Melba Kurman, author, and Hod Lipson, Cornell University associate professor in mechanical and aerospace engineering, are co-authors of "Fabricated: The New World of 3D Printing" (John Wiley & Sons, 2013) and leading voices in the field of 3D printing. They contributed this article to LiveScience's Expert Voices: Op-Ed & Insights as part of their new LiveScience series highlighting issues and developments in 3D-printing technology. If you want to start a fight at a party full of people passionate about 3D printing, just mention technology patents. Immediately, people will stake out their positions and the room will erupt into chaos. Blogger Paul Banwatt sums up the debate nicely as a standoff between those "who believe that patents have held back 3D-printing technology and those who believe that patents have really incentivized innovation." Patents are like people. Some do good things and try to help others. Other patents behave like greedy bureaucrats by hiding behind rules and regulations and getting in the way of forward progress. Just to be clear here, in this article we're not talking about the unresolved, looming battle over pirating or the 3D printing of unauthorized copies of IP (intellectual property)-protected designs. We mean patents on actual 3D-printing processes, tools and materials that are filed by companies that make and sell 3D printers and related technologies.