What Is Adverse Possession in California?

Adverse possession is the doctrine that lets a person acquire actual ownership of land they do not hold title to by possessing it long enough under the conditions the law requires. It is rare, and it is intentionally hard to prove.

In California the claimant must show possession that is actual, open and notorious, hostile to the true owner's title, exclusive, and continuous for five years, and must also have paid all property taxes assessed on the land during that period. The tax requirement defeats most claims: neighbors who fence in a strip of land almost never pay taxes on it separately. Claims that fail as adverse possession sometimes succeed as prescriptive easements instead, which follow similar elements but confer only a right of use and drop the tax requirement.

These disputes typically surface during a sale, a survey, or a fence replacement, when a boundary everyone assumed for decades turns out to be in the wrong place. Related doctrines such as agreed boundary and good faith improver claims often travel with them.