A10 Networks, Inc. — Director's Dealing 2021

Feb 5, 2021

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: A10 Networks, Inc. (ATEN)
CIK: 0001580808
Period of Report: 2021-02-02

Reporting Person: Becker Brian (Interim CFO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2021-02-02	Common Stock	A	11976	—	Acquired	42504	Direct
2021-02-02	Common Stock	M	3250	—	Acquired	45754	Direct
2021-02-02	Common Stock	M	3333	—	Acquired	49087	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2021-02-02	Performance-based Restricted Stock Units	$	A	27944	Acquired	2025-02-02	Common Stock (27944.0)	Direct
2021-02-02	Performance-based Restricted Stock Units	$	M	3250	Disposed	2024-07-20	Common Stock (3250.0)	Direct
2021-02-02	Performance-based Restricted Stock Units	$	M	3333	Disposed	2024-10-19	Common Stock (3333.0)	Direct

Footnotes

F1: 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.

F2: Performance-Based Restricted Stock Units were previously reported on September 25, 2020, 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 July 20, 2020 and July 20, 2024. The achievement date occurred on January 28, 2021, as certified by the compensation committee of ATEN on February 2, 2021, resulting in 3,250 units meeting the appropriate performance-based conditions. These shares will therefore vest as to one-half within thirty (30) days of the date of achievement of the milestone with an additional one-fourth on each of the first and second anniversaries of achievement of the milestone, subject to continued employment. These shares are reflected on Table I.

F3: Performance-Based Restricted Stock Units were previously reported on October 21, 2020, 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 October 19, 2020 and October 19, 2024. The first achievement date occurred on January 28, 2021, as certified by the compensation committee of ATEN on February 2, 2021, resulting in 3,333 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 within 30 days of achievement of the milestone and an additional one-third on each of the first and second anniversaries of achievement of the milestone, subject to continued employment. These shares are reflected on Table I.

F4: Each share is represented by a Performance-based Restricted Stock Unit ("PSU")

F5: Grant of 27,944 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.