What is yours License police?By Milan Jovanovic on 23/07/18 in
As we are using Envato as the marketplace for selling the product, their licensing policies apply: https://codecanyon.net/licenses/terms/regular
Their policy in general is: one license is per one domain or project.
If your multiple sites are sub-sites of the same domain, and apply to the same project, you can use one license.
If these are installed on different domains, and are different projects, you would need a separate license per each.