HiddenLayer Nabs $100M as Enterprises Rush to Secure AI Deployments

AI security is suddenly a booming market — and HiddenLayer is cashing in with a $100M Series B.

Published: 2026-09-03 Category: Quick Take Sources: TechCrunch

The Story

AI security startup HiddenLayer has raised $100 million in a Series B led by Delta-v Capital, with participation from Ten Eleven Ventures, Morgan Stanley, Microsoft's M12, Booz Allen Hamilton, and others. The Austin-based company makes tools to protect AI models, agents, and workflows from adversarial attacks, vulnerabilities, and malicious code injections.

The raise reflects a dramatic market shift. When HiddenLayer raised its $50M Series A three years ago, it was hard to pin down real examples of attacks against AI at scale. Now Gartner estimates companies will spend $2.83 billion this year on AI security products — 83% more than 2025 — and expects spending to approach $4.78 billion next year.

Why It Matters

HiddenLayer's growth tells the story. CEO Chris Sestito says annual recurring revenue grew more than 10x over the past year, now in the "tens of millions," with over 90% of that growth from new customers. Its largest verticals are financial services and large tech companies, and it holds contracts with the Department of Defense and intelligence community. One customer is apparently a "leading frontier model provider" with "more than 700 million weekly users" — which sounds like OpenAI or Anthropic.

The company has extended its products — discovery, runtime protection, attack simulation, and supply chain security — to address prompt injection, agent manipulation, and malicious tool use. Sestito likens runtime security to endpoint detection and response (EDR), but specifically for AI.

The Takeaway

The market has gone from "is there a real threat?" to "spend billions to stop it" in under three years. HiddenLayer's new focus includes scanning open-weight models for hidden models inside models — a sign that as AI deployments go mainstream, so does the attack surface. Expect consolidation: large cybersecurity firms like Cisco, Palo Alto Networks, and Check Point often prefer to buy rather than build this tech, and HiddenLayer may find itself a target.

Source: TechCrunch, "HiddenLayer nabs $100M as enterprises rush to secure their AI deployments" (Sept 2, 2026).