A10 Networks, Inc. — Director's Dealing 2025

Mar 12, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: A10 Networks, Inc. (ATEN)
CIK: 0001580808
Period of Report: 2025-03-10

Reporting Person: Becker Brian (Chief Financial Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-03-10	Common Stock	M	7306	—	Acquired	77681	Direct
2025-03-10	Common Stock	M	10125	—	Acquired	87806	Direct
2025-03-11	Common Stock	F	3807	$19.38	Disposed	83999	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-03-10	Performance-based Restricted Stock Units	$0	M	7306	Disposed	2026-01-25	Common Stock (7306)	Direct
2025-03-10	Performance-based Restricted Stock Units	$	M	10125	Disposed	2027-02-21	Common Stock (10125)	Direct

Footnotes

F1: Performance-Based Restricted Stock ("PSUs") Units were previously reported on January 27, 2022, 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. The third achievement date occurred on February 24, 2025, as certified by the compensation committee of ATEN, resulting in 7,306 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 (1/3) on March 10, 2025 and an additional one-third (1/3) to vest on the each of the first and second anniversaries of February 24, 2025, subject to continued employment. These shares are reflected on Table I.

F2: PSUs that were previously reported on February 22, 2023, 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 21, 2023 and February 21, 2027. The second achievement date occurred on February 28, 2025, as certified by the compensation committee of ATEN, resulting in 10,125 units meeting the
appropriate performance-based conditions. However, these shares remain subject to time-based vesting conditions and will therefore vest as to one-half (1/2) on March 10, 2025 and an additional one-fourth (1/4) on each of the first and second anniversaries of February 28, 2025, subject to continued employment. These shares are reflected on Table I.

F3: Includes 1,237 shares automatically withheld, on a non-discretionary basis, for tax purposes related to a January 25, 2022 performance restricted stock unit grant, and 2,570 shares automatically
withheld, on a non-discretionary basis, for tax purposes related to a February 21, 2023 performance restricted stock unit grant, each that vested on March 10, 2025.