Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 176G, § 6

A health maintenance organization may enter into contractual arrangements with any other person or company for the provision, to the health maintenance organization, of health services, insurance, reinsurance and administrative, marketing, underwriting or other services on a nondiscriminatory basis. A health maintenance organization shall not refuse to contract with or compensate for covered services an otherwise eligible provider solely because such provider has in good faith communicated with one or more of his current, former or prospective patients regarding the provisions, terms or requirements of the organization's products as they relate to the needs of such provider's patients.

No contract between a participating provider of health care services and a health maintenance organization shall be issued or delivered in the commonwealth unless it contains a provision requiring that within 45 days after the receipt by the organization of completed forms for reimbursement to the provider of health care services, the health maintenance organization shall (i) make payments for such services provided, (ii) notify the provider in writing of the reason or reasons for nonpayment, or (iii) notify the provider in writing of what additional information or documentation is necessary to complete said forms for such reimbursement. If the health maintenance organization fails to comply with this paragraph for any claims related to the provision of health care services, said health maintenance organization shall pay, in addition to any reimbursement for health care services provided, interest on such benefits, which shall accrue beginning 45 days after the health maintenance organization's receipt of request for reimbursement at the rate of 1.5 per cent per month, not to exceed 18 per cent per year. The provisions of this paragraph relating to interest payments shall not apply to a claim that the health maintenance organization is investigating because of suspected fraud. No contract between a participating home health agency or a participating licensed hospice agency and a health maintenance organization shall be issued or delivered in the commonwealth that requires the participating home health agency or participating licensed hospice agency to be accredited by the Joint Commission on Accreditation of Healthcare Organizations or other national accrediting body if it is certified for participation in the Medicare program, Title XVIII of the federal Social Security Act, 42 U.S.C. Sections 1395 et seq.