The Patent Statute defines patent eligible subject matter as any new and useful process, machine, manufacture and composition or improvement thereof. 35 U.S.C. § 101. Recently, the Federal Circuit (i.e., the appeals court for all patent matters) decided the case of In Re Bilski which clarifies the types of useful processes that are eligible for patent protection under the Patent Statute.
In In Re Bilski, the Federal Circuit rejected numerous tests that were used in various judicial opinions. The Federal Circuit held that the test to use is the machine-or-transformation test which states that a process is eligible for patent if: “(1) it is tied to a particular machine or apparatus, or (2) it transforms a particular article into a different state or thing.” In Re Bilski, 2007-1130 (Fed. Cir. 2008).
The Federal Circuit expressed two corollaries for the machine-or-transformation test: (1) a process that preempts an entire field is not eligible for patent protection and (2) insignificant post solution activity will not transform an unpatentable principle into a patentable process.