# Rein Security

> Runtime security platform that monitors and governs enterprise AI-agent behavior.

## Why it is interesting

Rein is attacking the security layer created when autonomous agents are allowed to read data, call APIs and change business systems without continuous human review.

## Profile

- **Latest funding:** Series A — $25M (October 8, 2026)
- **Latest known valuation:** Not publicly disclosed
- **Total disclosed equity funding:** $25M
- **Stage:** series-a
- **Status:** private
- **Industries:** cybersecurity, ai-ml, enterprise-saas
- **Coverage:** full
- **Last updated:** 2026-10-10
- **Latest funding investors:** Glilot Capital, Sienna Venture Capital, Corner Ventures, Atlacle, RNP Capital Advisors

## Key facts

- $25M Series A co-led by Glilot Capital and Sienna Venture Capital in October 2026
- $35M total disclosed funding
- Company says revenue grew 8x and customer count 5x since its January 2026 launch
- Named customers include Lemonade and Dun & Bradstreet

## Funding history

- Series A · $25M · October 8, 2026
  Source: https://reinsec.io/blog/series-a/

## Investors in our directory

- https://venturecapitaltracker.com/fund/glilot-capital
- https://venturecapitaltracker.com/fund/sienna-venture-capital
- https://venturecapitaltracker.com/fund/corner-ventures

## Related articles

- https://venturecapitaltracker.com/rein-security-25m-series-a-ai-agent-runtime-security

**By:** [Venture Capital Tracker](https://venturecapitaltracker.com/editorial-policy)
**Last updated:** October 10, 2026

**Editorial note:** AI tools assisted with research, structure, or drafting. Venture Capital Tracker retains human editorial responsibility for factual accuracy, relevance, and source quality before publication.

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Source: https://venturecapitaltracker.com/startup/rein-security