Just like Napster was to copyright law, the growing prevalence of 3D printing in addition to the easy sharing of computer-aided design (CAD) files is becoming a hot debate topic in the patent law realm.
With a 3D printer, anyone can download a CAD file that would instruct the 3D printer to make the physical, three-dimensional object, which may comprise patented elements. The problem is that it is much more difficult to determine who is printing patented inventions because 3D printers are becoming widely dispersed and do not leave a digital footprint to be traced.
Alternatively, patent owners could go after the facilitators of the infringement, such as potential inducers of patent infringement: those who provided the CAD files of the patented device and/or instructions.
However, the biggest hurdle is that inducement of patent infringement requires actual knowledge of the relevant patent, whereas for music, it is presumed that everyone knows songs are copyrighted.
Another difference between 3D printing and music copyright is that for copyright, the digital files themselves infringe, but for patent law, only the physical 3D printed object infringes. It seems likely that courts and/or Congress will eventually have to address these issues, ironically rooted from an ingenious patented device.