Michel wrote: ↑Wed Mar 03, 2021 10:53 am
My idea is that "the right to distribute something" is not something that is acquired once and then kept forever. You can lose the right to distribute something.
If you accept that FF2 is a covered work then the distribution of it is a violation of the GPL-3 license attached to SF. Hence you can no longer legally accept this GPL-3 licence. So you cannot distribute SF and hence you can also not distribute FF2.
OK, so you rely on:
8. Termination.
You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11).
and you argue that, if a zip file with SF and an NNUE net is indeed a "work based on SF" (and thus a covered work), and the zip file is distributed without the NNUE net being GPL'd (condition 5 c) as applied to the zip file as covered work), then - because of section 8 - there is no permission anymore to distribute the covered work SF under the conditions 5 a) to d).
In this case, the "aggregate" language still seems to be devoid of meaning:
A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.
The zip file as covered work is not part of any aggregate or non-aggregate compilation.
What if I distribute SF together with a non-GPL engine in a zip file? I guess that would still be a "derived work", so this zip file as an "entire work" would have to be fully licensed under the GPLv3. But that is probably not the intention of the GPLv3. Whatever the drafters had in mind exactly, it seems they did not succeed in expressing it in words. Covered work, entire work, compilation/aggregate, the various concepts are all over the place and don't quite add up.
Even if the zip file with SF and the NNUE net is indeed a "covered work", there is still the counterargument that the GPLv3 on SF expressly allows me to distribute the zip file via "covered work = SF" even if it does not via "covered work = zip file". So I can attack your argument based on section 8 in the same way as you attack my argument based on section 5.