Usual disclaimer: I am not a lawyer — any info below should be treated with caution
I’ve always found the GPL license extremely confusing and ambiguous. MIT, BSD and Apache I get: use it how you like, just don’t expect a warranty and leave the copyright message intact. LGPL, MPL, link to it but if you make any changes you must open source the changed library only.
GPL, however, “infects” all other code it links to once you distribute it, meaning the whole code must be released under GPL. GPL is “free” in the context of freedom not money.
I love the open source movement but can’t help thinking the GPL license doesn’t make the concept of distribution clear enough in the context of web development. I personally will not use any front-end GPL code as there is no precedent set (that I’m aware of) that says whether linking to a script from a HTML page and having it download into users’ browsers constitutes distribution.
Server-side is a different matter. If I work for Acme Corp and installed a modified version of WordPress on a company server it’s certain that no distribution has taken place as internal use is allowed.
However, if I don’t work for Acme Corp and they employ me as a freelancer to make a WordPress (or other GPL code) site then I believe, unless I have a contract that states otherwise, I am distributing the GPL code to them even if it’s only distributed once. Therefore, any modifications to the site, such as the Acme Corp custom theme, would need to be released under GPL. The reason I say “unless I have a contract that states otherwise” is because in the UK, US, etc copyright falls with the creator by default. So, we’d need it in writing that I am creating this on behalf of the client to avoid the work constituting as distribution (or else agree to open source everything which very few clients would agree to). So this would be one of those laws that’s broken all the time — but it’s a law broken no less.
If I’m right (and feel free to state if/why I’m not), this is a lose-lose situation for me as a freelancer. I prefer to retain copyright to all design and code and license it to the client in case there are elements I want to reuse in other projects. So I either give up copyright or have to open source a site (few clients, if any, would agree to this).
What do you think? I’ve spent some time Googling this as I tend to be very cautious with all things legal but find anything GPL-related frustratingly ambiguous.
As it happens I don’t really use WordPress and to err on the side of caution don’t use any GPL code at all in terms of JavaScript and PHP. I appreciate the server runs GPL software, e.g. MySQL, but this is definitely not distribution.