Onyx Security

Cybersecurity · AI Governance · Enterprise AI

Funding

Onyx Security raises $113M Series B for AI agent governance platform

The startup is betting that as autonomous agents take over enterprise workflows, someone has to police their every move in real time.

• Onyx Security raised $113 million in a Series B led by Bessemer Venture Partners, with Cyberstarts, TCV, Conviction, FirstMark, Vintage, QuantumLight and G Squared also participating.
• Onyx's 'Secure AI Control Plane' discovers AI agents across an enterprise's browser, endpoint, SaaS and cloud systems and inspects every action before it takes effect.
• The new capital will fund development of Onyx's proprietary models that track agent decision-making and expand its US-focused sales and marketing operations.
• Onyx says it already secures more than 1.1 million AI agents and inspects over 66 million agent sessions in real time for customers including Revolut and other Fortune 500 firms.
• Founded in 2024 by Maxim Bar Kogan, a former Unit 8200 officer and Mixtiles product exec, and Gil Elbaz, a former Nvidia AI architect and Israeli Air Force veteran.
• The round comes just four months after Onyx emerged from stealth with $40 million in prior funding, bringing its total raised to $153 million at an estimated $640 million valuation.
• As enterprises delegate more decisions to autonomous agents with standing access to critical systems, governance and runtime oversight are becoming as essential as the AI itself.