Under New York law, a tort action for interference with a contractual relationship must be based upon five essential elements. "A cause of action for tortious interference with contract generally accrues when an injury is sustained" (American Federal Group, Ltd.If a third party unfairly interferes with a business contract or relationship and causes damage, a tortious interference claim may be a viable option. Cheryl Keeling sued the property manager of her condominium and a real estate broker for defamation and tortious interference with economic advantage. As implied, this type of interference requires a formal business agreement or contract already be in place and then be interfered with. Tortious Interference with Prospective Business Relations. Private nuisances are not accomplished solely due to entries onto the land others.