Hi @raspdroid
licensing has been discussed quite widely in some posts
- 3D new library for Mechanical CAD exporting and enclosure design
- Contributing to update of VRML librarys to STEP?
and a Wayne point of view
http://www.mail-archive.com/kicad-developers@lists.launchpad.net/msg16274.html
Query:
What kind of restrictions do I have to expect when I’m using KiCad for my designs?
Wayne reply:
None. I don’t think anyone here believes that if you use our symbols, footprints, and/or 3D models that we own you design. If they do, we have a serious issue.
that point of view, I think, is putting away the problem of distributing the design …
Anyway for 3D mechanical symbols we preferred to clearly state a licensing policy which is giving all the needed freedom and knowledge to the designer 
3D Model-Licencing
Maurice