A10 Networks Inc.

05/06/2026 | Press release | Distributed by Public on 05/06/2026 19:30

Statement of Changes in Beneficial Ownership (Form 4)

FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Weber Robert Scott
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)
General Counsel
(Last) (First) (Middle)
C/O A10 NETWORKS, INC., 2300 ORCHARD PARKWAY
3. Date of Earliest Transaction (Month/Day/Year)
05/05/2026
(Street)
SAN JOSE, CA 95131
4. If Amendment, Date 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
(City) (State) (Zip)
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 05/05/2026 M 3,882(1) A $ 0 58,092 D
Common Stock 05/05/2026 M 3,707(2) A $ 0 61,799 D
Common Stock 05/06/2026 F 1,930(3) D $27.13 59,869 D
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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 Underlying Securities
(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 of Derivative Security: 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 (1) 05/05/2026 M 3,882 (1) 02/06/2029 Common Stock 3,882 $ 0 3,882 D
Performance-based Restricted Stock Units (2) 05/05/2026 M 3,707 (2) 02/12/2030 Common Stock 3,707 $ 0 3,706 D

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Weber Robert Scott
C/O A10 NETWORKS, INC.
2300 ORCHARD PARKWAY
SAN JOSE, CA 95131
General Counsel

Signatures

/s/ Jill Osato, Attorney-in-fact 05/06/2026
**Signature of Reporting Person Date

Explanation of Responses:

* 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).
(1) Performance-Based Restricted Stock Units were previously reported on February 10, 2025, 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 6, 2025 and February 6, 2029. The first achievement date occurred on April 16, 2026, as certified by the compensation committee of ATEN, resulting in 3,882 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 May 5, 2026 and an additional one-fourth (1/4) on each of the first and second anniversaries of April 16, 2026, subject to continued employment. These shares are reflected on Table I.
(2) Performance-Based Restricted Stock Units that were previously reported on February 13, 2026, 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 12, 2026 and February 12, 2030. The first achievement date occurred on April 22, 2026, as certified by the compensation committee of ATEN, resulting in 3,707 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 May 5, 2026 and an additional one-fourth (1/4) on each of the first and second anniversaries of April 22, 2026, subject to continued employment. These shares are reflected on Table I.
(3) Includes 987 shares and 943 shares automatically withheld, on a non-discretionary basis, for tax purposes related to a February 6, 2025 performance-based restricted stock unit grant and a February 12, 2026 performance-based restricted stock unit grant, respectively, each that vested on May 5, 2026.
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure. Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.
A10 Networks Inc. published this content on May 06, 2026, and is solely responsible for the information contained herein. Distributed via EDGAR on May 07, 2026 at 01:30 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]