@MartiGruart

Normally, the assumption is that they belong to the same application, but you are not bound to that.  Oftentimes the AI may generate more case types that you really need, and you may opt to consolidate some cases.  If you see case types that are potentially usable by multiple applications, you can opt to do a first import to generate the reusable application (module) and create that case type in that layer.  Then you can do a second import, with the same blueprint, where you create your new application (or extend and existing application) pulling in the case type(s) you want to import into your implementation app.  While doing that, you could import the reusable case type marking it as "From blueprint with inherited" if you want a specialized version, or "Use Existing" if you just want to surface the relationship to another case.

Hope that helps.