Kevin Mandia, who founded the cybersecurity firm Mandiant and sold it to Google for $5.4 billion in 2022, has raised $255.5 million for his new security startup, Armadin, at a valuation of $2.5 billion.
The round arrives just six months after Armadin closed a $190 million Series A in March. The company has now raised more than $445 million in total, making it one of the fastest-capitalized security startups in recent memory.
Armadin builds what it calls "agent swarm" security technology — networks of autonomous AI agents that hunt for threats and respond to intrusions together rather than through a single centralized tool. The approach targets the speed problem at the center of modern breaches, where attackers can move through a corporate network in hours while human defenders are still triaging alerts.
Mandia spent nearly two decades building Mandiant into the firm enterprises called when they suspected they had been hacked. Google bought it in 2022 and folded it into Google Cloud, and Mandia later left the company. His return to the startup world with a $2.5 billion price tag before shipping a widely known product reflects both his track record and investor appetite for AI-driven security tools.
The funding pace sets Armadin apart even in a crowded field. Raising $445 million within roughly six months of launch is unusual for a security company at any stage, and it signals that backers expect the firm to compete for the large enterprise contracts currently held by established vendors.
Demand for that kind of spending has grown as breach costs climb. IBM's annual Cost of a Data Breach report put the global average at $4.88 million in 2024, a 10% jump from the prior year — the largest increase since the pandemic. Security budgets have followed, with AI-based detection and response drawing a disproportionate share of new investment.
Armadin has not disclosed which investors led the round or named its customers. The company also has not said when its agent-swarm platform will be generally available.
Mandia's last venture ended in one of the largest cybersecurity acquisitions on record. Whether Armadin can repeat that outcome will depend on whether autonomous agents can do what Mandiant's human incident responders did for two decades: find intruders that conventional software misses.
