Tortious interference is a legal theory intended to allow parties to contract to fulfill contractual obligations without thirdparty interference. If a third party unfairly interferes with a business contract or relationship and causes damage, a tortious interference claim may be a viable option.Tortious interference with business relations involves a third party using false claims against a business in order to drive business away. Tortious interference with a contract occurs when a third party intentionally damages the contractual between two parties. Texas Tortious Interference with Contract Law: Tortious Interference vs. For example, interference is only wrongful if it is intentional. Legal Standard for Tortious Interference with Contract. Under Texas law, a party claiming tortious interference with contract must show. Tortious interference with existing contracts and prospective business relationships, and civil conspiracy. For example, interference is only wrongful if it is intentional.