ATEN A10 Networks Inc

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                                                                                   
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940                       

1. Name and Address of Reporting Person * Singer Eric	2. Issuer Name and Ticker or Trading Symbol A10 Networks, Inc. [ ATEN ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director                    __X__ 10% Owner _____ Officer (give title below)    _____ Other (specify below)
(Last)          (First)          (Middle) C/O A10 NETWORKS, INC., 2300 ORCHARD PARKWAY	3. Date of Earliest Transaction (MM/DD/YYYY) 4/29/2021
(Street) SAN JOSE, CA 95131 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) ___ Form filed by One Reporting Person _ X _ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock, par value $0.00001	4/29/2021		A		16949 (1)	A	$0	73139	D (2)(3)
Common Stock, par value $0.00001								1465781	I	By Viex Opportunities Fund, LP - Series One (2)(3)(4)
Common Stock, par value $0.00001								482877	I	By Viex Opportunities Fund, LP - Series Two (2)(3)(5)
Common Stock, par value $0.00001								5255022	I	By Viex Special Opportunities Fund II, LP (2)(3)(6)
Common Stock, par value $0.00001								487416	I	By Viex Special Opportunities Fund III, LP (2)(3)(7)

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

Explanation of Responses:
(1)	Each share is represented by a Restricted Stock Unit ("RSU"). The RSUs will vest on the earlier of the first anniversary of the grant date or the date of the Issuer's next Annual Meeting, subject to the Reporting Person's continued service as of such date.
(2)	This Form 4 is filed jointly by VIEX Opportunities Fund, LP - Series One ("Series One"), a series of VIEX Opportunities Fund, LP, VIEX Opportunities Fund, LP - Series Two ("Series Two"), a series of VIEX Opportunities Fund, LP, VIEX Special Opportunities Fund II, LP ("VSO II"), Viex Special Opportunities Fund III, LP ("VSO III"), VIEX GP, LLC ("VIEX GP"), VIEX Special Opportunities GP II, LLC ("VSO GP II"), Viex Special Opportunities GP III, LLC ("VSO GP III"), VIEX Capital Advisors, LLC ("VIEX Capital"), and Eric Singer (collectively, the "Reporting Persons").
(3)	Each Reporting Person disclaims beneficial ownership of the securities of the Issuer reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such securities for purposes of Section 16 or any other purpose.
(4)	Securities of the Issuer beneficially owned directly by Series One. VIEX GP, as the general partner of Series One, may be deemed the beneficial owner of the securities of the Issuer beneficially owned bySeries One. VIEX Capital, as the investment manager of Series One, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One. Mr. Singer, as the managing member ofeach of VIEX GP and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One.
(5)	Securities of the Issuer beneficially owned directly by Series Two. VIEX GP, as the general partner of Series Two, may be deemed the beneficial owner of the securities of the Issuer beneficially owned bySeries Two. VIEX Capital, as the investment manager of Series Two, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two. Mr. Singer, as the managing memberof each of VIEX GP and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two.
(6)	Securities of the Issuer beneficially owned directly by VSO II. VSO GP II, as the general partner of VSO II, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO II.VIEX Capital, as the investment manager of VSO II, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO II. Mr. Singer, as the managing member of each of VSO GP IIand VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO II.
(7)	Securities of the Issuer beneficially owned directly by VSO III. VSO GP III, as the general partner of VSO III, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSOIII. VIEX Capital, as the investment manager of VSO III, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III. Mr. Singer, as the managing member of each of VSOGP III and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Singer Eric C/O A10 NETWORKS, INC. 2300 ORCHARD PARKWAY SAN JOSE, CA 95131	X	X
VIEX Opportunities Fund, LP Series One C/O A10 NETWORKS, INC. 2300 ORCHARD PARKWAY SAN JOSE, CA 95131		X
VIEX Opportunities Fund, LP - Series Two C/O A10 NETWORKS, INC. 2300 ORCHARD PARKWAY SAN JOSE, CA 95131		X
VIEX Special Opportunities Fund II, LP C/O A10 NETWORKS, INC. 2300 ORCHARD PARKWAY SAN JOSE, CA 95131		X
VIEX Special Opportunities Fund III, LP C/O A10 NETWORKS, INC. 2300 ORCHARD PARKWAY SAN JOSE, CA 95131		X

Signatures
/s/ Robert Cochran, Attorney-in-fact for Eric Singer		5/3/2021
**Signature of Reporting Person		Date