In New York, to prevail on a claim of adverse possession, a plaintiff must establish that his possession of the disputed property was hostile and under a claim of right, actual, open, notorious, exclusive and continuous for 10 years. These elements must be established by clear and convincing evidence. All that is required is a showing that the possession constitutes an actual invasion of or infringement upon the owner’s rights. For example, a person who fences off a portion of an owner’s property for ten years, and claims it as his own, will acquire the property by adverse possession after ten years unless the owner takes action to disclaim the actions of the other person.
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