Estoppel is a judicial device in common law legal systems whereby a court may prevent or "estop" a person from making assertions or from going back on his or her word; the person being sanctioned is "estopped". Estoppel may prevent someone from bringing a particular claim. Legal doctrines of estoppel are based in both common law and equity. It is also a concept in international law.
Patent infringement is the commission of a prohibited act with respect to a patented invention without permission from the patent holder. Permission may typically be granted in the form of a license. The definition of patent infringement may vary by jurisdiction, but it typically includes using or selling the patented invention. In many countries, a use is required to be commercial to constitute patent infringement.
Novelty is a requirement for a patent claim to be patentable. An invention is not new and therefore not patentable if it was known to the public before the filing date of the patent application, or before its date of priority if the applicant claims priority of an earlier patent application. The purpose of the novelty requirement is to prevent prior art from being patented again.
The doctrine of equivalents is a legal rule in many of the world's patent systems that allows a court to hold a party liable for patent infringement even though the infringing device or process does not fall within the literal scope of a patent claim, but nevertheless is equivalent to the claimed invention. U.S. Judge Learned Hand has described its purpose as being "to temper unsparing logic and prevent an infringer from stealing the benefit of the invention".
The inventive step and non-obviousness reflect a general patentability requirement present in most patent laws, according to which an invention should be sufficiently inventive—i.e., non-obvious—in order to be patented. In other words, "[the] nonobviousness principle asks whether the invention is an adequate distance beyond or above the state of the art".
The doctrine of assignor estoppel is a doctrine of United States patent law barring a patent's seller (assignor) from attacking the patent's validity in subsequent patent infringement litigation. The doctrine is based on the doctrine of legal estoppel, which prohibits a grantor from challenging the validity of his/her/its grant.
Prosecution history estoppel, also known as file-wrapper estoppel, is a term used to indicate that a person who has filed a patent application, and then makes narrowing amendments to the application to accommodate the patent law, may be precluded from invoking the doctrine of equivalents to broaden the scope of their claims to cover subject matter ceded by the amendments. Although primarily a U.S. term, questions of whether, or the extent to which the prosecution history should be relevant for determining the extent of protection of a patent also arise outside the U.S.
The exhaustion doctrine, also referred to as the first sale doctrine, is a U.S. common law patent doctrine that limits the extent to which patent holders can control an individual article of a patented product after a so-called authorized sale. Under the doctrine, once an authorized sale of a patented article occurs, the patent holder's exclusive rights to control the use and sale of that article are said to be "exhausted," and the purchaser is free to use or resell that article without further restraint from patent law. However, under the repair and reconstruction doctrine, the patent owner retains the right to exclude purchasers of the articles from making the patented invention anew, unless it is specifically authorized by the patentee to do so.
Japanese patent law is based on the first-to-file principle and is mainly given force by the Patent Act of Japan. Article 2 defines an invention as "the highly advanced creation of technical ideas utilizing the law of nature".
Graham v. John Deere Co., 383 U.S. 1 (1966), was a case in which the United States Supreme Court clarified the nonobviousness requirement in United States patent law, set forth in 35 U.S.C. § 103.
Canadian patent law is the legal system regulating the granting of patents for inventions within Canada, and the enforcement of these rights in Canada.
British Leyland Motor Corp. v Armstrong Patents Co. is a 1986 decision of the House of Lords concerning the doctrine of non-derogation from grants. This doctrine is comparable to, but somewhat broader than, the doctrine of legal estoppel, assignor estoppel, or estoppel by deed in U.S. law. Under the doctrine of non-derogation from grants, a seller of realty or goods is not permitted to take any action that would lessen the value to the buyer of the thing sold.
The doctrine of non-derogation from grants is a principle of the law of England and Wales. As the House of Lords explained in British Leyland Motor Corp. v. Armstrong Patents Co., it states that a seller of realty or goods is not permitted to take any action that will lessen the value to the buyer of the thing sold.
Aro Manufacturing Co. v. Convertible Top Replacement Co., 365 U.S. 336 (1961), is a United States Supreme Court case in which the Court redefined the U.S. patent law doctrine of repair and reconstruction. The decision is sometimes referred to as Aro I because several years later the Supreme Court readdressed the same issues in a second case in 1964 involving the same parties—Aro II.
Patent law in modern mainland China began with the promulgation of the Patent Law of the People's Republic of China, in 1984. In 1985, China acceded to the Paris Convention for the Protection of Industrial Property, followed by the Patent Cooperation Treaty in 1994. When China joined the World Trade Organization (WTO) in 2001, it became a member of the TRIPS agreement.
Motion Picture Patents Co. v. Universal Film Mfg. Co., 243 U.S. 502 (1917), is United States Supreme Court decision that is notable as an early example of the patent misuse doctrine. It held that, because a patent grant is limited to the invention described in the claims of the patent, the patent law does not empower the patent owner, by notices attached to the patented article, to extend the scope of the patent monopoly by restricting the use of the patented article to materials necessary for their operation but forming no part of the patented invention, or to place downstream restrictions on the articles making them subject to conditions as to use. The decision overruled The Button-Fastener Case, and Henry v. A.B. Dick Co., which had held such restrictive notices effective and enforceable.
The Mercoid cases—Mercoid Corp. v. Mid-Continent Investment Co., 320 U.S. 661 (1944), and Mercoid Corp. v. Minneapolis-Honeywell Regulator Co., 320 U.S. 680 (1944)—are 1944 patent tie-in misuse and antitrust decisions of the United States Supreme Court. These companion cases are said to have reached the "high-water mark of the patent misuse doctrine." The Court substantially limited the contributory infringement doctrine by holding unlawful tie-ins of "non-staple" unpatented articles that were specially adapted only for use in practicing a patent, and the Court observed: "The result of this decision, together with those which have preceded it, is to limit substantially the doctrine of contributory infringement. What residuum may be left we need not stop to consider." The Court also suggested that an attempt to extend the reach of a patent beyond its claims could or would violate the antitrust laws: "The legality of any attempt to bring unpatented goods within the protection of the patent is measured by the antitrust laws, not by the patent law."
United States v. Westinghouse Electric Corp., 648 F.2d 642, is a patent-antitrust case in which the United States unsuccessfully tried to persuade the court that a patent and technology licensing agreement between major competitors in the highly concentrated heavy electrical equipment market—Westinghouse, Mitsubishi Electric (Melco) and Mitsubishi Heavy Industries (MHI)—which had the effect of territorially dividing world markets, violated § 1 of the Sherman Act. The Government had two principal theories of the case: (1) the arrangement is in unreasonable restraint of trade because its effect is to lessen competition substantially by precluding the Japanese defendant companies from bidding against Westinghouse on equipment procurements in the United States, when they are ready, willing, and able to do so; and (2) the arrangement is an agreement—explicit or tacit—to divide markets, which is illegal per se under § 1. Neither theory prevailed.
The reverse doctrine of equivalents is a legal doctrine of United States patent law, according to which a device that appears to literally infringe a patent claim, by including elements or limitations that correspond to each element or limitation of the patent claim, nonetheless does not infringe the patent, because the accused device operates on a different principle. That is, "it performs the same or a similar function in a substantially different way." It has been said that "the purpose of the ‘reverse’ doctrine is to prevent unwarranted extension of the claims beyond a fair scope of the patentee’s invention."
