Free and open-source computer-aided design/Licensing

It would be useful to have a copyright license manager to aid combining components and assemblies that may have different copyleft or commercial licenses, and this would dictate ultimately what copyright license the final item can be released under. Some copyleft licences are incompatible with each other due to conflicting terms, or one overrides other licenses in dictating the terms of the completed artefact.

The 'universal commons' browser should have a feature to filter the contents by license in a hierarchically structure. So objects could be filtered at a high level (i.e. open source, commercial or public domain), medium level (strong copyleft or weak copyleft), down to individual licenses. Users may determine from the outset what level of licensing they would like for their project and have the commons browser only show compatible items.

Some licenses such as weak copyleft - where the item is freely available for use in open-source or commercial projects (but the actual copyright still remains with the creator) - and public domain - where there is no copyright at all - are broadly compatible with any other license.

There is also the possibility of dual licensing or multi-licensing which is sometimes used, where an item may freely used for non-commercial purposes under a copyleft license or alternatively it can be incorporated into a proprietary project using a commercial license but for a fee.