[Form 4] A10 Networks, Inc. Insider Trading Activity

Rhea-AI Filing Summary

A10 Networks (ATEN) Chief Financial Officer Michelle Caron reported grants dated 09/30/2025 totaling 13,706 shares in two award types: restricted stock units and performance-based restricted stock units. The restricted stock units vest in four equal annual installments starting on the vesting commencement date of 10/05/2025, provided continued service. The performance-based RSUs (PSUs) each represent a contingent right to one share and vest only if a specified volume-weighted average closing price milestone is achieved during any 100-day period between 09/30/2025 and 09/30/2029, then subject to continued employment with vesting in three installments: 50% within 30 days of milestone achievement and two additional 25% installments on the first and second anniversaries of achievement. The Form 4 was signed by an attorney-in-fact on 10/02/2025.

Positive

• Grant of 13,706 restricted stock units with clear annual vesting schedule beginning 10/05/2025
• Grant of 13,706 performance-based RSUs that vest only upon a defined VWAP performance milestone measured through 09/30/2029

Negative

• None.

Insights

Compensation & Governance Analyst

TL;DR: CFO received time-based RSUs and performance-based PSUs totaling 13,706 awards on 09/30/2025.

The filing shows a grant of 13,706 restricted stock units that vest one-quarter annually beginning 10/05/2025, linking a portion of pay to continued service.

The filing also discloses 13,706 performance-based restricted stock units tied to a specified VWAP milestone measured over any 100-day window between 09/30/2025 and 09/30/2029; vesting of earned PSUs occurs in 50%/25%/25% installments after the milestone and subject to continued employment.

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
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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^*

Caron Michelle Elizabeth

(Last) (First) (Middle)

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)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Financial Officer

3. Date of Earliest Transaction (Month/Day/Year)
09/30/2025

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	09/30/2025		A		13,706(1)	A	$0	13,706	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	(2)	09/30/2025		A		13,706		(3)	09/30/2029	Common Stock	13,706	$0	13,706	D

Explanation of Responses:

1. Each share is represented by a Restricted Stock Unit ("RSU"). One-fourth (1/4) of the total RSUs will vest on each of the first four (4) anniversaries of the Vesting Commencement Date (10/5/2025), 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 13,706 PSUs, each of which represents a contingent right to receive one share of common stock of ATEN, with vesting subject to the achievement of a specified level of the volume weighted average closing prices of a share of ATEN common stock during any one hundred (100) day period between September 30, 2025 and September 30, 2029 (the "Performance Milestone"). Upon achievement of the Performance Milestone, vesting is subject to continued employment with the Company through the applicable vesting date, which occurs in three installments, with the vesting of the first fifty percent (50%) to occur within thirty (30) days of achievement of the Performance Milestone and an additional twenty-five percent (25%) on each of the first and second anniversaries of the date of achievement of the Performance Milestone.

Remarks:

	/s/ Jill Osato, as Attorney-in-Fact	10/02/2025
	** 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.

FAQ

What did the ATEN Form 4 filed for Michelle Caron report?

The Form 4 reports grants dated 09/30/2025 of 13,706 restricted stock units and 13,706 performance-based RSUs to CFO Michelle Caron.

When do the restricted stock units for ATEN vest?

The RSUs vest in four equal annual installments beginning on the vesting commencement date of 10/05/2025, subject to continued service.

What performance period applies to the ATEN PSUs?

The PSUs require achievement of a specified VWAP milestone during any 100-day period between 09/30/2025 and 09/30/2029.

How do PSUs vest after the performance milestone is achieved?

Upon milestone achievement, vesting occurs in three installments: 50% within 30 days of achievement, then 25% on each of the first and second anniversaries, subject to continued employment.

Who signed the Form 4 and when was it signed?

The Form 4 was signed by Jill Osato, as Attorney-in-Fact on 10/02/2025.