Me. Rev. Stat. tit. 24-A, § 2680

Administrators providing payment or reimbursement for diagnosis or treatment of a condition or a complaint by a licensed health care practitioner or licensed hospital shall accept the current standardized claim form for professional or facility services, as applicable, approved by the Federal Government and submitted electronically, and any claims for facility services must identify the physical location, including hospital off-campus locations, where services are provided. An administrator may not be required to accept a claim submitted on a form other than the applicable form specified in this section and may not be required to accept a claim that is not submitted electronically, except from a health care practitioner who is exempt pursuant to Title 24, section 2985.