Article 819-ter of the Code of Civil Procedure, applicable also to contractual arbitration (arbitrato irrituale) according to established doctrinal opinion, establishes the principle of parallel proceedings, whereby the pendency of a dispute before the ordinary court does not exclude the arbitrator's jurisdiction over the same dispute, allowing both proceedings to reach final judgment. This principle establishes the autonomy of arbitral proceedings in relation to any civil proceedings having the same subject matter.
The failure to raise the arbitration objection in ordinary proceedings does not automatically entail tacit waiver of the arbitration clause when the party, through conclusive conduct such as reference to the pendency of arbitral proceedings in procedural documents and repeated opposition to the termination of arbitral proceedings, unequivocally manifests the intention to obtain the arbitral award.