Sahih al-Bukhari Book 49, Hadith 9
That he used to give his verdict regarding the male or female slaves owned by more than one master,
one of whom may manumit his share of the slave. Ibn `Umar used to say in such a case, "The
manumitted should manumit the slave completely if he has sufficient money to pay the rest of the
price of that slave (which is to be justly estimated) and the other shareholders are to take the price of
their shares and the slave is freed (released from slavery)." Ibn `Umar narrated this verdict from the
Prophet.
The Prophet (ﷺ) said, "He who manumits his share of a slave and has money sufficient to free the remaining portion of that slave's price (justly estimated) then he should manumit him (by giving the rest of his price to the other co-owners)." Nafi` added, "Otherwise the slave is partially free." Aiyub is not sure whether the last statement was said by Nafi` or it was a part of the Hadith.
That the Prophet (ﷺ) said, "Whoever frees his portion of a (common) slave."