So I’m talking about playing previously Windows-only games on Linux, e.g. via proton.
I don’t know about the libraries etc that are used - is it possible for Microsoft to use some legal voodoo, for example, to suddenly end it all, and make the use of their libraries illegal (if they belong to Microsoft in the first place)?
Or could there be other ways of interference?
Not quite. The ultimate decision was that APIs are copyrightable, but that Google’s use of the copyrighted material was Fair Use.
It would not be unreasonable to suppose that as a matter of precedent, any reimplantation of an API is likely to be Fair Use, but because Fair Use is such a case-by-case thing there may be wiggle room in that.
Hmm, you know, I even looked that up before posting, so I wouldn’t be writing nonsense: https://www.wired.com/insights/2014/05/non-apocalypse-apis-copyright-fair-use/
But yeah, it would be weird for a court to make such a wide-reaching decision, if it doesn’t have to. So, that source probably oversimplified that it’s ‘merely’ an important precedent case…
Yeah as far as I can tell SCOTUS didn’t even rule on the “can APIs be copyrighted” portion of the complaint. That was decided by the Federal Court of Appeals, with SCOTUS declining to weigh in, during the first phase of the case (after this ruling was decided, the case went back to the District Court to decide if the use of the copyrighted API was Fair Use). Then when the District Court decided it was Fair Use, the Court of Appeals overturned it, and then finally SCOTUS went back and declared the original decision correct.
Microsoft was among a number of companies that filed amicus briefs in support of Google’s stance (this may interest you, @[email protected]).
Tangent: when reading up more on this, I discovered that America’s 7th amendment hardcodes $20 as the minimum amount to be guaranteed the right to trial by jury in lawsuits. The idea of hardcoding a specific dollar value in your constitution is just hilarious to me. According to this calculator that’s equivalent to over $700 today; at the time, it meant “moderate-sized lawsuits can be guaranteed a jury, but not very small ones”, but today every single lawsuit is likely to meet that requirement, no matter how small.
How much appetite does Microsoft have for litigation? The Linux community is nothing if not stubborn, and they won’t take this lying down. You’ll definitely have the Free Software Foundation and the Electronic Frontier Foundation involved and they’ll fight it all the way to the Supreme Court.
I genuinely think that in this respect the answer is quite literally none. I think as bad as Microsoft was in the past—and still is in some respects (e.g. workers’ rights and the whole AoE Mobile debacle)—they seem genuinely committed to doing the right thing as far as open source is concerned. I was merely answering with what is possible, not what I think likely.