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

A subscription certificate shall be issued to each subscriber of an optometric service corporation. Any agreement between an optometric service corporation and a group of ten or more persons or with the employer, employers or other representatives of such group whereby the optometric service corporation undertakes to furnish benefits for optometric service to said persons and their covered dependents, if any, shall be considered a group optometric service agreement. Under a group or non-group optometric service agreement, the form of the subscription certificate, the extent of optometric services contained therein, and the premiums charged by such corporation to the subscriber shall be filed with and receive the prior approval of the commissioner. No such agreement shall be approved if he finds that the extent of optometric services offered therein are unreasonable in relation to (a) the premium charged for such services, and (b) to the economic practicality of providing for such prepaid services, or if the premium charges are excessive, inadequate or unfairly discriminatory. No subscription certificate shall be issued unless the commissioner shall have approved in writing the form of certificate nor unless it contains in substance the following provisions:--