A prescriptive easement—also known as an easement by prescription or an adverse easement—is an easement (right to use property) created by a use of property (the servient estate) that is open, continuous, and adverse to the owner of the property (the servient estate).

To satisfy the requirement that the use be continuous, the use must take place over a required period of time—which may be specified in a state’s court opinions (common law or case law) or in its statutes if the state legislature has written the law regarding easements into statutes or code. If the state legislature has written a law in statutes or codes the law is said to be codified.

In California, a prescriptive easement is acquired when a person uses another's property openly, continuously, and adversely for a period of five years. This is codified in California Civil Code Section 1007 and the Code of Civil Procedure Section 321. The use must be without the owner's permission and in a manner that is visible and obvious. If these conditions are met, the user may be able to claim a legal right to continue using the property despite the owner's objections. It is important to note that the user must pay property taxes on the disputed land to establish a prescriptive easement under California law. Additionally, the California courts require a claimant to prove that they had a good faith belief in their right to use the property, which can be a complex legal issue. Property owners who wish to prevent the establishment of a prescriptive easement on their land should take steps to interrupt the continuous use or provide permission for the use, which can prevent the use from being considered 'adverse.' An attorney can provide specific advice on how to establish or contest a prescriptive easement in California.