It has little to do with "creative output" and more to do with the license surrounding those components you use, and the components your "final product" uses. Y

It has little to do with "creative output" and more to do with the license surrounding those components you use, and the components your "final product" uses. You seem to be insinuating it's ridiculous to apply this sort of "derivative work, by-way-of-library" logic to compilers, but it absolutely happens all the time. It happens especially with compiler-style things, in fact. Just as the most obvious example, several large GPL libraries, parts of GCC such as libgcc, and more, run under the GPL linking exception -- this exception to GPL-licensed libraries means that programs using those libraries directly are not subject to the rules of the GPL, while normally they would be (under the "derivative work" logic). For example, every C program compiled by GCC links against libgcc, which is GPL. But you are not implicitly put under the terms of the GPL, just because you used GCC to compile something, and it happened to use libgcc. libgcc explicitly exempts this use case. So, why does this exception exist, and why is it explicitly stated? Precisely because, just like those "template content libraries" from some random vendor, GCC links your code against components and libraries that have clear licensing terms. The licensing terms of those libraries absolutely impacts the licensing terms of the final, produced work, unless stated otherwise. (Have you ever noticed how even commercial software is required to maintain a copy of the BSD license? Well, it's legally required to, if you use BSD software. It says so, right on the tin.) This isn't some kind of legal 12-dimensional chess, it's a fairly obvious bump you encounter quite quickly. This is obviously especially important for compiler-style things, since in reality, their whole purpose is to generate "derivative works" of all sorts. Guile also has a GPL linking exception for some similar reasons, IIRC. In all honesty, to me, the weird thing about this case isn't that they're making claims about "derivative works" or whatever, with regards to libraries. It's weird to me that they even need to make the argument at all -- most of the time, with a lot of software, the licensing situation surrounding components like this (and how you can use them) is pretty clear. It seems odd it wouldn't be strictly clear already, in a way.