A quasi-contract is a fictional contract recognised by a court. The notion of a quasi-contract can be traced to Roman law and is still a concept used in some modern legal systems. Quasi Contract laws have been deduced from the Latin statement "Nemo debet locupletari ex aliena jactura", which proclaims that no man should grow rich out of another person's loss. It was one of the central doctrines of Roman law.
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".
The forms of action were the different procedures by which a legal claim could be made during much of the history of the English common law. Depending on the court, a plaintiff would purchase a writ in Chancery which would set in motion a series of events eventually leading to a trial in one of the medieval common law courts. Each writ entailed a different set of procedures and remedies which together amounted to the "form of action".
In laws of equity, unjust enrichment occurs when one person is enriched at the expense of another in circumstances that the law sees as unjust. Where an individual is unjustly enriched, the law imposes an obligation upon the recipient to make restitution, subject to defences such as change of position. Liability for an unjust enrichment arises irrespective of wrongdoing on the part of the recipient. The concept of unjust enrichment can be traced to Roman law and the maxim that "no one should be benefited at another's expense": nemo locupletari potest aliena iactura or nemo locupletari debet cum aliena iactura.
The law of restitution is the law of gains-based recovery, in which a court orders the defendant to give up their gains to the claimant. It should be contrasted with the law of compensation, the law of loss-based recovery, in which a court orders the defendant to pay the claimant for their loss.
Assumpsit, or more fully, action in assumpsit, was a form of action at common law used to enforce what are now called obligations arising in tort and contract; and in some common law jurisdictions, unjust enrichment. The origins of the action can be traced to the 14th century, when litigants seeking justice in the royal courts turned from the writs of covenant and debt to the trespass on the case.
The law of contract in Australia is similar to other Anglo-American common law jurisdictions.
Fibrosa Spolka Akcyjna v Fairbairn Lawson Combe Barbour Ltd[1942] UKHL 4 is a leading House of Lords decision on the doctrine of frustration in English contract law.
English contract law is the body of law that regulates legally binding agreements in England and Wales. With its roots in the lex mercatoria and the activism of the judiciary during the industrial revolution, it shares a heritage with countries across the Commonwealth, from membership in the European Union, continuing membership in Unidroit, and to a lesser extent the United States. Any agreement that is enforceable in court is a contract. A contract is a voluntary obligation, contrasting to the duty to not violate others rights in tort or unjust enrichment. English law places a high value on ensuring people have truly consented to the deals that bind them in court, so long as they comply with statutory and human rights.
The English law of unjust enrichment is part of the English law of obligations, along with the law of contract, tort, and trusts. The law of unjust enrichment deals with circumstances in which one person is required to make restitution of a benefit acquired at the expense of another in circumstances which are unjust.
Change of position is a defence to a claim in unjust enrichment which operates to reduce a defendant's liability to the extent to which his or her circumstances have changed as a consequence of an enrichment.
Quasi-tort is a legal term that is sometimes used to describe unusual tort actions, on the basis of a legal doctrine that some legal duty exists which cannot be classified strictly as negligence in a personal duty resulting in a tort nor as a contractual duty resulting in a breach of contract, but rather some other kind of duty recognizable by the law. It has been used, for example, to describe a tort for strict liability arising out of product liability, although this is typically simply called a 'tort'.
Contract law regulates the obligations established by agreement, whether express or implied, between private parties in the United States. The law of contracts varies from state to state; there is nationwide federal contract law in certain areas, such as contracts entered into pursuant to Federal Reclamation Law.
Baltic Shipping Company v Dillon, the Mikhail Lermontov case, is a leading Australian contract law case, on the incorporation of exclusion clauses and damages for breach of contract or restitution for unjust enrichment.
The English law of Restitution is the law of gain-based recovery. Its precise scope and underlying principles remain a matter of significant academic and judicial controversy. Broadly speaking, the law of restitution concerns actions in which one person claims an entitlement in respect of a gain acquired by another, rather than compensation for a loss.
Lampleigh v Brathwait [1615] EWHC KB J 17, (1615) Hobart 105, 80 ER 255 is a case on implied assumpsit and past consideration in English contract law.
Sumpter v Hedges [1898] 1 QB 673 is an English contract law case, concerning substantial performance of a contract and restitution for unjust enrichment.
Cobbe v Yeoman's Row Management Ltd[2008] UKHL 55 is a House of Lords case in English land law and relates to proprietary estoppel in the multi-property developer context. The court of final appeal awarded the project manager £150,000 on a quantum meruit basis for unjust enrichment because Yeoman's Row had received the benefit of his services without paying for that. The court refused to find or acknowledge a binding contract, prior arrangement with a third party or promise, overturning a £2m award on the basis of a possible lien arising from a promise over the property. The court found a non-binding agreement in principle, entirely subject to the owner's final say to take into account for example their view of the market; this was the basis on the facts on which the parties were proceeding.
Davis Contractors Ltd v Fareham Urban District Council [1956] UKHL 3 is an English contract law case, concerning the frustration of an agreement.
BP Exploration Co (Libya) v Hunt [1983] 2 AC 352 is an English contract and unjust enrichment case, concerning the frustration of an agreement.
