Company profile
Arcjet
Runtime security platform for AI agents, extended to coding agents on developer endpoints Oct 8, 2026. $3.6M seed led by a16z (Sep 2024); valuation Undisclosed.
- Status
- PrivateResearch map: Seed / private · San Francisco · founded 2023 by David Mytton · $3.6M seed led by a16z (Sep 2024)
- Valuation
- Undisclosed
- Latest funding
- Undisclosed
- Website
- arcjet.com
- CyberMerge Index
- #6 · score 74 Oct 8, 2026
- Last updated
Categories
Funding & valuation
Funding: Undisclosed — no round recorded in the CyberMerge Funding Tracker.
Research map notes
- Research map · Agentic Endpoint Security · Undisclosed $3.6M seed led by Zane Lackey at Andreessen Horowitz with Seedcamp (Sep 10, 2024; Arcjet blog). Valuation Undisclosed. Source (recorded Oct 8, 2026)
Rankings
- CyberMerge Index · Oct 8, 2026 #6 · score 74. Launch (same-day): Runtime Security for Coding Agents extends Arcjet's agent policies to Claude Code, OpenAI Codex, Cursor and GitHub Copilot, with an endpoint agent to find unmanaged coding agents and an audit log of actions and decisions. Arcjet says it runs in 500+… Source Daily momentum, not market cap.
Competitors
Same-category peers from CyberMerge Research maps, Startup Radar and What's The Use tags.
- Palo Alto NetworksPublic · PANWEnterprise security platform spanning NGFW, SASE, CNAPP, and Cortex SOC analytics.
- MicrosoftPublic · MSFTIdentity, endpoint, cloud, email, and SOC tooling integrated across Microsoft 365 and Azure.
- CrowdStrikePublic · CRWDCloud-native endpoint and identity security with managed hunting and XDR.
- XoperoStatus not recordedPolish data-protection vendor that closed Vigil Guard to add AIDR / AI governance on top of backup and DR.
- Vigil GuardAcquired by XoperoMonitors and secures AI interactions with prompt-injection detection, granular AI-agent control, and…
- NeoPrivateReal-time control layer that inventories agents, MCP servers, browser AI, and agentic software and enforces…
- ArmadinPrivateAI-native offensive security: autonomous agent swarms chain low-severity weaknesses into validated kill…
- OX SecurityPrivateAI-native AppSec from prompt to runtime: ASPM/PBOM, VibeSec for AI-generated code, plus OX Cloud CNAPP with…
- Rein SecurityPrivateRuntime security from inside the app: baselines how production code and AI agents actually execute, then…
- RecoPrivateSaaS and AI-agent context graph plus browser/network discovery and prompt/tool-call controls — securing…
- IslandPrivateEnterprise browser plus AI Protect: prompts, tool calls, Island MCP Gateway — agentic control plane for…
- Eve SecurityPrivateAgentic AI runtime security (EveGuard): Agent-in-the-Loop observability, intent/data policy enforcement, and…
Related CyberMerge stories
- Rein’s $25M says agent security gets bought where the code already runs. Oct 8, 2026 · Funding
On the desk
- Today's Deals · Product · Oct 8, 2026 Arcjet puts runtime policy on Claude Code, Codex, Cursor and Copilot. Arcjet press release (PR Newswire), Oct 8, 2026
Figures appear only as recorded in CyberMerge data, with source and date. “Undisclosed” means no published figure in our data. Editorial, not investment advice. Last updated . Spot an error? Tell the desk.