Usucapio was a concept in Roman law that dealt with the acquisition of ownership of something through possession. It was subsequently developed as a principle of civil law systems, usucaption. It is similar to the common law concept of adverse possession, or acquiring land prescriptively. Overview Since mancipatio and in iure cessio were inherently public modes of acquisition of ownership, usucapio was the only private method of the ius civile. Ownership of a thing in Roman law was usually protected forever, until a limit of thirty years was introduced in 426 AD on actions by Theodosius – in other words, preventing the owner of a thing getting it back or seeking damages after thirty years. Usacapio was a form of acquisitive prescription – the passage of time entitled the holder to particular rights of acquisition. This right is a new right, one without reference to any existing rights. Usucapio assisted two cases: where a thing had been transferred improperly (for example, transferring a res mancipi by traditio), or where the transferor of a thing did not hold proper title (for example, sale by a non-owner). Requirements There were five requirements for the acquisition of ownership by usucapio. Firstly, the claimant must have had uninterrupted possession for the required period of time. The claimant must have gained the thing with iusta causa and in good faith (bona fides). The thing claimed must be capable of ownership, and must have at no time been stolen or taken by force. Possession The required period of time was only one year for movables and two years for land. Res universitas, groups of things such as an inheritance which may include both movables and land, also came under the one year rule. This is widely attributed to the time of the Twelve Tables, including by Cicero. The requirement of extended possession is believed to have been originally the only requirement, although certain types of things were exempt. These included stolen things, the res mancipi under another's guardianship, and limes – five-foot strips required between adjoining land holdings. The time period would have formed the prohibitive part in early Rome, where the community was sufficiently small that the owner could easily identify and regain his goods – considering also that if they had been stolen, they could not be usucapted. Usucapio would therefore have been restricted in most cases to informal conveyance of res mancipi. As