From iionly:

"I'm fully aware that the GPL allows the free use, modification and re-distribution of code licensed under it. But the GPL also restricts changing of the license without consents of the copyright holder and especially requires to include (and moreover not to remove or alter) the copyright references included in the original version when re-distributing the unchanged or a modified version of the code. This should prevent anyone from including the code in any closed-source projects or violate the GPL in any other way. If the copyright information (and either the license itself or a link to it) is always included no one can say "I didn't know that this or that is not allowed."

Can't you include a README.txt to any downloaded zip archive that contains copyright information and any other useful hints? This seems the easiest solution to me."

Reply

"Yes, I'm aware of the need of reproducing the license with any copy of the material, and what i was planning to do was similar to what you are saying. I would add a licence comment on top of every FILE that is generated, rather than as a separate file in the ZIP. People are also able to get a single .php file instead of the whole ZIP, so that makes it more pervasive 😉"