Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 23N, § 10

(a) An operator shall adopt comprehensive house rules for game play governing sports wagering transactions with the operator's patrons. The house rules shall specify the amounts to be paid on winning wagers and the effect of sports event schedule changes. An operator shall not conduct sports wagering until the commission has approved the house rules and an operator shall not conduct sports wagering in a manner inconsistent with approved house rules.

(b) The house rules, together with any other information the commission deems appropriate, shall be accessible to any patrons of the sports wagering operator. The operator shall make copies readily available to patrons and shall post the house rules as required by the commission, including on a prominent place on the operator's public website and mobile application or other digital platform.