Armadin Raises $255.5 Million to Scale AI Agent Swarms for Cyber Defense

Armadin, the AI-native cybersecurity startup led by Mandiant founder Kevin Mandia, raised a $255.5 million Series B at a valuation above $2.5 billion to expand autonomous agent swarms that test enterprise defenses. The round, co-led by Andreessen Horowitz and Accel, lifts disclosed funding to $445 million seven months after the company emerged from stealth.