With the loss of Dernbach Castle, the feud was lost for the knightly house based there. On 21 May 1333 it concluded a contract with Henry III of Nassau-Dillenburg, in which it sold all of rights in the Herborn and the Herborner Mark and many other rights in smaller settlements. The Dernbachers retained only the religious patronage rights and 13 courts in smaller villages. In 1334 Henry III of Nassau-Dillenburg was finally given Wallenfels Castle by Landgrave Henry II. On 30 July, a contract was once more concluded between Nassau and the Dernbachers, in which questions about the rights from the first peace treaty were clarified. On 21 May 1336 an agreement was also concluded between the Lords of Bicken and Nassau, in which they sold Hainchen Castle  to the Count, but received rights to reign around Ebersbach. In 1350, the Lords of Dernbach, with the help of the Lords of Bicken in Hainchen and with the support of the Landgrave, built the castle of New Dernbach in the Hessian territory of Blankenstein . After the end of the feuds, the boundaries between Hessen and Nassau in the area were set, which remain still today as district boundaries. On 21 April 1486, a Heidenrich of Dernbach sold his remaining serfs in the Nassau area to the local count for a low price. With this, the Lordship of Dernbach was finally transferred to Nassau.
Question: What event finalized the Lordship of Dernbach being transferred to nassau?
Answer: Dernbach sold his remaining serfs | to the local count