In the United States, patent reexamination is a process in which a patent which had already been approved is reviewed again. The outcome of the reexamination may be that the patent is deemed fully valid and enforceable. In other cases, the examiner may conclude that the scope of the patent is limited, in which case some of the claims which supported it initially are not valid, or the patent may be invalidated altogether. Patent reexamination can be requested at any time during the life of the patent.
Sometimes the director of the United States Patent and Trade Organization (USPTO) requests a patent reexamination in the interests of new information which may call a patent into question or raise concerns about the validity of prior patents. In other instances, the patentholder or someone to whom the patent has been assigned puts in a request. Likewise, people who have been accused of infringing, as well as members of the general public, can file a request for patent reexamination, although filing fees must be paid.
The process is similar to that of an initial patent examination. The patent is assigned to a patent examiner who is qualified to review patents of that nature. This person determines whether or not the product is original, looks for evidence of earlier works which might disprove the claim that something is patentable, and either confirms or rejects the claim that the patent is proprietary in nature. Notification is provided so that people are aware that a patent examination is underway, which allows challengers to come forward with additional information or documentation which may be relevant to the patent reexamination.
Patents allow companies and individuals to develop new inventions and profit from them exclusively for a set period of time. The patent holder can opt to license the patent, allowing other people to use it. Companies use patents in order to obtain competitive advantage by cornering an area of their industry. Reexaminations may be requested to find out whether a company is really infringing on a patent held by another person, to challenge a patent altogether, and for other reasons.
Patents are what is known as intangible assets. The patent represents ownership of a concept or idea, and is not a physical object which generates income for the patent holder. Valuing such assets can be challenging because it can be difficult to determine the value of a patent over its lifetime. One consideration is the costs which people would be willing to pay to license the patent.