For the purposes of our criteria, when we use the term “open source” on the website it should be referring to the OSI definition. Keeps it dead simple.
For the purposes of evaluating tools, as a community & team we can use more nuance and we should evaluate software like this from best to worst:
- Copyleft (GPL etc.) software meeting FSF free software definition
- Software meeting OSI open source definition
- FUTO/“Source First”-type software
- Proprietary, source available software
- All other proprietary software
However, as we have always maintained, all five of these software types are acceptable on Privacy Guides.
This is simply the order of preference for the specific factor of “licensing” which we do indeed consider. All other things equal, open source software will always be better than proprietary software. However, there are also many cases where proprietary software is better than open source software for other reasons, and that will tip the scales. That’s unrelated to this conversation though.
PS: The reason I think we should prefer copyleft over open source when evaluating two otherwise identical tools is that I think the FSF is correct that they protect user rights and developer rights better, and therefore should be more stable from a long-term perspective.