The Basics of the Doctrine of Adverse Possession

As an attorney who practices extensively in the area of real property litigation, I am frequently called upon to prosecute or defend cases involving a claim of adverse possession, and   am   approached by individuals who either have only a basic understanding of what adverse possession is, or who have formed misconceptions about what it means and how the doctrine is applied.     This article is intended as a primer for non-attorneys — individuals who are interested in learning the basic contours of the doctrine of adverse possession as it applies in the state of Washington (although the law of adverse possession is similar if not identical in most states).



What is Adverse Possession?


In its most basic sense, “adverse possession” is a legal doctrine that allows a person to acquire legal ownership of property that he treats as his own, if he does so for a long enough period of time, even though the property is not his own.   In other words, a person who uses another person’s property, without permission, for a long enough period of time, can acquire legal ownership of that property.   As an   example,   if   a fence   separates two properties — Parcel A and Parcel B — but   does not run along the actual property line,   a portion of Parcel B might be   located on Parcel A’s side of the fence.


If the owner of Parcel A mows and tends to all areas of his property right up to the fence (and is therefore maintaining parts of Parcel B), and does so for the requisite length of time, the owner of Parcel A might be able to acquire legal title to that portion of Parcel B that he has maintained.


Most people are familiar with statutes of limitation.   A statute of limitation sets forth a time period within which one must sue to enforce a right, failing which the person loses the right to sue.   The statute of limitation for a trespass action in Washington is ten (10) years.         If an owner allows another person to continue trespassing on his property and does nothing about it for ten years, the trespasser can acquire legal title to the complacent owner’s land.   Thus, adverse possession is nothing more than a statute of limitation for bringing a trespass action.   After ten years of trespassing, the trespasser can go to court to seek a declaration that the owner has allowed the statute of limitation to pass, and that the claimant     has therefore acquired title to that property.


The Elements of Adverse Possession


A person claiming title to land by adverse possession (I shall refer to such a person as the “claimant”) must prove four basic elements.   The claimant must show that she or he used property belonging to another in a way that was (1) open and notorious, (2) actual and uninterrupted, (3) exclusive, and (4) hostile.[1]


Possession (i.e. use)  of the property that includes  each of the necessary elements must exist for ten years,[2] following which the claimant can go to court and acquire legal title to the property.   As stated above, adverse possession is merely a statute of limitation for trespass.   Thus,   if the title owner of land has knowledge that another person is using his land openly and without his permission, he can sue that person for trespass.   However, if the title owner allows the trespass to continue for ten years, he loses his right   to sue the claimant.   Each of the four elements stated above exists to protect the diligent owner, and also to reward those who productively use land.


Sneaking onto another’s property in the dead of night and ‘using the property’ until the break of dawn is not “open and notorious,” because the true owner would not reasonably be aware of the clandestine use of his property.   For this reason, such surreptitious use of another’s land will never ripen into an adverse possession claim no matter how long it goes on.


Likewise, using another’s property openly and exclusively for one year, but then vacating for some period of time, then occupying it for another year, then vacating (and so on) is not “actual and uninterrupted.”   Thus, even if such intermittent use continues over the course of fifty years such that cumulatively the land has been used and occupied for ten years, such use would not give rise to an adverse possession claim, since the claimant would be unable to establish   an uninterrupted use.


The requirement that the claimant use the land “exclusively” protects a title owner of land who decides to let everyone use his property.


Finally, the “hostile” element does not have the normal definition of ‘hostile;’ it does not mean enmity or ill will.   Rather, ‘hostile’ in the adverse possession context merely means ‘without the owner’s permission.’   Thus, a landowner can explicitly give his permission to allow another to use his land for 100 years and not be subject to a claim of adverse possession.   Think of a landlord who rents to a tenant for more than ten years:   the tenant is there pursuant to an agreement with the owner, and does not adversely possess the property.



Common Defenses


Like all legal doctrines, there are exceptions to the general rules regarding adverse possession, as well as several defenses.   For example, public land can never be adversely possessed.   Open, continuous, exclusive and non-permissive use of land, where the land is owned by the city, county or state, cannot form the basis of an adverse possession claim.


