Bilski v. Kappos, 561 U.S. 593 (2010), was a case decided by the Supreme Court of the United States holding that the machine-or-transformation test is not the sole test for determining the patent eligibility of a process, but rather "a useful and important clue, an investigative tool, for determining whether some claimed inventions are processes under § 101." In so doing, the Supreme Court affirmed the rejection of an application for a patent on a method of hedging losses in one segment of the energy industry by making investments in other segments of that industry, on the basis that the abstract investment strategy set forth in the application was not patentable subject matter.