I wonder whether there are implications with other legal systems, such as law in countries of the european union, where also different legal traditions with regards to copyright exist.
I think I once saw an open source, copy-left license for the EU. But never one in the spirit of BSD/MIT/Apache.
We had some very valuable, indirect feedback on Blue Oak from lawyers qualified elsewhere. But not enough. I'd be very interested in inviting specialists from other systems to comment, publicly and privately. Moral rights in their various forms. Differing rules on warranty and damages exclusion enforcement. Things I don't know to ask about.
As for licenses of European origin, someone already mentioned EUPL. I'd add https://opensource.org/licenses/CECILL-2.1. I'm likely forgetting at least one.
To end on a happy note, I'd point out that plainer language can actually help jurisdictional portability. Compare the copyright and patent sections of Blue Oak and Apache 2.0, for example. Apache 2.0 takes the typical US legal approach of listing out the exclusive rights of copyright holders, and the actions constituting infringement of a patent, under US copyright and patent statutes. Apache 2.0 does not specify US governing law, but speaks in terms of US law. Blue Oak doesn't list out statutory verbs. It identifies the sets, rather than their specific elements.
But it is a minefield anyway, so just use the ISC license.
Perhaps this was the EUPL¹. As someone who works for a company that has occasionally been forced to use it for a contract, I'm pretty sure people don't choose it. Every time it has come up in a talk about a project, you have to answer basic questions about it :/
> But never one in the spirit of BSD/MIT/Apache
Nor me, but I've seen people mention the idea a few times in conversations about patents normally.
1. https://en.wikipedia.org/wiki/European_Union_Public_Licence