A clause compromissoria included in the general conditions of sub-contract agreements, referring all disputes relating to or connected with the contract to arbitration, is enforceable against a party that has signed the general conditions containing that clause; in opposition proceedings against an order for payment, such a clause establishes the lack of competence of the ordinary court over a counterclaim brought by the opposing party that falls within the subject-matter scope of the arbitration agreement.
Under art. 819 ter, co. 1, cod. proc. civ., the connection between the principal claim — brought by way of an order for payment against which no arbitration exception has been raised — and a counterclaim falling within the clause compromissoria does not justify the unified determination of both claims before the ordinary court; the court is accordingly required to declare its lack of competence in respect of the counterclaim alone, remitting the case to the investigatory phase for thnitorial claim only.