Austin-based HiddenLayer closed a $100 million Series B led by Delta-v Capital, TechCrunch reported on September 2, 2026. Ten Eleven Ventures, Morgan Stanley, Microsoft’s M12, Booz Allen Ventures, and others participated, according to TechCrunch and the company’s PR Newswire statement. CEO and co-founder Chris Sestito said the round lets the company keep building a purpose-built team and platform as agentic AI becomes core to how enterprises operate.
HiddenLayer sells tools that secure agentic, generative, and predictive AI applications across discovery, supply chain security, attack simulation, and runtime protection. TechCrunch said the company has extended those products to cover prompt injection, agent manipulation, and malicious tool use, and likened its runtime security work to endpoint detection and response built for AI. In August 2026 it launched Agent Harness Security, a stand-alone option that uses an agent’s native hook surface to detect and stop prompt injection, data exposure, and unsafe command execution as they happen, per the company statement.
The firm said annual recurring revenue grew more than 10x over the past year and that it signed more than 50 new platform customers across brokerage, banking, insurance, government, pharmaceuticals, and defense, including support for a frontier model provider securing more than 700 million weekly users. Its researchers hold 39 granted patents and 65 pending, the statement said.
HiddenLayer said it will use the capital to deepen Agentic Runtime Security and Agent Harness Security, expand sales and distribution, grow engineering and research, and push into Europe and the wider EMEA region. It recently named Mike Gesnaldo chief revenue officer. The round is another signal that enterprises are treating AI security as its own category rather than a bolt-on to traditional infrastructure tools.
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