Viva Moffat has written an interesting paper on the problems resulting from overlapping intellectual property protections -
"The interactions between the three federal schemes of intellectual property protection – copyright, patent, and trademark – have often been overlooked. This article addresses some of the issues raised by the overlaps between these areas of law and concludes that the availability of more than one form of protection for certain creative or inventive works creates problems in many circumstances; that those problems have not been considered fully by policymakers or courts; and that overlapping protection interferes with the benefits meant to flow to the public."