A test case may be advisable for a group of creditors raising claims against the same opponent. The questions which arise in this connection are not primarily of a civil procedural nature. Rather, it revolves around finding adequate agreements in the individual case, on the one hand among the group members and on the other hand with the opponent (vgl. Bläuer, Rechtsausübung durch Gläubigergruppen, Diss. Univ. Luzern, 2007, 119 ff.).