HiddenLayer raises USD 100 million Series B for AI security
Good for: Leaders · Operators · Insurance
On 2 September 2026, AI security company HiddenLayer announced a USD 100 million Series B round led by Delta-v Capital. Ten Eleven Ventures, Morgan Stanley, M12 (Microsoft’s venture fund) and Booz Allen Ventures also took part, according to the company. No valuation was disclosed.
What happened
HiddenLayer, based in Austin, Texas, describes itself as an AI security company that secures agentic, generative and predictive AI applications. Its platform covers AI discovery, AI supply chain security, attack simulation and runtime protection. The company said it would use the funding to deepen its enterprise platform, including its Agentic Runtime Security capabilities and Agent Harness Security, which it calls a new solution that extends its Runtime Security module to AI coding agents. It also said it is adding staff and channel partners and pushing further into international markets, beginning with Europe and the wider EMEA region.
HiddenLayer said that in what it called a standout year its annual recurring revenue grew more than tenfold and it signed more than 50 new platform customers, with customers in sectors including banking, securities brokerage, insurance, accounting, government, technology, and defense and intelligence. These are the company’s own figures. Law firm Holland & Knight, which advised HiddenLayer, confirmed the amount, the lead investor and the participating investors.
Why it matters
Security for AI is one of the testing and live-control layers of AI assurance: it produces evidence about how a model or agent behaves under attack and enforces controls while it runs. Since 2024 larger security vendors have bought, or agreed to buy, several independent companies in this category, among them Robust Intelligence (Cisco), Protect AI (Palo Alto Networks) and Lakera (Check Point), as tracked on the AI Risk Timeline. A round of this size shows capital still going to independents as well. The product focus on AI agents and coding agents matches the exposures that insurers and risk teams are now trying to assess, set out in the AI risk stack.
What is not yet clear
The company did not disclose its valuation, revenue in absolute terms or a timetable for Agent Harness Security.