FORM 4
Check this box if no longer subject to Section 16, Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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1. Name and Address of Reporting Person *
BRUENING MATTHEW P
  2. Issuer Name and Ticker or Trading Symbol
A10 Networks, Inc. [ATEN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
EVP, Worldwide Sales & Mktg /
(Last)
(First)
(Middle)
  C/O A10 NETWORKS , 2300 ORCHARD PARKWAY
3. Date of Earliest Transaction (Month/Day/Year)
(Street)

  SAN JOSE   CA   95131
4. If Amendment, Date Original Filed (Month/Day/Year)
6. Individual or Join/Group Filing (Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code 4. Securities Acquired (A) or Disposed of (D) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) 6. Ownership Form: Direct (D) or Indirect (I) 7. Nature of Indirect Beneficial Ownership
Code V Amount (A) or (D) Price

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code 5. Number of Derivative Securities Acquired (A) or Disposed of (D) 6. Date Exercisable and Expiration Date 7. Title and Amount of Securities Underlying Derivative Security 8. Price of Derivative Security 9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) 11. Nature of Indirect Beneficial Ownership
Code V (A) (D)   Date Exercisable   Expriation Date   Title   Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
BRUENING MATTHEW P
C/O A10 NETWORKS
2300 ORCHARD PARKWAY
SAN JOSE, CA95131


EVP, Worldwide Sales & Mktg  

Signatures

 /s/ Robert Cochran, Attorney-in-fact  2022-01-27
**Signature of Reporting Person Date

Explanation of Responses:

(*) If the form is filed by more than one reporting person, see Instruction 5(b)(v).
(**) Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Each share is represented by a Restricted Stock Unit ("RSU"). One-third (1/3) of the total RSUs will vest on each of the first three (3) anniversaries of February 2, 2022, provided that the Reporting Person continues to serve through each vesting date.
(2) Each share is represented by a Performance-based Restricted Stock Unit ("PSU")
(3) Grant of 36,534 Performance-Based Restricted Stock Units, each of which represents a contingent right to receive one share of common stock of ATEN, with vesting subject to the achievement of specified levels of the volume weighted average closing prices of a share of ATEN common stock during any one hundred (100) day trading period between January 25, 2022 and January 25, 2026 (each, a "Performance Milestone"). Upon achievement of a Performance Milestone, vesting is subject to continued employment with the Company through the applicable vesting date, which occurs in three equal installments with the first vesting to occur within thirty (30) days of achievement of the respective Performance Milestone and an additional one-third (1/3) on each of the first and second anniversaries of the date of achievement of the corresponding Performance Milestone.

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