(2) باب ذِكْرِ سِعَايَةِ الْعَبْدِ
Abu Huraira (Allah be pleased with him) reported Allah's Messenger (ﷺ) as saying:
The slave who is jointly owned by two persons, and is emancipated by one of them, (this one) has liability (upon him to secure complete freedom for that slave).
Reference: Sahih Muslim 1502
In-book reference: Book 20, Hadith 3
USC-MSA web (English) reference(deprecated numbering scheme): Book 9, Hadith 3580