Sayyiduna Abu Hurairah (may Allah be pleased with him) narrated from the Messenger of Allah (peace and blessings be upon him), he (peace be upon him) said: "If he has wealth, he will be freed from his wealth; if he does not have wealth, the slave will earn and obtain freedom."
Urwah narrated from this chain the same narration, and said: Regarding the share of the partner who did not free him: The slave will be told to earn and obtain his freedom himself.
Hadith Referenceمسند اسحاق بن راهويه / كتاب العتق و المكاتب / 477