Trespassing, the act of entering someone's private property without permission, is illegal. But when a trespasser continues trespassing for an extended period of time, the law may give the trespasser the right to stay on (or pass through) the land under certain circumstances. Typically, however, the trespasser must be living on the land exclusively, openly (without trying to be evasive), and in some case must pay property taxes or even make improvements to the property. This right is known as "adverse possession." These rights range from the right to live on the land, to the right to pass across it to get somewhere else. In some cases, these laws are helpful for homeowners who have inherited property passed down through generations but who lack actual title documentation.

This article provides a general overview of adverse possession and how it works. See FindLaw's guide to state adverse possession laws for more local information.

Requirements for Adverse Possession

If a piece of property has been used by someone other than the rightful owner for a number of years, the doctrine of adverse possession may apply. State laws vary with respect to time requirements; however, typically, the possession by the non-owner needs to be open, notorious, and under a claim of right. In some states, the non-owner must also pay the property taxes on the occupied land. A permissive use of property eliminates the ability to claim adverse possession.

Requirements for a Valid Adverse Possession Claim

A trespasser must meet four elements to legally qualify for a claim to the property, which are:

1. Hostile Claim - The trespasser must either merely occupy the land (with or without knowledge that it is private property); be aware of his or her trespassing; or make an honest mistake (such as relying on an incorrect deed).
2. Actual Possession - The trespasser must be physically present on the land, treating it as their own.
3. "Open and Notorious" Possession - The act of trespassing must be obvious.
4. "Exclusive and Continuous" Possession - Trespasser was in possession of the land for an unbroken period of time, and has not shared possession with others.

Avoiding Adverse Possession: Permission

One common form of trespassing is when a neighbor's driveway or fence encroaches onto someone else's land. Sometimes the owner will not want to make an issue of the encroachment -- either because it seems to be a minor problem or because the neighbor is a friend. To avoid problems later, however, the owner should give the "trespasser" written permission to keep the encroachment for as long as the owner continues to authorize it. If properly handled, this document will prevent the trespasser from acquiring a right to continue the encroachment and from passing along this right to future owners.

Worried About Adverse Possession? Consider Meeting With an Attorney

Hostile claims. Open and notorious possession. Trespassing. This terminology comes from laws written long before your lifetime. And each state has different rules, so it's important to know where you stand. While you may not be familiar with every aspect of real property regulations, you should consider speaking with an experienced real estate lawyer in your area to make sure that your rights are protected.