A10 Networks, Inc. — Director's Dealing 2019

Jul 30, 2019

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: A10 Networks, Inc. (ATEN)
CIK: 0001580808
Period of Report: 2019-07-26

Reporting Person: Singer Eric (Director)
Reporting Person: VIEX Opportunities Fund, LP Series One (See Explanation of Responses)
Reporting Person: VIEX Opportunities Fund, LP - Series Two (See Explanation of Responses)
Reporting Person: VIEX Special Opportunities Fund II, LP (See Explanation of Responses)
Reporting Person: VIEX Special Opportunities Fund III, LP (See Explanation of Responses)
Reporting Person: VIEX GP, LLC (See Explanation of Responses)
Reporting Person: VIEX Special Opportunities GP II, LLC (See Explanation of Responses)
Reporting Person: VIEX Special Opportunities GP III, LLC (See Explanation of Responses)
Reporting Person: VIEX Capital Advisors, LLC (See Explanation of Responses)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2019-07-26	Common Stock, par value $0.00001	A	30120	—	Acquired	30120	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock, par value $0.00001	1658360	Indirect
Common Stock, par value $0.00001	331977	Indirect
Common Stock, par value $0.00001	3531222	Indirect
Common Stock, par value $0.00001	271116	Indirect

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Call Option (Right to Buy)	$2.50	2019-11-15	Common Stock, par value $0.00001 (150900)	1509	Indirect
Call Option (Right to Buy)	$2.50	2019-11-15	Common Stock, par value $0.00001 (150000)	1500	Indirect
Call Option (Right to Buy)	$5.00	2019-11-15	Common Stock, par value $0.00001 (5900)	59	Indirect
Put Option (Obligation to Buy)	$5.00	2019-08-16	Common Stock, par value $0.00001 (111700)	1117	Indirect
Put Option (Obligation to Buy)	$7.50	2019-08-16	Common Stock, par value $0.00001 (1367900)	13679	Indirect
Put Option (Obligation to Buy)	$7.50	2019-11-15	Common Stock, par value $0.00001 (200000)	2000	Indirect
Call Option (Right to Buy)	$2.50	2019-11-15	Common Stock, par value $0.00001 (210500)	2105	Indirect
Call Option (Right to Buy)	$5.00	2019-11-15	Common Stock, par value $0.00001 (5800)	58	Indirect

Footnotes

F1: This Form 4 is filed jointly by VIEX Opportunities Fund, LP - Series One ("Series One"), a series of VIEX Opportunities Fund, LP, VIEX Opportunities Fund, LP - Series Two ("Series Two"), a series of VIEX Opportunities Fund, LP, VIEX Special Opportunities Fund II, LP ("VSO II"), Viex Special Opportunities Fund III, LP ("VSO III"), VIEX GP, LLC ("VIEX GP"), VIEX Special Opportunities GP II, LLC ("VSO GP II"), Viex Special Opportunities GP III, LLC ("VSO GP III"), VIEX Capital Advisors, LLC ("VIEX Capital"), and Eric Singer (collectively, the "Reporting Persons").

F2: Each share is represented by a restricted stock unit, which vests in three equal annual installments on the anniversary of the grant date of 07/26/2019, provided that the Reporting Person continues to serve through each vesting date.

F3: Securities of A10 Networks, Inc. (the "Issuer") beneficially owned directly by Series One. VIEX GP, as the general partner of Series One, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One. VIEX Capital, as the investment manager of Series One, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One. Mr. Singer, as the managing member of each of VIEX GP and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series One.

F4: Securities of the Issuer beneficially owned directly by Series Two. VIEX GP, as the general partner of Series Two, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two. VIEX Capital, as the investment manager of Series Two, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two. Mr. Singer, as the managing member of each of VIEX GP and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by Series Two.

F5: Securities of the Issuer beneficially owned directly by VSO II. VSO GP II, as the general partner of VSO II, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO II. VIEX Capital, as the investment manager of VSO II, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO II. Mr. Singer, as the managing member of each of VSO GP II and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO II.

F6: Securities of the Issuer beneficially owned directly by VSO III. VSO GP III, as the general partner of VSO III, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III. VIEX Capital, as the investment manager of VSO III, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III. Mr. Singer, as the managing member of each of VSO GP III and VIEX Capital, may be deemed the beneficial owner of the securities of the Issuer beneficially owned by VSO III.

F7: Each Reporting Person disclaims beneficial ownership of the securities of the Issuer reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.