Z:gnu-www-ja-danger-of-software-patents--1e3c9f-The field that's closest to th/en

The field that's closest to that is pharmaceuticals. A few decades ago, there really was one patent per pharmaceutical, at least at any time, because the patent covered the entire chemical formula of that one particular substance. Back then, if you developed a new drug, you could be sure it wasn't already patented by somebody else and you could get the one patent on that drug.