The key patents covering a 3D printing technique called “laser sintering” are set to expire in the next year or two — there are a bunch of them, so they’ll trickle out — and this will radically reduce the price of printing and printers. Laser sintering involves melting a fine powder (usually plastic) in order to fuse it with the powder below and around it, and it’s a technique that produces a very smooth, even finish. The big 3D printer manufacturers, who control the laser sintering patents, have used patent law to lock up the market for devices, and to prevent device-owners from sourcing their powder from third parties. Patent expiry will also open new horizons to the world of hacker/maker printers, like the RepRap and its derivatives. These open-source hardware printers will likewise be able to integrate laser sintering, and to take advantage of a coming explosion in plastic powder suppliers.