Nafi' (may Allah have mercy on him) narrates from Ibn Umar (may Allah be pleased with them both) that the mudabbar slave is freed out of the third (of the estate).
Al-Shafi'i (may Allah have mercy on him) said: Ali bin Zabyan told me: "I used to narrate it as marfu' (from the Prophet), but my companions said to me: 'It is not marfu'; it is mawquf on Ibn Umar.' So I narrated it as mawquf." And the hadith masters (huffaz) narrate it as mawquf on Ibn Umar.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المدبر / 21573
Nafi' narrates from Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "The mudabbar slave is freed out of the third (of the estate)."
The correct version is mawquf (Ibn Umar's own statement), as al-Shafi'i (may Allah have mercy on him) narrated it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المدبر / 21574
Abu Qilabah (may Allah have mercy on him) says that a man declared his slave free upon his own death (i.e., made him mudabbar), and the Prophet (peace and blessings be upon him) counted him against the third (of the estate).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المدبر / 21575
Imam al-Sha'bi (may Allah have mercy on him) narrates from Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) that he used to count him (the mudabbar) against the third (of the estate).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المدبر / 21576
Al-Hasan (may Allah have mercy on him) narrates from Ibn Mas'ud (may Allah be pleased with him) that he used to say: "He (the mudabbar) is freed out of his (master's) third."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المدبر / 21577