Ind. Code § 27-13-17-1

Sec. 1. An agreement between a provider and a health maintenance organization under which the provider agrees to provide health care services must require the provider to give the organization at least sixty (60) days advance notice before terminating the agreement unless the provider or the group of providers provide thirty percent (30%) or more of the health maintenance organization services, in which case the provider must give at least one hundred twenty (120) days advance notice.