Software patents under U.S. patent law
In the 1950s, 1960s, and 1970s, the United States Patent and Trademark Office (PTO) did not grant a patent if the invention used a calculation made by a computer. The PTO's rationale was that patents could only be granted to processes, machines, articles of manufacture, and compositions of matter; patents could not be granted to scientific truths or mathematical expressions of it. Since the PTO viewed computer programs and inventions containing or relating to computer programs as mathematical algorithms, and not processes or machines, they were therefore not patentable. This view was upheld by the U.S. Supreme Court in Gottschalk v. Benson (1968) and Parker v. Flook (1975).
In the 1981 case of Diamond v. Diehr, the U.S. Supreme Court ordered the PTO to grant a patent on an invention, even though a substantial part of the invention consisted of a computer program which used well-known formulae for calculating the time when rubber was cured and the mold could be opened. The Supreme Court stated that in this case, the invention was not merely a mathematical algorithm, but a process for molding rubber, which was therefore patentable.
After this point, more patents on software began to be granted, albeit with conflicting and confusing results. The Federal Circuit attempted to clarify the rules; requiring that the computer program must have a practical application.
The Clinton administration appointed Bruce Lehman as Commissioner of the Patent and Trademark Office in 1994. Unlike his predecessors, Lehman was not a patent lawyer but the chief lobbyist for the Software Publishing Industry. In 1995, the PTO established some broad guidelines for examining and issuing software patents. The PTO interpreted the courts as requiring the PTO to grant software patents in a broad variety of circumstances. Note, that although the U.S. Congress has never legislated specifically that software is patentable, the broad description of patentable subject in the Patent Act of 1952 and the failure of Congress to change the law after the court decisions allowing software patents, has been interpreted as an indication of Congressional intent.
Another effect of this change was that as courts began to permit software invention to be patentable, other courts also began restricting the use of copyright law to obtain patent-like protection of software.
See Software patent debate for a discussion as to whether software should be subject to patents.
Landmark decisions
- Diamond v. Diehr
- State Street decision
See also
