Vanguard Portfolio Management filed a Schedule 13G with the SEC on October 30, 2026, disclosing beneficial ownership of 3,788,363 shares of A10 Networks Inc common stock, representing 5.21% of the class, as of September 30, 2026.

Key Highlights

  • Aggregate beneficial ownership: Vanguard Portfolio Management reported beneficial ownership of 3,788,363 shares of A10 Networks Inc common stock.
  • Percent of class: The reported position represents 5.21% of the outstanding common stock, according to the filing.
  • Sole voting power: Vanguard Portfolio Management disclosed sole power to vote or direct the vote of 66,757 shares.
  • Sole dispositive power: The filing reports sole power to dispose or direct the disposition of 3,788,363 shares, with no shared dispositive power reported.
  • Triggering date: The event requiring the filing occurred on September 30, 2026.
  • Filing entity type: Vanguard Portfolio Management is identified as an investment adviser (type "IA"), organized in Pennsylvania.

Vanguard Portfolio Management Crosses 5% Threshold in A10 Networks Common Stock

According to the Schedule 13G filed on October 30, 2026, Vanguard Portfolio Management LLC, headquartered at 100 Vanguard Blvd, Malvern, PA 19355, disclosed that it beneficially owns 3,788,363 shares of common stock (CUSIP 002121101) in A10 Networks Inc (NYSE:ATEN), whose principal executive offices are located at 3 West Plumeria Drive, San Jose, CA 95134. The filing states the triggering event date was September 30, 2026.

The filing discloses that Vanguard Portfolio Management holds sole voting power over 66,757 shares and sole dispositive power over the full 3,788,363 shares. Shared voting power and shared dispositive power are each reported as zero. The filing notes that it reflects securities beneficially owned by Vanguard Portfolio Management LLC and affiliates including Vanguard Fiduciary Trust Company and Vanguard Global Advisers, LLC, as well as securities held by Vanguard funds or sleeves thereof over which Vanguard Portfolio Management LLC exercises dispositive power.

Regarding the right to receive dividends or sale proceeds, the filing states: "Vanguard Portfolio Management, including investment companies registered under the Investment Company Act of 1940 and other managed accounts, have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities reported herein." The filing further states that "No one other person's interest in the securities reported herein is more than 5%." The filing was signed by My Trieu-Gatt, identified as Authorized Signatory, Head of Global Fund Administration, on October 30, 2026.

What Was Disclosed

Vanguard Portfolio Management filed a Schedule 13G reporting beneficial ownership of 3,788,363 shares, or 5.21%, of A10 Networks Inc common stock as of September 30, 2026, with sole dispositive power over all reported shares and sole voting power over 66,757 shares.