The criterion distinguishing arbitration, whether arbitration proper or contractual arbitration (arbitrato irrituale), from contractual expert determination (perizia contrattuale) lies in the waiver of the jurisdiction of the ordinary courts: where the parties intended to waive judicial protection, the clause is an arbitration clause and the expert determination constitutes an arbitration; failing that, a pure contractual expert determination is an atypical contractual arrangement which does not entail any waiver of jurisdiction.
A pure contractual expert determination clause creates only a contractual obligation to give effect to the outcome of the expert determination, where this is undertaken and brought to completion, and does not preclude judicial proceedings having as their subject matter also that part of the dispute entrusted to the expert.
A plea that the ordinary court lacks potestas iudicandi, founded on a policy clause requiring the prior conduct of a contractual expert determination, is therefore unfounded where that clause does not disclose any waiver by the parties of judicial protection.