Legal Question in Real Estate Law in New York

If you were also using it with his knowledge you may have a claim of adverse possession. You would need to pursue this in court.

Did you have his permission to enter the property?

On the other hand, maybe there is an error on your survey that makes you think that you actually owned that lot.

Adverse possession is very complicated and very hard. If you want to push the claim, your most likely avenue is to be a gadfly whom the seller will pay to go away.

You will definitely need a lawyer to handle this.

you might have a cause of action under the law of adverse possession. You need to hire a lawyer to file a declaratory action

To make out a claim of adverse possession, you have to have possessed the property adversely (not with the owner's consent) openly and notoriously for more than ten years under a claim of right.

Who's been paying taxes on the property?

Now you may have a defense to a trespass action by the record owner, because unless an owner can show that he or his predecessor in title had possession of the premises within ten years before the action was filed, he will not prevail. But just because the statute of limitations to throw you off the land has expired does not give the kind of title that you could mortgage or sell. For that, you need adverse possession, which requires a claim of right.