Licensing Edgecases

August 13, 2018

While I’m not a lawyer – and I’m definitely not your lawyer – licensing questions are on my plate these days. As I’ve been digging into one, I’ve come across what looks like a strange edge case in GPL licensing compliance that I’ve been trying to understand. Unfortunately it looks like it’s one of those Affero-style, unforeseen edge cases that (as far as I can find…) nobody’s tested legally yet.
I spent some time trying to understand how the definition of “linking” applies in projects where, say, different parts of the codebase use disparate, potentially conflicting open source licenses, but all the code is interpreted. I’m relatively new to this area, but generally speaking outside of copying and pasting, “linking” appears to be the critical threshold for whether or not the obligations imposed by the GPL kick in and I don’t understand what that means for, say, Javascript or Python.
I suppose I shouldn’t be surprised by this, but it’s strange to me how completely the GPL seems to be anchored in early Unix architectural conventions. Per the GPL FAQ, unless we’re talking about libraries “designed for the interpreter”, interpreted code is basically data. Using libraries counts as linking, but in the eyes of the GPL any amount of interpreted code is just a big, complicated config file that tells the interpreter how to run.
At a glance this seems reasonable but it seems like a pretty strange position for the FSF to take, particularly given how much code in the world is interpreted, at some level, by something. And honestly: what’s an interpreter?
The text of the license and the interpretation proposed in the FAQ both suggest that as long as all the information that a program relies on to run is contained in the input stream of an interpreter, the GPL – and if their argument sticks, other open source licenses – simply… doesn’t apply. And I can’t find any other major free or open-source licenses that address this question at all.
It just seems like such a weird place for an oversight. And given the often-adversarial nature of these discussions, given the stakes, there’s no way I’m the only person who’s ever noticed this. You have to suspect that somewhere in the world some jackass with a very expensive briefcase has an untested legal brief warmed up and ready to go arguing that a CPU’s microcode is an “interpreter” and therefore the GPL is functionally meaningless.
Whatever your preferred license of choice, that really doesn’t seem like a place we want to end up; while this interpretation may be technically correct it’s also very-obviously a bad-faith interpretation of both the intent of the GPL and that of the authors in choosing it.
The position I’ve taken at work is that “are we technically allowed to do this” is a much, much less important question than “are we acting, and seen to be acting, as good citizens of the larger Open Source community”. So while the strict legalities might be blurry, seeing the right thing to do is simple: we treat the integration of interpreted code and codebases the same way we’d treat C/C++ linking, respecting the author’s intent and the spirit of the license.
Still, it seems like something the next generation of free and open-source software licenses should explicitly address.