In+hypothesis+of+arbitration+multipart+in++miss the agreement+on the+appointment+of the+referees,+the+procedure+started+a+part+part+si+trains+in+as many+procedures+how many are+the+parts,+salvo+that they exist+a ‘hypotheses+of+litisconsorzio+necessary,+in+presence+of the+which the arbitration+is+unprocessable.+and+vi+is+litisconsorzio+necessary+only+the+the+substantial situation+multi -subjective+deduced+in+judgment+Deb Ba+being+necessarily+decisive+in+unitary way+towards+comparisons+all+i+subjects+what+nor are they+partners,+like+in the+case+of+action+that+curtain+at+constitution+or+at+change+a+ratio+pluriso ratio GGETIVE+SINGLE;+not+appeals+instead a hypothesis+of+litisconsorzio+necessary+when+the+cause+has+ad+object+an obligation+solidarity,+since+the+creditor+has+title+of+demand+from+each+debtor+the whole.