Every health care service contractor shall file with its annual statement with the insurance commissioner a master list of the participating providers with whom or with which such health care service contractor has executed contracts of participation, certifying that each such participating provider has executed such contract of participation. The health care service contractor shall on the first day of each month notify the insurance commissioner in writing in case of the termination of any such contract, and of any participating provider who has entered into a participating contract during the preceding month.
RCW 48.44.080