a cost basis calculation method, we have defaulted to the first in, first out (FIFO) method.
Please visit our website or consult your tax advisor if you need additional information about cost basis. 
If you do not keep in contact with us or do not have any
activity in your account for the time periods specified by state law, your property could become subject to state unclaimed property laws and transferred to the appropriate state. 
SECURITY INSTRUCTIONS 
THIS IS WATERMARKED PAPER DO NOT ACCEPT WITHOUT NOTHING WATERMARK. HOLD
TO LIGHT TO VERIFY WATERMARK 
1234567