Art. 829, co. 3, cod. proc. civ., as recast in 2006, applies to all arbitrations commenced after the entry into force of the reform, but, in order to establish whether a challenge for breach of the rules of law governing the merits of the dispute is admissible, the law to which that provision refers is to be identified as the law in force at the time the arbitration agreement was concluded; accordingly, in the case of an agreement under the general law concluded before the new rules, in the absence of any stipulation by the parties the challenge to the award must be regarded as admissible, unless the parties had authorised the arbitrators to decide ex aequo et bono or had declared the award not open to challenge.
A reference in the arbitration clause to the award being final does not constitute an unequivocal expression of an intention to exclude the possibility of challenging it for breach of rules of substantive law.
The defect of lack of reasons which may be relied upon in challenging an award amounts to a formal defect of absence of reasons, which exists only where the reasons are wholly lacking or are so deficient as not to allow the logical reasoning leading to the arbitral decision to be understood, or where they contain irreconcilable contradictions within the body of the reasons or of the operative part such as to render the ratio decidendi unintelligible; insufficiency of reasons on a particular point of the dispute cannot therefore be relied upon.