Vigorous competition is a part of doing business in New York. But, when other parties "cross the line" and engage in unfair and improper conduct, the courts may be able to step in and award damages for the loss of business suffered by victims. One way that this could be done is by a victim filing a lawsuit alleging tortious interference with contract.
Tortious interference can happen whenever there is a valid contract or economic expectancy between a third party and the plaintiff. If the defendant has knowledge of the contract or expectancy and intentionally interferes with it, the plaintiff may be able to recover damages if the interference is improper and the plaintiff suffers damages because of the interference.
In order for a defendant to be liable for the business tort of tortious interference with contract, the interference in question must be improper. There are a number of factors that courts consider when determining whether interference is improper. These include the type of conduct, the actor's interests and motive, the interests of the other parties, the relationship between the parties, the relationship between the actor's behavior and the interference, the social interests in protecting the contract versus protecting the actor's freedom of action and the damages suffered.
Whether interference is improper or not depends on the facts of the case. For example, if a business person refuses to do business with another because they find a business partner of theirs to be morally distasteful, it probably will not be considered to be an improper motive. But, if the business person wishes to put another company out of business, or if they wish to take away the advantages of their business relationship, then an improper motive may be found that will prompt damages for tortious interference.
Source: FindLaw, "Tortious Interference," accessed on Sept. 1, 2017