The obligation to state reasons for an arbitral award, provided for by Article 823 of the Code of Civil Procedure, must be deemed satisfied even by a summary exposition of the grounds for the decision, the ground for nullity pursuant to Article 829, paragraph 1, No. 5 of the Code of Civil Procedure arising only when the statement of reasons is entirely absent or is so deficient as to prevent reconstruction of the logical reasoning followed by the arbitrators in reaching the decision.
The defect of contradiction in the award, as a ground for nullity pursuant to Article 829, paragraph 1, No. 11 of the Code of Civil Procedure, exists exclusively where there is a manifest and irremediable conflict between different parts of the reasoning which has causal effect on the operative part, or an internal contradiction in the reasoning such as to render the ratio decidendi incomprehensible.
An arbitration clause which provides for the award to be final and for the parties' waiver of every means of challenge to which they may waive by law precludes challenge for breach of the rules of law relating to the merits of the dispute, only the non-waivable grounds for nullity provided for by Article 829 of the Code of Civil Procedure remaining available.