Startups securing models, agents, and LLM applications: red teaming, runtime guards, and agent identity.
21 companies · ordered by name · no paid placement · About this category
Seoul, South Korea
Seoul-based AI red teaming and guardrail company testing language models, agents, and physical AI systems for exploitable behavior.
Closed a KRW 10 billion Series A led by Samsung Venture Investment, April 2026
Israel
Context firewall for AI agent fleets: discovers agents, continuously vets the skills, plugins, and MCP servers they touch, and blocks what fails.
Emerged from stealth with $50M raised across two seed rounds led by Sequoia and Greenoaks, September 2026
San Francisco, United States
Assurance and insurance company for AI agents: it audits agents against its AIUC-1 standard and writes insurance tied to the audit results.
Raised a $40M Series A led by Ribbit Capital, September 2026
New York, United States
AI safety and security company (formerly ActiveFence) that red teams models and runs guardrails for AI labs and enterprises.
Raised $140M led by Apax Digital Funds, August 2026
Pittsburgh, USA
Frontier-lab red teaming (Shade) and runtime defense (Cygnal) trained on unpublished attacks.
Raised $40M Series A co-led by Wing and Madrona, May 2026
Austin, USA
Model scanner, attack simulation, and runtime firewall for agentic, generative, and predictive AI.
Raised a $100M Series B led by Delta-v Capital, September 2026
Tel Aviv, Israel
Need-to-know access control so Copilots, coding agents, and MCP tools stop oversharing.
Raised $11M to ship need-to-know controls for enterprise AI, March 2025
Tel Aviv, Israel
Discovery, posture, automated red team, and gateway runtime for models and agents.
Published Securing Agentic AI: The Intent Security Framework, March 2026
San Diego, United States
Detection and response for AI agents on employee endpoints: maps what each agent touches, baselines its behavior, and stops the ones that go rogue.
Raised an $8M seed round led by Costanoa Ventures, March 2026
London, United Kingdom
Attacker-style recon and automated red team for models, agents, IDEs, and the systems around them.
Raised $30M Series A led by Album VC, August 2026
Boston, United States
Deepfake voice and voice fraud detection for live calls, analyzing the audio itself to flag cloned voices, vishing, and caller impersonation.
Raised $25M led by Future Ventures, September 2026
Boston, United States
Endpoint sensor that inventories AI agents, MCP servers, and extensions on employee machines and enforces allow, block, or approve policies on their actions.
Emerged from stealth with $100M, including a $75M Series A led by Andreessen Horowitz and Bessemer Venture Partners, July 2026
New York, USA
AI-SPM, agent access control, red team, and AI-DR in one control plane for homegrown and SaaS agents.
Raised $100M Series B led by Evolution Equity Partners, July 2025
Tel Aviv, Israel
Control plane for enterprise AI agents: finds sanctioned and shadow agents, watches what they try to do, and blocks harmful actions before they run.
Raised a $113M Series B led by Bessemer Venture Partners, July 2026
Miami, USA
Inventory, agentic red team, and self-improving runtime guardrails for the agent lifecycle.
Named a 2026 Gartner Cool Vendor in AI Software Security
New York, United States
Runtime security for the AI agents enterprises build themselves, using a sidecar that records and polices agent actions inside the customer's own cloud.
Raised a $25M Series A co-led by Glilot Capital and Sienna Venture Capital, October 2026
New York, USA
MCP gateway plus identity, observability, and threat detection for enterprise agents.
Emerged from stealth with $11M seed from Khosla (Keith Rabois) and Felicis, November 2025
Mountain View, USA
Discover, adversarially test, and kill-switch AI agents and MCP connections in production.
Raised $64M Series A, taking total funding to $85M, June 2026
Menlo Park, USA
Continuous trust tests so enterprise agents stay reliable after they leave the lab.
Raised $17M Series A led by BrightMind Partners, November 2025
Mountain View, USA
Observe, control, and protect employees, models, apps, and agents from one AI security plane.
Raised $58M led by Sound Ventures, January 2026
New York, USA
Agent security that watches the decision, not just the prompt, across SaaS, cloud, and endpoint.
Raised $125M Series C led by Norwest, August 2026
AI security is the newest category here and the easiest to confuse with a booth label. This index maps companies whose primary product secures models, agents, and LLM applications: red teaming, runtime guards, and agent identity.
A general-purpose SAST tool that added an LLM checkbox does not belong. Every entry carries a 2024 to 2026 proof-of-life signal recorded with a source link, and membership is taxonomy from the research pass.
The products here include model and agent red-teaming platforms, runtime prompt and tool-call guards, agent identity and authorization, and LLM-application firewalls. Some target builders shipping agents; others target enterprises that need an inventory of model use.
Generic code scanners and GRC questionnaires about AI policy live in other directories.
Security engineers responsible for LLM and agent rollouts, founders comparing runtime guards versus red-team platforms, and investors who want companies whose main product is AI security rather than an add-on SKU.
Included only when a live company has primary category ai-security. Generic code scanners, GRC AI-policy questionnaires, and PR-diff reviewers live in their own directories. Inclusion is category-based and verification-gated, not paid placement.
Listings are the full live catalog slice for this primary category, sorted alphabetically by name. This is not a scored quality ranking and there is no paid placement. Aevral is a disclosed house listing under the same rules (live, no pin). See /transparency.
21 companies. Catalog last reviewed 2026-08-23. Page copy reviewed 2026-08-23. Next review by 2026-09-23. Ordered by name. No paid placement.