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 Iowa, 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 business relationship, the defendant's knowledge of the contract or relationship, intentional and improper interference inducing or causing a breach or termination of the relationship or contract, and resultant damage to the party whose relationship or contract has been disrupted. Iowa law does not require that the interference be done maliciously, but it must be without justification. This means that the interference must be intentional and directed at intentionally causing damage to the contractual relationship or business expectancy. However, not all interferences are actionable. Actions that are considered normal competitive behavior in the marketplace may not constitute tortious interference. The distinction between improper and permissible interference often hinges on the methods used or the intent behind the actions. An attorney can help to determine whether a specific instance of interference may be actionable under Iowa law.