Title to ‘your’ property might be claimed by another under the theory of adverse possession. Such arises from possession of the property by another for a period of 5 years, while occupying same in an open and notorious, hostile and adverse manner, under color of title or claim of right and paying tax on that property during that time period. It is possible to acquire a prescriptive easement as an alternative, based on the same requirements except for the payment of property tax which is not necessary.
Other examples of claims against title are those arising from an option to purchase, an implied easement, a specific performance action on a purchase contract, a constructive or purchase money trust, and a lien or conveyance of , or not of , record.
Certain claims affecting your title are covered under a title insurance policy. It is very important when purchasing property to obtain a policy with the maximum coverage; counsel can make that determination especially with regards the particular transaction.