Z:gnu-www-ja-gpl-2.0-faq--d30443-Templates are minor enough tha/en

Templates are minor enough that it is not worth using copyleft to protect them. It is normally harmless to use copyleft on minor works, but templates are a special case, because they are combined with data provided by users of the application and the combination is distributed. So, we recommend that you license your templates under simple permissive terms.