The Messenger of Allah ﷺ said, "Whoever frees his share in a jointly owned slave is required to complete the slave's emancipation by paying a fair valuation."
أن رسول الله ﷺ قال: من أعتق نصيبا له في مملوك كلف أن يتم عتقه بقيمة عدل.
Ahmad narrated it in the Musnad (4451) from Hushaym, [who said], "Yahya bin Saeed informed us, from Nafi, from Ibn Umar," and he mentioned it. He also narrated it (5474) from Yazid bin Harun, who said, "Yahya informed us," adding, "But if he has no wealth with which to free the remainder, then what has been freed has taken effect."Muslim narrated it (1501) through Yahya bin Saeed and others, without giving its wording, referring it instead to the wording of Malik. As for Bukhari (2525), he mentioned it as a suspended narration after having brought out the hadith of Musa bin Uqba, from Nafi, saying, "It was also narrated by Layth, Ibn Abu Dhib, Ibn Ishaq, Juwayriya, Yahya bin Saeed, and Ismail bin Umaya, from Nafi, from Ibn Umar, from the Prophet ﷺ, in brief form."