I have following idea:
to add line/command author to DAT file.
I think that this would be a little more exact than copyright - mostly if somebody would be happy that it is known that he is author but he gave up all copyrights.
And more, copyright could be ignored in process of making of pakfile. I think that most people would accept this line rather than copyright. And translations of copyright is mostly Author(s) or something like that.
I'm actually not allowed to give up all rights. Everything I do is automatically copyrighted, and there is nothing I can do about it. (Except voting for politicians willing to change the law, but all but a few seem more occupied with health care, education, police, military and social security for some reason.)
Having both author and copyright seems meaningless, but renaming copyright to author, or adding author and renaming copyright to license, seems like a good idea in principle. There are technical obstacles that someone must find it worth overcoming, though.
Same applies to german law. The original author always holds 'copyright' (more precisely 'Urheberschaft'), while granting usage rights to others (also exclusive rights).