Rein Security Closes $25M to Secure AI Agents
Rein Security raised $25M Series A led by Glilot Capital and Sienna Venture Capital to secure enterprise AI agents against adversarial threats.
The big picture: New York- and Tel Aviv-based Rein Security has closed a $25 million Series A funding round, co-led by Glilot Capital and Sienna Venture Capital, to advance its agentic security platform.
Why it matters:
- AI adoption outpaces security: Despite AI agents being deployed in 95% of companies, according to IDC, there is a significant gap in visible security, leaving enterprises vulnerable to adversarial AI agents and prompt injection attacks.
- Growing market demand: The market for securing AI is projected to reach nearly $4.8 billion in 2027 and $7.7 billion by 2028, indicating a critical and rapidly expanding need for specialized security solutions.
- Real-world vulnerabilities: Rein Security’s research has demonstrated how AI shopping agents can compromise major retailers and how onboarding agents can be manipulated by prompt injections, highlighting the immediate risks to enterprise operations.
How it works:
- Patented sidecar technology: Rein Security’s platform is built on a patented sidecar architecture, allowing it to run alongside main applications to handle security tasks without altering core code.
- Runtime monitoring: The software operates at runtime, enabling continuous monitoring of AI agents as they execute, providing real-time defense against malicious activities.
- Secures the agent supply chain: Rein’s platform secures the entire agent supply chain without routing sensitive company or customer data through external gateways or proxies, maintaining data privacy and integrity.
The catch: While the market for AI security is rapidly expanding, it is also becoming increasingly crowded with new entrants. Rein Security will need to differentiate its patented sidecar technology and demonstrate clear ROI to capture significant market share amidst evolving threats and a competitive landscape, especially as larger cybersecurity vendors integrate AI-specific features into their broader offerings.
Key Facts
- Company: Rein Security
- Amount: $25M
- Round: Series A
- Investors: Glilot Capital and Sienna Venture Capital (co-lead), Corner Ventures, Atlacle, RNP Capital Advisors
- Founders: Matan Bar-Efrat, Netanel Rubin
- Sector: AI Agent Security
- Headquarters: New York, US; Tel Aviv, Israel
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