Within the context of anational ormultilateral body oflaw, aninvention ispatentable if it meets the relevant legal conditions to be granted apatent. By extension, patentability also refers to the substantive conditions that must be met for a patent to be held valid.
Many national and regional patent offices provide procedures for reconsidering whether or not a given patent is valid after grant. Under theEuropean Patent Convention, any person can file anopposition provided they act promptly after the patent is granted. In the United States, members of the public can initiatereexamination proceedings. Japan provides similar options. In India, the Patent Act provides for a dual opposition system i.e. pre-grant opposition as well as post grant opposition. While a pre-grant opposition may be filed by any person, the post grant opposition may only be filed by a person interested in the field of invention.[2]
Members of the public can also initiatelawsuits in the courts of various nations to have patents declared invalid.
United Kingdom patents can be reviewed by way of anon-binding opinion issued by the Patent Office, or by formal applications for revocation before the Patent Office or the Court. If the patent survives a revocation action, this fact is noted for future reference by way of aCertificate of contested validity.
The fact that an invention is patentable or even patented does not necessarily mean that use of the invention would not alsoinfringe another patent. The first patent in a given area might include a broad claim covering a general inventive concept if there is at that point no relevantprior art. Later, a specific implementation of that concept might be patentable if it is not disclosed in the earlier patent (or any interveningprior art), but nevertheless still falls within the scope of the earlier claim (covering the general concept). This means that the later inventor must obtain a license from the earlier inventor to be able to exploit their invention. At the same time, the earlier inventor might want to obtain a license from the later inventor, particularly if the later invention represents a significant improvement in the implementation of the original broad concept. In this case, the two enter into a cross license.
Thomas Edison's thin carbon filament light bulb was a patentable improvement over the earlier patentedWoodward andEvans thick carbon filament light bulb. Thomas Edison bought the Woodward patent for $5,000 US before he began his development work so that Woodward would not be able to later sue him for patent infringement after Edison became commercially successful.
This section'sfactual accuracy may be compromised due to out-of-date information. The reason given is: It seems that it is no longer correct to state that, under U.S. patent law, only inventors can apply for patents. Companies (or, more generally, legal entities) can also apply for patents. Please help update this article to reflect recent events or newly available information.(October 2024)
UnderUnited States patent law,inventorship is also regarded as a patentability criterion. It is aconstitutional requirement, since the language of the US Constitution authorizes "the exclusive Right to their ... Discoveries" to Inventors only. The most significant implication of this requirement, which makes the US practice different from all other countries, is the fact that only actual people-inventors (and not their employer) can apply for a US patent. For this reason, patent applications filed via thePatent Cooperation Treaty often have two sets of applicants: the physical individuals for the US, and the legal entity (employer) for all other countries.[needs update]
The requirement to list actual human inventors was further confirmed bycase law: "Inventorship is indeed relevant to patentability under 35 U.S.C. § 102(f), and patents have in the past been held unenforceable for failure to correctly name inventors in cases where the named inventors acted in bad faith or with deceptive intent."[3][needs update]
Another difference between the practices of theUnited States Patent and Trademark Office (USPTO) and other patent offices is the requirements fornon-obviousness and forinventive step. Although both requirements have the same purpose to prevent patent issuance for routine improvements/modifications (rather than for true inventions), the practical analyses of these criteria are based on different rules and sometimes result in different outcomes (seeInventive step and non-obviousness for more details).[vague]
Details on patentability in the U.S. can be found in theManual of Patent Examining Procedure or MPEP. This is published by the USPTO and is the reference manual used by bothpatent examiners and patent agents/attorneys.Chapter 2100, in particular, gives a comprehensive overview of the standards for patentability, a discussion of the related case law, and guidance on how to overcome an examiner's rejection of a given set of claims.
In the United States, the patent grant is presumptive, e.g. a patent shall issue unless the patent statutes preclude the grant. In other words, the burden is on the Patent Office to prove why a patent should not be granted.[4] Once a patent issues, it is presumed valid and a court may declare it invalid only on the basis ofclear and convincing evidence.
Terminology in Europe, within the member states of theEuropean Patent Organisation,[5] is slightly different from U.S. terminology. While in the U.S. all patent applications are considered to cover inventions automatically, in Europe a patent application is first submitted to a test whether it covers an invention at all: the first out of four tests ofArticle 52(1)EPC (the other three being novelty, inventive step, and industrial applicability). So an "invention" in European legal terminology is similar to "patentable subject-matter" in the American system. Articles 52-57 of the European Patent Convention are concerned with patentability.[6]
Under the Indian Patent Act (1970), "inventions" are defined as a new product or process involving an inventive step and capable of industrial application.[7] Thus the patentability criteria largely involves novelty, inventive step and industrial application or usability of the invention. In addition, section 3 of the Patent Act, 1970, also provides a list of non-patentable inventions for e.g. inventions that are frivolous or contrary to well established to natural laws.[8]
[The question whether there is a patentable invention] is as fugitive, impalpable, wayward, and vague a phantom as exists in the wholeparaphernalia of legal concepts. It involves, or it should involve, as complete a reconstruction of the art that preceded it as is possible. The test of invention is the originality of the discovery, and discovery depends upon the mental act of conceiving the new combination, for substantially every invention is only a combination. Nothing is more illusory, as nothing is more common, than to assume that this can be measured objectively by the magnitude of the physical readjustments required. Courts never tire, or at least in earlier times they never did, of expatiating upon the freshness of insight which observes a little, but fruitful, change which had theretofore escaped detection by those engaged in the field. When all is said, we are called upon imaginatively to project this act of discovery against ahypostatizedaverage practitioner, acquainted with all that has been published and all that has been publicly sold. If there be an issue more troublesome, or more apt for litigation than this, we are not aware of it. (...)
- US JudgeLearned Hand inHarries v. Air King Prod. Co., 183 F.2d 158, 162 (2d Cir. 1950).[9]
