Tortious interference, sometimes also known as intentional interference with contractual or business relations, is a common law tort claim. Pennsylvania Supreme Court Opens Door for Terminated AtWill Employees to File Tortious Interference Claims Against Third Parties.A Standard Clause providing model language that a plaintiff can use to plead a claim for tortious interference with contract under Pennsylvania law. Tortious interference happens when your competitor tries to break or damage an economic agreement or contract your business has with a third party. Super. Ct. 1991) ("The tort of interference with contract is defined in terms of unprivileged interference with a contract with a third party. In a contract case, this means showing both interference and a wrongful act. 2d 10, 19 (Pa. Super. 2002). On February 21, 2024, in the case of Salsberg v. Tortious interference was first recognized in Florida in 1966 in the case of Allen v. Leybourne, 190 So.2d 825 (Fla.