Editing Software patent debate (section)

=== ''Mayo'' case ===
In ''[[Mayo v. Prometheus]]'', the Supreme Court invalidated a patent on a diagnostic method, because it non-inventively implemented a natural principle; the Court drew on cases involving computer software and other abstract ideas. In this case, the Court was much more detailed in describing how to recognize a patent-ineligible claim to an abstract idea. The ''Mayo'' methodology has come to dominate patent-eligibility law.  It revived the approach of the [[Parker v. Flook|''Flook'']] and [[Neilson v. Harford|''Neilson'']] cases, which is to treat the underlying principle, idea, or algorithm on which the claimed patent is based as if it were part of the prior art and to make patent eligibility turn on whether the implementation of it is inventive. This led to the "two-step" ''Alice'' test described next.