(1) An employer (other than a self-insurer) who is a respondent to an application for arbitration must serve a copy of the application on the employer's insurer not later than 7 days after the day the employer is served with the application.
(2) A party included as a third-party respondent must serve a copy of the notice including the party on the party's insurer not later than 7 days after the day the party is served with the notice.
Note Rule 3920 deals with including other parties.