A10 Networks, Inc. — Director's Dealing 2020

May 20, 2020

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: A10 Networks, Inc. (ATEN)
CIK: 0001580808
Period of Report: 2020-05-18

Reporting Person: CHEN LEE (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2020-05-18	Common Stock	S	2200000	$6.00	Disposed	7670224	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2020-05-18	Employee Stock Option (right to buy)	$5.52	S	282500	Disposed	2020-05-31	Common Stock (282500)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	3200	Indirect

Footnotes

F1: The Issuer and Reporting Person entered into a Common Stock Repurchase and Option Exchange Agreement (the "Repurchase Agreement") for the purchase by the Issuer, and sale by the Reporting Person, of 2,200,000 shares of the Issuer's common stock in a privately-negotiated transaction for an aggregate purchase price of $13,200,000.

F2: Shares held of record by the U/A DTD 07/25/2000 Lee Chen Family Trust, for which the Reporting Person serves as a trustee.

F3: Represents fully vested stock options.

F4: Pursuant to the Repurchase Agreement, in addition to the purchase and sale of common stock referenced in footnote 1, the Reporting Person agreed to cancel such options in exchange for the payment by the Issuer to the Reporting Person of $135,600.

F5: Following Reporting Person's separation from service, the stock options expire if not exercised by May 31, 2020.