An arbitration clause contained in a contract entered into between entrepreneurs is not subject to the requirement of specific written approval provided for by Articles 1341 and 1342 of the Civil Code, where the contract does not qualify as a contract of adhesion, that is to say, it is not prepared to regulate an indefinite series of relationships by means of standard forms or forms usable in series, but has been drafted in contemplation of a single and specific contractual transaction, in respect of which the contracting party was able freely to assess the content and to request amendments.
The defect of reasoning in an arbitral award, actionable pursuant to Article 829, paragraph 1, No. 5, of the Code of Civil Procedure, in relation to Article 823 of the Code of Civil Procedure, does not have the same content as the analogous defect in a judgment of the ordinary court, but is identifiable only in those cases where the reasoning of the award is wholly non-existent, is so deficient as not to permit the identification of the ratio decidendi, or is characterised by the adoption of a line of reasoning which is wholly unacceptable on a dialectical plane, such as to result in a non-reasoning.
The assessment of the facts alleged by the parties and of the evidence adduced during the arbitral proceedings cannot be challenged by way of a challenge for nullity of the award, since such assessment is contractually remitted to the institutional competence of the arbitrators; it follows that a ground of challenge is inadmissible where, under the guise of a violation of law or a defect of reasoning, it contests the merits of the appraisal of the evidentiary findings made by the arbitral tribunal.
Non-observance of rules of law as a ground of nullity of an award pursuant to Article 829, paragraph 2, of the Code of Civil Procedure is admissible only if confined within the same limits as the violation of law which may be raised by means of an appeal to the Court of Cassation under Article 360, paragraph 1, No. 3, of the Code of Civil Procedure, to the exclusion of any review of the assessment of the facts and the evidence, which remains reserved to the arbitrators.
The nullity of an arbitral award for violation of the principle of adversarial proceedings must be assessed not from a formal standpoint, but by verifying whether there has been an actual impairment of the possibility to adduce and to contradict; accordingly, nullity must be declared only where, following the allegation of the defect, there is an indication of the specific prejudice which it has caused to the party's right of defence.