Does referencing a CSS stylesheet with a GPL (or AGPL) license "infect" the server side of a web application?
I've never heard of a stylesheet being licensed under GPL. Be how it may, stylesheets are hardly so complex that they couldn't be rewritten manually from scratch, thus avoiding using other people's work (i.e. being bound by any kind of license).
IANAL.
If your code isn't open-source there's not much point (in my opinion) to open-source something as basic as some frontend CSS. You could always put a comment in the CSS reading:
/* Feel free to use this code */
As a rule of thumb, don't use GPL'ed code or material in closed apps, unless there's a specific licence exception or permission allowing linkage.
If the CSS is GPL the author probably wanted it to be used solely for free software.
Just make your own CSS or ask the author for permission. That way you don't need any lawyers to resolve things for you.
Thanks for the feedback, but I'm interested in the question from an academic/legal perspective, not from a what-should-I-do perspective. I could certainly choose to not use the code, ask them to change the license, etc. But what I don't know is how does a client-side reference to a stylesheet may (or may not) affect the license of server-side code.
In terms of the question from an academic/legal perspective (not a practical one).
You really need to talk to an academic legal person. Many GPL-related issues doesn't have a percedence in court, so some bordler-line issues might me anyones guess.
The Free Software Foundation has on-staff lawyers who advice on GPL related issues.
You can find them here: http://www.fsf.org/
You can forward your question to: [email protected]