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 Minnesota, tortious interference with contract is recognized as a legal claim when a third party, who is not part of an existing contract, intentionally and improperly interferes with the contract, causing one of the parties to breach it and resulting in damages to the non-breaching party. The non-breaching party can sue the third party for those damages. Minnesota law also extends to claims for interference with prospective contractual relations, protecting not only existing contracts but also business relationships that are expected to culminate in a contract. To establish a claim for tortious interference in Minnesota, the plaintiff must prove the existence of a contract or prospective contractual relationship, the third party's knowledge of the contract or relationship, intentional procurement of the breach, absence of justification, and damages resulting from the interference. However, not all interferences are actionable; Minnesota recognizes that certain competitive behaviors in business may be legitimate and do not constitute tortious interference.