New Yorkers need New York No Trespassing signs! The signs are printed with state trespassing code N.Y. U.C.C . § 140.05 for residents to warn trespassers they're breaking the law. New York defines trespassing as when a person "knowingly enters or remains unlawfully in a building or upon real property." Messages are printed with 3M ink that lasts for years on durable aluminum that won't rust or fade. For urbanites, check out our special NYC No Trespassing Sign that states that loiterers and trespassers will be arrested by the NYC police department.