Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) said: A mudabbar slave will be freed only from the one-third (of the estate of the deceased).
Hadith Referenceسنن دارمي / من كتاب الوصايا / 3305
Saeed bin Jubair (may Allah have mercy on him) said: A slave who is set free after death will be freed from the entire wealth. The narrator said: Imam Abu Muhammad Darimi (may Allah have mercy on him) was asked: What is your opinion? He said: He will be freed from one third of the wealth.
Hadith Referenceسنن دارمي / من كتاب الوصايا / 3311