The test was used to determine whether a patent claim was directed entirely to mathematical principles or algorithms, which are not patentable subject matter. The aim of the test was to allow claims that do not attempt to monopolize traditionally patent ineligible subject matter, such as mathematics, thinking, and laws of nature. Though primarily concerned with mathematical algorithms the test has some applicability in all subject matter discussions. Its use peaked in 1994 with In re Schrader. Its use then faded, to be replaced by the now also superseded "useful, concrete, and tangible result" test of In re Alappat. The current legal test for patent eligibility is stated in the Supreme Court's decisions in Bilski v. Kappos, Mayo v. Prometheus, and Alice v. CLS Bank.
