In common law-jurisdictions, quasi-contract law can be attributed to the medieval form of action known as indebitatus assumpsit. In essence, the applicant would claim a sum of money from the defendant, as if the defendant had promised to pay it, that is, as if there were a contract between the parties. The defendants` promise – their consent to be bound by the “contract” – was implied by law. Quasi-contract law has generally been used to enforce restitution obligations.  Quasi-contracts describe one party`s obligation to another party if the party is in possession of the original party`s assets. These parties do not necessarily have to have entered into a prior agreement. The agreement is legally imposed by a judge as an appeal if person A owes something to person B, because he indirectly or accidentally comes into possession of person A`s property. The contract becomes enforceable if person B decides to keep the object in question without paying. However, the government may take action against an accused to recover funds paid illegally or improperly, including those paid on the basis of a misunderstanding of the facts, in a quasi-contractual legal action for unjustified enrichment. See z.B. Mt. Sinai Hospital of Greater Miami v.
Weinberger, 517 F.2d 329 (5 cir. 1975); J.W. Bateson Co., Inc. vs. United States, 308 F.2d 510, 514-515 (5th Cir. 1962); Kingman Water Co. v. United States, 253 F.2d 588 (9th Cir. 1958); United States v. Independent School District No. 1 of Okmulgee, OK, 209 F.2d 578 (10th Cir.
1954); United States v. Bentley, 107 F.2d 382 (2d Cir. 1939). Similarly, the United States may recover the value of the services provided by the State in the event of an error in the merits of the recipient. United States v. Shanks, 384 F.2d 721 (10 cir. 1967). Since the agreement is established in court, it is legally enforceable, so neither party is obliged to approve it. The purpose of quasi-treaty is to achieve a fair result in a situation where one party has an advantage over another. The defendant – the party who acquired the property – must reimburse the claimant, who is the injured party, to cover the value of the object. . .