The Wayback Machine - https://web.archive.org/web/20231124065558/https://docs.github.com/en/github-ae@latest/apps/using-github-apps/installing-a-github-app-from-a-third-party

GitHub AE is currently under limited release.

Installing a GitHub App from a third party

You can install GitHub Apps directly from the app owner to use on your personal account or organizations.

You cannot install third-party GitHub Apps on organizations owned by your instance.

For more information about installing GitHub Apps that you own, see "Installing your own GitHub App."