Cybersecurity vendor F5 reached an agreement to acquire AI security firm CalypsoAI in a deal worth $180 million.

The acquisition, expected to close by the end of September, will see F5 snap up a firm that provides a platform that secures AI systems, applications, and agents at the inference layer.

CalypsoAI’s offerings will be integrated into F5’s Application Delivery and Security Platform (ADSP) to provide enterprise customers with security for their AI stack.

“AI is redefining enterprise architecture – and the attack surface companies must defend,” F5 CEO and President François Locoh-Donou, noted in a statement on the deal. “Traditional firewalls and point solutions can’t keep up. The addition of CalypsoAI will give enterprises the confidence to innovate faster and better protect critical data as they rely on F5 to deliver and secure apps, APIs, and AI models across their environment.”

CalypsoAI was founded in 2018 by Neil Serebryany. The startup is led by Qualtrics and McKinsey alumni Donnchadh Casey and has offices in both New York and Dublin.

The firm has raised more than $40 million in venture funding from backers including Paladin Capital Group, Lockheed Martin Ventures, and Hakluyt Capital.

CalypsoAI’s platform creates what it describes as an “inference perimeter” – effectively a security layer designed to protect AI systems from attacks like jailbreaks, prompt injections (where an attacker crafts manipulative inputs to override the AI's original instructions), and data exfiltration.

F5 said the addition of the startup’s AI security technology will help protect customers from emerging AI-focused attacks, enabling security teams to detect and prevent sensitive data leakage and policy violations.

“Enterprises want to move fast with AI while reducing the risk of data leaks, unsafe outputs, or compliance failures,” Casey said. “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.”

F5’s CalypsoAI deal makes it the second acquisition in two months for the company, following its recent acquisition of cloud-observability vendor MantisNet.

The acquisitions come as F5 is cutting some 106 roles from its base in Washington state – despite the vendor posting third-quarter revenues of $780 million, a 12% growth year over year.