Four years ago Kevin Mandia agreed to sell his cybersecurity company Mandiant to Google for $5.4 billion. Now he’s back in the game, with Google’s help.

On Tuesday, Mandia’s new startup, Armadin, said it raised nearly $190 million, in a funding round led by Accel. Google Ventures is participating, along with firms including Kleiner Perkins, Menlo Ventures and Ballistic Ventures, which Mandia co-founded.

Mandia told CNBC in an interview that the emergence of artificial intelligence, particularly agentic AI, is having a dramatic impact on cybersecurity. Armadin creates and manages autonomous AI agents that consistently scan for threats.

“I wasn’t going to sit on the sidelines watching another shift change in cybersecurity without leveraging 30 years in the industry to do something,” Mandia said.

Across the tech world, companies are offering more AI-enabled tools and acquiring cyber capabilities in a scramble to supercharge their defenses as attacks rise in sophistication, speed, and intensity. Mandia co-founded Armadin in September and, in the past six months, the company has hired over 60 employees and started working with Fortune 100 companies.

Mandia said Armadin is using agentic tools to complete tasks that previously took days in a matter of minutes. He said the company’s name came to him in the middle of the night, while reflecting on the 1588 Spanish Armada.

“Somehow my brain remembered eighth-grade history,” he said.

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