An organization owner must allow forks of private 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."
You can help prevent sensitive information from being exposed by disabling the ability to fork repositories in your organization. For more information, see "Best practices for preventing data leaks in your organization."
- On GitHub.com, navigate to the main page of the repository.
- Under your repository name, click Settings. If you cannot see the "Settings" tab, select the dropdown menu, then click Settings.
- Under "Features", select Allow forking.