Most “defenses” to an adverse possession claim involve simply proving the non-existence of one or more of the required elements.   The word ‘defense’ in the preceding sentence is put in quotation marks because asserting that   a statute of limitation bars the action, or that another element necessary to an adverse possession claim is absent,   is itself generally considered a defense. Since adverse possession is itself essentially the assertion of a statute of limitation defense to a trespass action, labeling efforts to resist such an assertion a “defense” seemingly puts the terms “claim” and “defense” on their heads.


“Neighborly accommodation” is one of the most common defenses to an adverse possession claim when dealing with developed residential property.   Suppose two houses share a common boundary comprised of a lawn, with no fence separating the two properties.   Allowing your neighbor to walk on, use, or maintain portions of your property may merely be a neighborly accommodation on your part.   Obviously, it would make bad public policy to require neighbors to constantly insist upon asserting their property rights vis-à-vis their neighbor, and accordingly the “neighborly accommodation” defense arose to lessen the tension between encouraging the productive use of land, on the one hand, and avoiding neighbor-on-neighbor acrimony, on the other.


For example, suppose “Bill” and “John” own the neighboring properties described above (sharing a common boundary comprised of a lawn, with no fence separating the two parcels).   Suppose Bill routinely mows the front lawn, including portions of the lawn on John’s side of the property line.   Suppose also that throughout the year, Bill sits on lawn chairs placed in the vicinity of the boundary line, occasionally setting up his chair on John’s side of the line, and occasionally on his own side of the line.   The neighborly accommodation defense would protect John from losing part of his property were Bill to bring a claim for adverse possession.   Bill might be able to prove that he openly, continuously, and exclusively used portions of John’s property and never once sought or received permission from John.   John, however, could defend against such a claim by demonstrating that he was merely extending a neighborly accommodation by not protesting Bill’s use of the property or suing Bill for trespass.   The ‘neighborly accommodation’ defense has its limits, such as where Bill unilaterally decides to build a fence between the two properties, does not consult with John prior to erecting the fence, and it is later determined that the fence encroaches upon John’s property.    Generally, however, courts have stuck to the rule that true owners often do (and should) permit third persons to use their property on an occasional, transitory manner, and that not all use is adverse in this sense.


Some defenses, while common, apply only to certain types of land.   The so-called “vacant land doctrine” applies (as its name suggests) to open, vacant, undeveloped land.   The vacant land doctrine applies a presumption that the use of vacant, undeveloped land is done with the permission of the owner.   If that presumption applies, the claimant must then put forth evidence to rebut that presumption.   In such cases, use which might have been sufficient to establish adverse possession if done on developed property is insufficient when done on vacant land.


One of the most common circumstances giving rise to adverse possession claims occurs when the owner (who I shall call “Owner A”) of property obtains a survey (usually for some reason other than in connection with a boundary dispute), and the survey reveals a disparity between the legal/surveyed property line and a boundary fence.   Owner A realizes that the fence separating his property from his neighbor’s property — a fence that was present when Owner A bought the property and which Owner A always assumed marked the true legal boundary — is five feet closer to Owner A’s house than the true property line.   Owner A understandably asks: “Can I move the fence so that it coincides with the surveyed/legal property line, since that will give me five more feet of yard running the entire length of the fence?”   Unfortunately, the answer to that question is “It depends.”


Adverse possession cases often proceed to trial (rather than being resolved based on a summary judgment motion or other pre-trial disposition) precisely because the questions are so fact-specific.   Often, one or both of the parties has not personally owned the property   for the entire ten year period, in which case it is necessary to investigate how the prior owner(s) used the property, and whether there were any explicit agreements between the prior owners (generally, the prior owner’s use “counts” toward the current owner’s claim).




Adverse Possession is, quite literally, a doctrine that legalizes the theft of land under certain circumstances.   It is a very unintuitive rule in this sense.


However, the elements of adverse possession, as well as the most common defenses to it, along with the extraordinarily long period of time required to establish the claim, together operate to deprive an owner of his property only when the owner unreasonably sits on his rights for an extended period of time.


Hopefully the foregoing article explains the basics of this doctrine.

[1] Chaplin v. Sanders,  100 Wn.2d 853, 857, 676 P.2d 431 (1984).


[2] RCW 4.16.020.