I don't understand why trademark keeps coming into this discussion. To me, this looks like a very clear case of derivative works, which has nothing to do with trademark law.
From the very link you posted: A “derivative work” is a work based upon one or more preexisting works, such as a translation, musical arrangement, dramatization, fictionalization, motion picture version, sound recording, art reproduction, abridgment, condensation, or any other form in which a work may be recast, transformed, or adapted. A work consisting of editorial revisions, annotations, elaborations, or other modifications, which, as a whole, represent an original work of authorship, is a “derivative work”.
How is a piece drawn based on the works in a copyrighted reference sheet anything other than an "elaboration" of that work? That, in and of itself, makes the work a derivative work, and nothing in that law requires anything to do with trademark. It's also not "work for hire" (which I agree also has nothing to do with this discussion, as it's a really high bar to reach "work for hire" and isn't likely it ever really comes up in personal commissions).
When I used to run conventions, we had to turn away artists entries to art shows more than once whose are was clearly derivative of commercial works. It didn't matter if there was a trademark associated with that work or not, if it's clearly derived from some other piece of work, it's a no-go.
no subject
From the very link you posted:
A “derivative work” is a work based upon one or more preexisting works, such as a translation, musical arrangement, dramatization, fictionalization, motion picture version, sound recording, art reproduction, abridgment, condensation, or any other form in which a work may be recast, transformed, or adapted. A work consisting of editorial revisions, annotations, elaborations, or other modifications, which, as a whole, represent an original work of authorship, is a “derivative work”.
How is a piece drawn based on the works in a copyrighted reference sheet anything other than an "elaboration" of that work? That, in and of itself, makes the work a derivative work, and nothing in that law requires anything to do with trademark. It's also not "work for hire" (which I agree also has nothing to do with this discussion, as it's a really high bar to reach "work for hire" and isn't likely it ever really comes up in personal commissions).
When I used to run conventions, we had to turn away artists entries to art shows more than once whose are was clearly derivative of commercial works. It didn't matter if there was a trademark associated with that work or not, if it's clearly derived from some other piece of work, it's a no-go.