The defect of potestas iudicandi of the college arbitration is detectable ex officio only if it is it derivi from the nullity of the clause bosser. In the hypothesis in the nullity derivi, instead, from nomins referee performed with different modes those agreed from parts or foreseen from the code of ritual, the irregular composition of the college arbitral can constitute reason of appeal exclusively if such irregularities it is previous exceptional in the course judgment arbitration.