Tortious interference with contract—also known as intentional interference with contractual relations or business expectancy—is a civil claim or cause of action based on interference with a contract or a prospective contract that is about to be completed—by a person or entity who is not a party to the contract (third party).

A claim for tortious interference is based on the idea that the third party encouraged or induced one of the parties to the contract to breach the contract, causing damages to the nonbreaching party, who may sue the third party to recover those damages or losses. In some states there is a requirement that the interference be done maliciously or without justification.

Laws regarding claims for tortious interference with contract vary from state to state. Some states have broadened the protections against interference beyond situations where there is an existing contract and recognize claims for interference with prospective economic advantage or business relations.

But whether there is an existing contract or not, some instances of interference will not create legal liability and will be recognized as legitimate competitive activity, for example.

In Michigan, tortious interference with a contract or business expectancy is recognized as a legitimate legal claim. To establish a case for tortious interference, the plaintiff must prove the existence of a valid contract or a business relationship with the expectancy of future economic benefit, knowledge of the contract or expectancy by the defendant, intentional and improper interference by the defendant inducing or causing a breach or termination of the contractual relationship or expectancy, and resultant damage to the plaintiff. Michigan does not require that the interference be done maliciously, but it must be without justification. This means that the interference must be intentional and not simply incidental to some legitimate purpose. Competitive business activities that are conducted in good faith and do not employ wrongful means typically do not constitute tortious interference. However, actions that are predatory in nature and aim to disrupt contractual relations or business expectancies for the sole purpose of harming the other party may be actionable. It is important for individuals or entities in Michigan to consult with an attorney to understand the nuances of this area of law and to determine whether they have a valid claim or defense related to tortious interference.