وَعَنْهُ; «أَنَّ رَسُولَ اَللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ نَهَى عَنْ بَيْعِ اَلْوَلَاءِ، وَعَنْ هِبَتِهِ»
The Messenger of Allah (sallallahu alayhi wa sallam) forbade selling or giving away the right of inheritance from a freed slave.
Bulugh al-Maram 908, Book 7, Business Transactions, Hadith 19. 1 min read