Advance ruling defines key terms governing binding decisions on proposed or undertaken GST supplies by applicants. Defines key terms for the Advance Ruling procedure: advance ruling means the decision by the Authority or Appellate Authority on questions relating to supplies of goods or services proposed or undertaken by the applicant; Authority and Appellate Authority denote the constituted bodies for issuing and reviewing rulings; applicant is a person registered or seeking registration under the Act; and application denotes the filing to the Authority to obtain a ruling.