Second, the defendant must have acted in pursuit of some purpose considered improper. Intent to interfere can be demonstrated by evidence of the defendant's knowledge of a contractual relationship between two parties and conduct such that defendant knows that interference will result. Improper purpose is determined by the circumstances of each particular case. In light of these factors, courts have imposed liability on a broad spectrum of conduct found to be improper. A refusal to deal has been held to be improper where it was coupled with a threat or demand that a contract be breached.
Many states have the tort of intentional interference with contractual relations.
An easy way to start your business buying power is with the clout of an American Express small business card. When new vendors are reluctant to give you as a new business owner 'net 30' terms, this is an alternative or may sway your vendor's choice.