Nathan Myhrvold, the Microsoft veteran who founded the patent-trolling giant Intellectual Ventures, is right that patent infringement is rampant among software firms. But in demanding that this infringement stop, Myhrvold isn't just declaring war on what he regards as Silicon Valley's patent-hostile culture. He's declaring war on the laws of mathematics. The legal research required for all software-producing firms to stop infringing patents would cost more than the entire revenue of the software industry. Even if firms were willing to pay the bill, there simply aren't enough patent lawyers to do the work. Firms infringe software patents because they don't have any other choice. [...] Why is software different from real estate? In a new paper, we argue the fundamental difference is a matter of scalability: how much effort it takes to discover who owns an invention—or a piece of land—as the number of patents or land parcels increases. Property rights in land scale well because parcels exist in relatively well-defined locations on a two-dimensional plane. County officials take advantage of this fact to store records in a predictable order (or, more recently, to build databases searchable by geographical location). Geographical locations serve as an "index" for real property claims, so record-keepers can find any specific file quickly no matter how many files there are.
From Ars Technica