SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Trivedi Dhrupad (Last) (First) (Middle) C/O A10 NETWORKS, INC. 2300 ORCHARD PARKWAY (Street) SAN JOSE CA 95131 (City) (State) (Zip)	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 10% Owner X Officer (give title below) Other (specify below) Chief Executive Officer
	3. Date of Earliest Transaction (Month/Day/Year) 02/02/2021
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person 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. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction 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	02/02/2021		A		50,898(1)	A	$0	165,009	D
Common Stock	02/02/2021		M		125,000(2)	A	$0	290,009	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	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 (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		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: 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
Performance-based Restricted Stock Units	(3)	02/02/2021		A		118,762		(4)	02/02/2025	Common Stock	118,762	$0	118,762	D
Performance-based Restricted Stock Units	(2)	02/02/2021		M			125,000	(2)	12/12/2023	Common Stock	125,000	$0	250,000	D

Explanation of Responses:

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 the date of grant, provided that the Reporting Person continues to serve through each vesting date.

2. Performance-Based Restricted Stock Units were previously reported on December 16, 2019, 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 December 12, 2019 and December 12, 2023. The first achievement date occurred on January 28, 2021, as certified by the compensation committee of ATEN February 2, 2021, resulting in 125,000 units meeting the appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest as to one-third on the first, second and third anniversaries of achievement of the milestone, subject to continued employment. These shares are reflected on Table I.

3. Each share is represented by a Performance-based Restricted Stock Unit ("PSU")

4. Grant of 118,762 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 February 2, 2021 and February 2, 2025 (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 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.

Remarks:

	/s/ Robert Cochran, as Attorney-in-Fact	02/04/2021
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.