All open source licenses are permissive. They give you permission in advance to use the software for any purpose, to improve the software any way you wish and to share the software with whoever you want. They are the opposite of proprietary licenses, which place restrictions on each of these freedoms. Any license with restrictions would not be considered OSD compliant.

All open source licenses include conditions. Some relate to attribution. Some relate to reciprocal licensing. None of them restrict how you can use, improve and share the software, although you must comply with the conditions in order to do so. Some people consider some conditions so onerous they rise to the level of restrictions, but the consensus of the community has been they are wrong.

Today’s licensing games are thus mainly about testing where the accumulated burden of conditions is effectively a restriction – “constructive restriction”. There’s certainly a line where that would become true – for example, where the conditions associated with deploying the software as a cloud service are so hard to comply with that the software is effectively unusable in that field of use.

The OSD doesn’t include much to help with this so it’s contentious every time and sometimes leads to sophistry. This is probably the area where the Open Source Initiative needs to do the most work to modernise the license approval process.