The objection of lack of potestas iudicandi of the arbitrators, based on the nullity of the arbitration clause for lack of specific signature pursuant to Article 1341, paragraph 2, of the Civil Code, cannot be raised for the first time in proceedings to set aside the award by the party who itself initiated the arbitration proceedings and contested the objection of nullity of the clause raised by the opposing party, given that the judicial openings to overcoming procedural preclusions for the protection of the weaker contracting party do not legitimise the voluntary pursuit of double protection, allowing the activation of arbitration only to then challenge its nullity in case of unfavourable outcome.
The qualification as weaker contracting party, for the purposes of overcoming the preclusions under Articles 817, paragraph 3, and 829, paragraph 1, No. 1, of the Code of Civil Procedure concerning the nullity of the arbitration clause, cannot be argued solely on the basis of the content of the contract signed, but requires specific allegations concerning the pre-existing inferior position prior to the negotiation and the impossibility of making a different choice in deciding whether to conclude the contract containing the arbitration clause.
The assessment of the facts pleaded and the evidence acquired during the arbitration proceedings cannot be contested by means of proceedings to set aside the award for nullity, since such assessment is contractually entrusted to the institutional competence of the arbitrators; the defect of reasoning pursuant to Article 829, paragraph 1, No. 5, of the Code of Civil Procedure can be found only in cases where the reasoning is entirely absent or is so deficient as not to allow the understanding of the course of reasoning carried out by the arbitrators and the identification of the ratio of the decision adopted.
The equitable assessment of damages made by the arbitrators pursuant to Article 1226 of the Civil Code constitutes a decision according to law and not a judgment according to equity, so that the challenge which amounts to the mere assertion that a court-appointed technical expert report would have led to greater compensation, without alleging the violation of rules of law, is inadmissible in proceedings to set aside the award.