An organization owner must allow forks of private and internal repositories on the organization level before you can allow or disallow forks for a specific repository. For more information, see "Managing the forking policy for your organization."
Note: Internal repositories are available for organizations that are part of an enterprise account. For more information, see "About repositories."
- On GitHub.com, navigate to the main page of the repository.
- Under your repository name, click Settings.
- Under "Features", select Allow forking.