HiddenLayer, the AI security startup that launched in 2022, has closed a $100 million Series B round led by Delta-v Capital and Ten Eleven Ventures. Morgan Stanley, Microsoft’s venture arm M12, and Booz Allen Hamilton also participated, pushing the company’s total fundraising to roughly $156 million across three rounds.

The company was founded in Austin, Texas, by Chris “Tito” Sestito and other veterans of AI and security roles. It raised a $6 million seed round in July 2022, led by Ten Eleven Ventures and Secure Octane, followed by a $50 million Series A in September 2023 co-led by M12 and Moore Strategic Ventures. IBM Ventures and Capital One Ventures also joined that earlier round.

What HiddenLayer actually does

HiddenLayer’s AISec platform is designed to protect machine learning models from adversarial attacks, prompt injections, model theft, and supply chain compromises. The platform offers runtime detection, model scanning, posture management, and automated attack simulations.

HiddenLayer’s approach doesn’t require access to raw training data or model weights. For enterprises that treat their models like trade secrets, and for government agencies operating in classified environments, that’s a meaningful differentiator.