A patent has been granted for a method of preventing people using 3D printers to pirate goods.
The broad patent uses a copy-protection system similar to that found on music files, movies and computer games.
This copy management system acts as a digital wrapper around the design files used by 3D printers.
Before a printer starts producing an object, the copy-protection system checks permission has been given to produce it.
3D printers, which typically reproduce objects using partially melted plastic, are rapidly dropping in price, leading many to expect they will be soon found in more and more homes.
To head off the potential piracy caused by so many people having the ability to make almost any object themselves, US firm Intellectual Ventures has come up with a "manufacturing control system" to limit abuse.
Issued on 9 October, the patent describes a way to embed copy controls in 3D design files. These files hold all the measurements a printer needs when it works out how to reproduce an object in plastic.
Files bearing the protection system would check to see that the original creator of the design file was happy for a copy to be produced by looking for a licensing agreement or evidence that a customer had paid the appropriate fee.
The patent said the protection system could apply to 3D printing or other future technologies that use digital design files for painting, tattooing or die casting.
California-based Intellectual Ventures was established by former Microsoft technology boss Nathan Mhyrvold. It now owns and controls about 40,000 technology patents.