Seattle-based security and application delivery giant F5 will pay $180 million to acquire CalypsoAI, a startup founded in 2018 that helps companies secure their generative AI infrastructure.
The deal is financed primarily with cash and is expected to close this month, F5 said in a news release.
Founded in 2018 with offices in Ireland and New York City, Calypso provides real-time threat defense and other data security products to customers deploying AI-related workloads.
“AI is redefining enterprise architecture — and the attack surface companies must defend,” François Locoh-Donou, president and CEO of F5, said in a statement.
CalypsoAI raised $23 million in 2023. Its backers include Paladin Capital Group; Lockheed Martin Ventures; Hakluyt Capital; Expeditions Fund; and others.
“Our customers rely on us to pressure test AI systems at scale, set inference layer guardrails that adapt as models change, and to gain visibility and auditability across their AI estate,” CalypsoAI CEO Donnchadh Casey said in a statement.
Funding to cybersecurity startups reached a three-year high in the first half of 2025.
F5 acquired San Francisco cybersecurity startup Fletch in June and swooped up observability company MantisNet in August.
F5 topped estimates for its fiscal third quarter, with revenue up 12% to $780 million. GAAP net income was $190 million, up from $144 million.
The company’s stock is up more than 30% this year.
