A party seeking grievance mediation must file a Petition for Grievance Mediation (OGM Petition). Arbitration disputes are final and legally binding at MDRS, a Massachusetts Abritration and Mediation firm in Boston and Salem.Arbitration is not a right, but rather, an agreement between the disputing parties. The filing requirements for Mass Arbitrations are set out in MA-2 of the Mass Arbitration Supplementary Rules. Arbitration involves a private, neutral person (or persons, in some instances) make what usually amounts to a final decision on your case. In the blank spaces provided for the claimants' names, you should write or type the name of each claimant filing the Statement of Claim. Attorney Referrals - Sweeney Merrigan Personal Injury Lawyers.