Robert Scott Weber - 14 May 2026 Form 4 Insider Report for A10 Networks, Inc. (ATEN)

Reporting relationship: General Counsel
Issuer ticker: ATEN
Reported as of: 14 May 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 15 May 2026, 17:50:50 UTC
Prior SEC filing: 06 May 2026
Next SEC filing: 15 May 2026
Source filing: View source filing
Reporting owner signature: /s/ Jill Osato, Attorney-in-fact

Key filing fact

Robert Scott Weber filed Form 4 for A10 Networks, Inc. (ATEN) on 15 May 2026.

Key facts

This page summarizes Robert Scott Weber's Form 4 filing for A10 Networks, Inc. (ATEN).
5 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 15 May 2026, 17:50.

Change

Previous filing in this sequence was filed on 06 May 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001936128 Primary reporting owner

Weber Robert Scott

Relationship: General Counsel
Address: C/O A10 NETWORKS, INC., 2300 ORCHARD PARKWAY, SAN JOSE
Signature: /s/ Jill Osato, Attorney-in-fact
Signature date: 15 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

ATEN transaction

Common Stock

Options Exercise

Transaction value
Shares: +3,706
Change %: +6.2%
Price: $0.000000^*
Shares after: 63,575
Date: 14 May 2026
Ownership: Direct
Footnotes: F1

ATEN transaction

Common Stock

Options Exercise

Transaction value
Shares: +3,882
Change %: +6.1%
Price: $0.000000^*
Shares after: 67,457
Date: 14 May 2026
Ownership: Direct
Footnotes: F2

ATEN transaction

Common Stock

Tax liability

Transaction value
Shares: -1,930
Change %: -2.9%
Price: $27.00^*
Shares after: 65,527
Date: 15 May 2026
Ownership: Direct
Footnotes: F3

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

ATEN transaction Derivative

Performance-based Restricted Stock Units

Options Exercise

Transaction value
Shares: -3,706
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 14 May 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 3,706
Exercise price
Footnotes: F1

ATEN transaction Derivative

Performance-based Restricted Stock Units

Options Exercise

Transaction value
Shares: -3,882
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 14 May 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 3,882
Exercise price
Footnotes: F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

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 second achievement date occurred on April 27, 2026, as certified by the compensation committee of ATEN, resulting in 3,706 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 14, 2026 and an additional one-fourth (1/4) on each of the first and second anniversaries of April 27, 2026, subject to continued employment. These shares are reflected on Table I.

Footnote F2

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 second achievement date occurred on May 6, 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 14, 2026 and an additional one-fourth (1/4) on each of the first and second anniversaries of May 6, 2026, subject to continued employment. These shares are reflected on Table I.

Footnote F3

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 14, 2026.