Daily · · Claude · 🌶️🌶️Worth a lookMedium: worth a look Why: A leaked key stops working off your IPs
Claude IP allowlists lock keys to your net
A leaked Claude API key now has fewer places it can run.
Claude Platform’s Nov 5, 2026 release notes add organization IP allowlists in beta, so covered requests from addresses outside your list are refused. You can add up to 1,000 IPv4 or IPv6 addresses or CIDR ranges.
What changed
The allowlist limits where a key or sign-in works, not how long it lives. Anthropic still recommends short key expiration or Workload Identity Federation alongside it. Changes can take up to 15 minutes to apply.
Where it applies
- On Claude Platform (Console) it covers UI access, Messages and related API endpoints, Managed Agents management endpoints, plus Admin and Compliance APIs for that organization.
- On Claude Enterprise it covers browser, desktop, and mobile Claude, Claude Code signed in with a Claude account, Claude in Chrome, Office add-ins, Cowork, and Remote Tools. Blocked Claude Code users see a 403 that the IP isn’t in the organization’s allowed range.
What to do
List every public egress you need (offices, VPN, CI, proxies), keep the “allow admins/owners to reach allowlist settings from any IP” checkbox on so you don’t lock yourself out, then save. Bedrock, Claude Platform on AWS, Google Cloud, and Microsoft Foundry aren’t covered.
Claude Design and Claude in Slack also stay outside the Enterprise list.
Source: Claude docs: IP allowlisting · Claude Platform release notes, Nov 5, 2026