[ULPIANUS libro uicensimo ad edictum. ] §17.2.41.prSi quis a socio poenam stipulatus sit, pro socio non aget, si tantundem in poenam sit, quantum eius interfuit.
[ULPIANUS in his twentieth book on the Edict.] If anyone has stipulated for a penalty from his partner, he will not bring the action *pro socio*, if the amount of the penalty is as much as his interest.