In common-law legal systems, laches is a lack of diligence and activity in making a legal claim, or moving forward with legal enforcement of a right, particularly in regard to equity. This means that it is an unreasonable delay that can be viewed as prejudicing the opposing party. When asserted in litigation, it is an equity defense, that is, a defense to a claim for an equitable remedy. It is often understood in comparison to a statute of limitations, a statutory defense, which traditionally is a defense to a claim "at law".
Maxims of equity are legal maxims that serve as a set of general principles or rules which are said to govern the way in which equity operates. They tend to illustrate the qualities of equity, in contrast to the common law, as a more flexible, responsive approach to the needs of the individual, inclined to take into account the parties' conduct and worthiness. They were developed by the English Court of Chancery and other courts that administer equity jurisdiction, including the law of trusts. Although the most fundamental and time honored of the maxims, listed on this page, are often referred to on their own as the 'maxims of equity' or 'the equitable maxims', it cannot be said that there is a definitive list of them. Like other kinds of legal maxims or principles, they were originally, and sometimes still are, expressed in Latin.
An affirmative defense to a civil lawsuit or criminal charge is a fact or set of facts other than those alleged by the plaintiff or prosecutor which, if proven by the defendant, defeats or mitigates the legal consequences of the defendant's otherwise unlawful conduct. In civil lawsuits, affirmative defenses include the statute of limitations, the statute of frauds, waiver, and other affirmative defenses such as, in the United States, those listed in Rule 8 (c) of the Federal Rules of Civil Procedure. In criminal prosecutions, examples of affirmative defenses are self defense, insanity, entrapment and the statute of limitations.
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 their word; the person so prevented is said to be "estopped". Estoppel may prevent someone from bringing a particular claim. Legal doctrines of estoppel are based in both common law and equity. Estoppel is also a concept in international law.
Adverse possession, sometimes colloquially described as "squatter's rights", is a legal principle in common law under which a person who does not have legal title to a piece of property—usually land —may acquire legal ownership based on continuous possession or occupation of the property without the permission (licence) of its legal owner.
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.
Quantum meruit is a Latin phrase meaning "what one has earned". In the context of contract law, it means something along the lines of "reasonable value of services".
Central London Property Trust Ltd v High Trees House Ltd [1947] KB 130 is a famous English contract law decision in the High Court. It reaffirmed and extended the doctrine of promissory estoppel in contract law in England and Wales. However, the most significant part of the judgment is obiter dicta as it relates to hypothetical facts; that is, the landlord did not seek repayment of the full wartime rent.
The Nonintercourse Act is the collective name given to six statutes passed by the United States Congress in 1790, 1793, 1796, 1799, 1802, and 1834 to set boundaries of American Indian reservations. The various acts were also intended to regulate commerce between White Americans and citizens of Indigenous nations. The most notable provisions of the act regulate the inalienability of aboriginal title in the United States, a continuing source of litigation for almost 200 years. The prohibition on purchases of Indian lands without the approval of the federal government has its origins in the Royal Proclamation of 1763 and the Confederation Congress Proclamation of 1783.
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.
Estoppel in English law is a doctrine that may be used in certain situations to prevent a person from relying upon certain rights, or upon a set of facts which is different from an earlier set of facts.
An equitable servitude is a term used in the law of real property to describe a nonpossessory interest in land that operates much like a covenant running with the land. In England and Wales the term is defunct and in Scotland it has very long been a sub-type of the Scottish legal version of servitudes, which are what English law calls easements. However covenants and equitable servitudes in most of the jurisdictions across North America, are slightly different. The usual distinction is based on the remedy plaintiff seeks and precedent will allow for the scenario in question. Where the terms are unmerged, holders of a covenant seek money damages; holders of equitable servitudes seek injunctions. The term used to exist in England widely before Tulk v Moxhay and as byproduct of the Judicature Acts became one of the fullest mergers of equity and common law in England and Wales so as to agree initially on the term "equitable covenant", then coming to be united in the term covenant save that "equitable" bears a particular meaning in English property rights since at least 1925: it means not fully compliant with registration/written formalities. If lacks legally routine formalities it is not a full legal covenant and therefore more tenuous, often only enforceable personally and against the original covenantor.
Steinberg v. Columbia Pictures Industries, Inc., 663 F. Supp. 706 was a federal case in which artist Saul Steinberg sued various parties involved with producing and promoting the 1984 movie Moscow on the Hudson, claiming that a promotional poster for the movie infringed his copyright in a magazine cover, View of the World from 9th Avenue, he had created for The New Yorker.
A trademark is a type of intellectual property consisting of a recognizable sign, design, or expression that identifies a product or service from a particular source and distinguishes it from others. A trademark owner can be an individual, business organization, or any legal entity. A trademark may be located on a package, a label, a voucher, or on the product itself. Trademarks used to identify services are sometimes called service marks.
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.
Proprietary estoppel is a legal claim, especially connected to English land law, which may arise in relation to rights to use the property of the owner, and may even be effective in connection with disputed transfers of ownership. Proprietary estoppel transfers rights if
City of Sherrill v. Oneida Indian Nation of New York, 544 U.S. 197 (2005), was a Supreme Court of the United States case in which the Court held that repurchase of traditional tribal lands 200 years later did not restore tribal sovereignty to that land. Justice Ruth Bader Ginsburg wrote the majority opinion.
The United States was the first jurisdiction to acknowledge the common law doctrine of aboriginal title. Native American tribes and nations establish aboriginal title by actual, continuous, and exclusive use and occupancy for a "long time." Individuals may also establish aboriginal title, if their ancestors held title as individuals. Unlike other jurisdictions, the content of aboriginal title is not limited to historical or traditional land uses. Aboriginal title may not be alienated, except to the federal government or with the approval of Congress. Aboriginal title is distinct from the lands Native Americans own in fee simple and occupy under federal trust.
Taylor Fashions Ltd and Old & Campbell Ltd v Liverpool Victoria Trustees Co Ltd [1979] is a leading case in English land law on proprietary estoppel. Due to a common mistake and no element of enticement to believe that mistake, estoppel was not available on the facts.
Petrella v. Metro-Goldwyn-Mayer, Inc., 572 U.S. 663 (2014), is a United States Supreme Court copyright decision in which the Court held 6-3 that the equitable defense of laches is not available to copyright defendants in claims for damages.
