Law Firms Seek F5 Investors Before Feb. 17 Lead-Plaintiff Deadline in Securities Suit Over 2025 Breach

The litigation accuses F5 of downplaying an August 2025 nation-state intrusion that reached its BIG-IP development systems.

Overview

Smith v. F5, Inc., No. 25-cv-02619, is pending in the U.S. District Court for the Western District of Washington, and no class has been certified.
Plaintiffs allege F5 and certain executives misled investors about security capabilities and prospects while the company was experiencing a significant breach.
F5 disclosed on October 15, 2025 that a sophisticated actor maintained persistent access and downloaded files, including from BIG-IP development and engineering platforms.
On October 27, 2025, F5 issued weaker fiscal 2026 guidance citing reduced sales, elongated sales cycles, and higher remediation costs tied to the breach, and the complaint cites stock drops of about 14% and 11% after the two disclosures.
The putative class period spans October 28, 2024 through October 27, 2025, and multiple firms are soliciting lead-plaintiff candidates ahead of the February 17, 2026 deadline.