HiddenLayer Raises $100M Series B to Secure AI Models and Agents
Summary
- • HiddenLayer raises $100M Series B led by Delta-v Capital for AI security
- • AI security market projected at $2.83B in 2026, up 83%, reaching $4.78B next year
- • Startup's ARR grew 10x in past year; customers include DoD and intel community
- • Platform extended to cover prompt injection, agent manipulation, open-source model scanning
Details
$100M Series B Funding Closed
Round led by Delta-v Capital with participation from Ten Eleven Ventures, Morgan Stanley, Microsoft M12, and Booz Allen Hamilton.
ARR Grew Over 10x Year-over-Year
Annual recurring revenue surged more than 10x in the past year to 'tens of millions'; over 90% of growth came from new customers.
AI Security Spend Surging to $2.83B
Gartner estimates $2.83B will be spent on AI security tools in 2026, up 83% from 2025, with spending expected to reach ~$4.78B in 2027.
Previous $50M Series A Raised in 2023
The Austin-based startup raised a $50M Series A three years ago, when AI threats were still largely theoretical with few documented attacks at scale.
Customers Span DoD to Frontier AI Labs
Clients include financial services, large tech firms, the Department of Defense, intelligence community, and reportedly a frontier model provider with 700M+ weekly users.
Platform Extended to Agentic Threat Surface
Existing products — discovery, runtime protection, attack simulation, supply chain security — extended to address prompt injection, agent manipulation, and malicious tool use.
Scans 50 AI File Frameworks for Hidden Models
HiddenLayer parses 50 AI file formats to detect hidden models or models impersonating legitimate ones, targeting risks from open-weight model adoption.
European and EMEA Expansion Planned
New capital will fund expansion into Europe and EMEA alongside broader sales and distribution growth while continuing engineering and research investment.
AI Runtime Security Compared to EDR
CEO Chris Sestito likens AI runtime protection to traditional endpoint detection and response (EDR) solutions — familiar enterprise security architecture applied to AI inference.
Key facts and figures from HiddenLayer's $100M Series B announcement.
What This Means
AI security has rapidly evolved from a theoretical concern into a multi-billion-dollar enterprise priority. HiddenLayer's 10x ARR growth and $100M raise signal that enterprises are now actively budgeting for runtime protection of AI models and agents — not just perimeter defenses. With Gartner projecting AI security spend at nearly $4.78B by next year, this space is maturing fast and drawing interest from large security incumbents like Cisco and Palo Alto Networks, who may prefer acquisition over building these capabilities themselves.