Declaratory action seeking nullity of a resolution appointing an arbitrator, filed against the Arbitration and Mediation Center of Amazonas. Preliminary injunction suspending the arbitration proceedings. Interlocutory appeal filed by the arbitration center seeking the granting of a stay of execution to resume the arbitration proceedings. Full granting of the requested stay, in view of the presence of fumus boni juris and periculum in mora. Recognition of the arbitration center's lack of standing to be named as respondent in the lawsuit. Standing to be a party, which is exclusive to those who contend in the arbitration proceedings: