Is the copyright mentioned in GPL v3 used just for the sake of defining the word? (It's not copyrighted, but the word encompasses the same actions that would violate the copyright if it was copyrighted.)
To “propagate” a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well.