Additive manufacturing techniques, colloquially known as 3D printing, will increasingly place pressure on the world’s patent systems in a manner akin to the challenges the copyright systems faced due to digital files. Unlike copyright, digital files themselves do not, under present patent law, constitute the patented invention itself. Under current US law, there should be infringement based on the digital files themselves – so-called digital infringement – if someone sells or offers to sell the file that will ‘print’ the patented invention. Additionally, some commentators have called for mechanisms to protect patent holders directly by permitting claims that are specific to digital files. While such digital infringement protects patent owners, it also risks considerable extraterritorial reach for US patents in terms of liability and damages. The chapter explores this dynamic and offers possible mechanisms for addressing these concerns.