Disabling unauthenticated sign-ups

If you're using built-in authentication, you can block unauthenticated people from being able to create an account.

All GitHub docs are open source. See something that's wrong or unclear? Submit a pull request.

From a GitHub Enterprise Server administrative account, click in the upper-right corner of any page.
In the left sidebar, click Management Console.
In the left sidebar, click Privacy.
Unselect Enable sign-up.
Under the left sidebar, click Save settings.
Wait for the configuration run to complete.