Squatter's rights confer ownership of real estate on a person who occupies someone else's property for a set amount of time, under certain conditions. The underlying legal principle is adverse possession, an idea that dates back hundreds of years to British Common Law, notes Mental Floss.
In 1979, the California Court of Appeals for the Third District upheld the idea of adverse possession because the historical preference for property is that someone uses it rather than having it simply sit unused, reports Mental Floss. One example of adverse possession would involve a person moving into an unoccupied house and establishing utility accounts. The owner of the house may have moved away and left it vacant for any number of reasons, ranging from a pending foreclosure to a messy divorce. The person who moves in may claim adverse possession, having accumulated squatter's rights during the time of period set by law, according to Mental Floss.
The amount of time that a squatter must live in the property without any objection from the owner before claiming title to it varies widely. In California, it only takes five years, but in New Jersey, the squatter has to live in the property for 30 years without the titled owner mounting any sort of objection in order to claim title, states Mental Floss.