Topic on Help talk:Tabular data

"license": "CC0-1.0+", which means the data can be used under the CC0 version 1.0, or (at your option) any later version

Or later version is superfluous for CC0-1.0, which has no conditions at all, let alone any pertinent to license versions. The "+" notation and "or (at your option) any later version" is advisable for A/L/GPLv2/3 because those licenses aren't compatible with later versions of themselves without such additional permission. There's no reason to copy these when implementing other licenses. Suggest instead:

"license": "CC0-1.0", which means the data has been released under CC0 version 1.0

@Mike Linksvayer, thanks. IANAL, so I put it there because I suspected that it would be possible for CC to create another version of CC0 license in case for some weird legal reason CC0-1.0 would not cover some usecase, and so having the "+" would ensure that even if data under CC0-1.0 doesn't cover that usecase, the data can be automatically re-licensed under the better license version. I will poke our legal about this. Do you think having that "+" sign would ever hurt?

@Yurik not sure how taking material contributed under "CC0-1.0+" as available under hypothetical CC0-2.0 would hold up; probably depends on what "some usecase" is. Generally I wouldn't suggest adding something intended to be legally meaningful without poking your legal first. :-) Note that Wikidata does not purport to use "+".

Hmm, perhaps we should change it then. Thanks for the heads up! I will poke our legal, and I think we should make it the same as WD.