The requirement of specific written approval of the arbitration clause, pursuant to Article 1341, paragraph 2, of the Civil Code, is satisfied even in the case of numerical reference to multiple clauses, provided that such reference is accompanied by an indication, albeit summary, of their content, the onerous nature of the arbitration clause being thereby excluded.
With regard to the interpretation of the arbitration clause, doubt as to the actual intention of the contracting parties concerning the institutional or contractual (arbitrato irrituale) nature of the arbitration must be resolved in favour of the institutional nature, given the exceptional nature of the derogation from the rule whereby the award has the effect of a judicial judgment.
Indicators of the institutional nature of the arbitration include the use of expressions such as "shall decide according to law", the reference to rules intended to govern the powers of the arbitrators and the provision for application of the Code of Civil Procedure to the procedure to be followed, elements which manifest the parties' intention to give rise to a jurisdictional, albeit private, resolution of the dispute.
The relationship between the state court and the arbitrator must be characterised as a question of jurisdiction, with the consequence that the decision by which the court affirms or denies its jurisdiction in relation to an arbitration agreement takes the form of a judgment.