Henryk IV Probus
According to the theory of historian Oswald Balzer, around 1287 and by inspiration of Archbishop Jakub of Gniezno, treaty of mutual inheritance was agreed on between Leszek II the Black, Henryk IV Probus, Przemysł II and Henry III of Głogów. Balzer's theory gained immense popularity among historians. This view is refuted by Władysław Karasiewicz and Jan Baszkiewicz. However, doesn't completely exclude the possibility that during this period an agreement could have been concluded between Przemysł II and Henryk IV Probus, evidenced by the fact that the Duke of Wrocław voluntary returned of lands Ołobock and Wieluń to Przemysł II in his will.