Tony Stanco formulated a clear distinction between patents and copyright:

Copyright provides exclusive plenary rights to the owner. Patents provide the owner only with the right to exclude others. I think the distinction was grounded in the fact that it would be hard to conflict with someone else’s copyright in an original work (which usually stood alone), while complex, interrelated processes/machines could easily involve multiple and conflicting patents. As a result, patents are only negative rights and a person’s exploitation of a particular patent in subject to the non existence of conflicting patent(s).

It’s a nice conclusion in a long discussion.