Copyright stops reproduction of the artwork itself, whoever copies it and for whatever purpose. Trademark stops confusingly similar use in trade for related goods — even if the copy is not close enough to infringe copyright, or was independently drawn.
Practical implications
- Register the logo as a trademark in your classes; the artwork's copyright rides along automatically.
- Make sure you own the logo first — if a freelancer designed it without a written assignment, the copyright may still be theirs.
- Keep the original design files and dated drafts; they prove authorship when it matters.