Mass. Gen. Laws ch. 32A, § 11A
(c) The name, address, and certificate number of a person eligible for health insurance or coverage pursuant to paragraph (a) or (b), if available, shall be forwarded by the plan or contractor, whichever is applicable, to the department of public welfare within thirty days of the date when coverage of said person under said paragraph (a) or (b) is commenced.
Notice of cancellation of coverage of the divorced or separated spouse of a member shall be mailed to such divorced or separated spouse at such person's last known address, together with notice of the right to reinstate coverage retroactively to the date of cancellation.
Claims paid on behalf of a divorced or separated spouse or on behalf of a dependent who is not residing with the member shall be paid to the physician, hospital or other provider of covered services or to the person on whose behalf such services were performed, unless the person is a minor child. In the event the person on whose behalf such services were performed is a minor, payment shall be made to the physician, hospital or other provider of such services or to the parent or custodian with whom the child resides.