Usucaption (in U.S. and U.K. known as acquisitive prescription), is a concept found in civil law

Civil law (legal system)

Civil law is a legal system inspired by Roman law and whose primary feature is that laws are codified into collections, as compared to common law systems that gives great precedential weight to common law on the principle that it is unfair to treat similar facts differently on different...

 systems and has its origin in the Roman law

Roman law

Roman law is the legal system of ancient Rome, and the legal developments which occurred before the 7th century AD — when the Roman–Byzantine state adopted Greek as the language of government. The development of Roman law comprises more than a thousand years of jurisprudence — from the Twelve...

 of property

Property law

Property law is the area of law that governs the various forms of ownership in real property and in personal property, within the common law legal system. In the civil law system, there is a division between movable and immovable property...

.

Usucaption is a method by which ownership

Ownership

Ownership is the state or fact of exclusive rights and control over property, which may be an object, land/real estate or intellectual property. Ownership involves multiple rights, collectively referred to as title, which may be separated and held by different parties. The concept of ownership has...

 of property can be gained by lapse of time (acquiescence

Acquiescence

Acquiescence is a legal term used to describe an act where a person knowingly stands by without raising any objection to the infringement of their rights, while someone else unknowingly and without malice aforethought makes a claim on their rights...

). While usucaption has been compared with adverse possession

Adverse possession

Adverse possession is a process by which premises can change ownership. It is a common law concept concerning the title to real property . By adverse possession, title to another's real property can be acquired without compensation, by holding the property in a manner that conflicts with the true...

 (that is, squatting

Squatting

Squatting consists of occupying an abandoned or unoccupied space or building, usually residential, that the squatter does not own, rent or otherwise have permission to use....

), the true effect of usucaption is to remedy defects in title.

The necessity for usucaption arose in Roman law with the divide between res mancipi and res nec mancipi. Res mancipi required elaborate and inconvenient methods to transfer title

Title (property)

Title is a legal term for a bundle of rights in a piece of property in which a party may own either a legal interest or an equitable interest. The rights in the bundle may be separated and held by different parties. It may also refer to a formal document that serves as evidence of ownership...

 (a formal mancipatio ceremony, or in iure cessio). Res nec manicipi could be transferred by traditio (delivery) or in iure cessio.

If res mancipi were transferred by traditio, full ownership would not pass and the recipient would become a bonitary owner. However, if the bonitary owner kept the res in his possession for a certain amount of time (two years for land, one year for chattels) his title would become full title and he could assert himself as dominus

Dominus (title)

Dominus is the Latin word for master or owner. As a title of sovereignty the term under the Roman Republic had all the associations of the Greek Tyrannos; refused during the early principate, it finally became an official title of the Roman Emperors under Diocletian...

.