A software patent is a patent on a piece of software, such as a computer program, libraries, user interface, or algorithm.
Background
A patent is a set of exclusionary rights granted by a state to a patent holder for a limited period of time, usually 20 years. These rights are granted to patent applicants in exchange for their disclosure of the inventions. Once a patent is granted in a given country, no person may make, use, sell or import/export the claimed invention in that country without the permission of the patent holder. Permission, where granted, is typically in the form of a license which conditions are set by the patent owner: it may be free or in return for a royalty payment or lump sum fee.
Patents are territorial in nature. To obtain a patent, inventors must file patent applications in each and every country in which they want a patent. For example, separate applications must be filed in Japan, China, the United States and India if the applicant wishes to obtain patents in those countries. However, some regional offices exist, such as the European Patent Office (EPO), which act as supranational bodies with the power to grant patents which can then be brought into effect in the member states, and an international procedure also exists for filing a single international application under the Patent Cooperation Treaty (PCT), which can then give rise to patent protection in most countries.
These different countries and regional offices have different standards for granting patents. This is particularly true of software or computer-implemented inventions, especially where the software is implementing a business method.
Early example of a software patent
On 21 May 1962, a British patent application entitled "A Computer Arranged for the Automatic Solution of Linear Programming Problems" was filed. The invention was concerned with efficient memory management for the simplex algorithm, and could be implemented by purely software means. The patent struggled to establish that it represented a 'vendible product'. "The focus of attention shifted to look at the relationship between the [unpatentable] computer program and the [potentially patentable] programmed computer". The patent was granted on August 17, 1966, and seems to be one of the first software patents, establishing the principle that the computer program itself was unpatentable and therefore covered by copyright law, while the computer program embedded in hardware was potentially patentable.
Jurisdictions
Most countries place some limits on the patenting of inventions involving software, but there is no one legal definition of a software patent. For example, U.S. patent law excludes "abstract ideas", and this has been used to refuse some patents involving software. In Europe, "computer programs as such" are excluded from patentability, thus European Patent Office policy is consequently that a program for a computer is not patentable if it does not have the potential to cause a "technical effect" which is by now understood as a material effect (a "transformation of nature"). Substantive law regarding the patentability of software and computer-implemented inventions, and case law interpreting the legal provisions, are different under different jurisdictions.
Software patents under multilateral treaties:
Software patents under TRIPs Agreement
Software patents under the European Patent Convention
Computer programs and the Patent Cooperation Treaty
Software patents under national laws:
Software patents under United States patent law
Software patents under United Kingdom patent law
Australia
In Australia, there is no particular exclusion for patents relating to software. The subject matter of an invention is patentable in Australia, if it is a manner of manufacture within the meaning of section 6 of the Statute of Monopolies. The High Court of Australia has refrained from ruling on the precise definition of manner of manufacture stating that any such attempt is bound to fail for the policy reason of encouraging national development in fields that may be unpredictable. In assessing whether an invention is a manner of manufacture, the High Court has relied on the inquiry of whether the subject of the claims defining the invention has as its end result an artificially created state of affairs.