Rein Security Raises $25M Series A for AI Agent Runtime Protection
New York and Tel Aviv – October 08, 2026 -- Rein Security has closed a $25 million Series A round, lifting total funding to $35 million as enterprises race to secure autonomous AI agents operating inside production systems. The round was co-led by Glilot Capital and Sienna Venture Capital, with participation from Corner Ventures, Atlacle and RNP Capital Advisors.
Gartner forecasts AI security spending to hit $7.7 billion by 2028
The market for securing AI is projected to reach nearly $4.8 billion in 2027, a 68.7% jump from 2026, before climbing to $7.7 billion in 2028, according to Gartner. Rein's platform uses patented sidecar technology that monitors agent activity at runtime without routing company or customer data through a gateway or proxy, giving security teams visibility into every line of code an agent executes.