another random user sends this excerpt from TorrentFreak:
"Downloading a car – or a pair of sneakers – will be entirely possible, although Ford and Nike won't be particularly happy if people use their designs to do so. A new patent, issued this week by the U.S. Patent & Trademark Office and titled 'Manufacturing control system', describes a system whereby 3D printer-like machines (the patent actually covers additive, subtractive, extrusion, melting, solidification, and other types of manufacturing) will have to obtain authorization before they are allowed to print items requested by the user. In a nutshell, a digital fingerprint of 'restricted items' will be held externally and printers will be required to compare the plans of the item they're being asked to print against those in a database. If there's a match, printing will be disallowed or restricted."