The Messenger of Allah ﷺ said, "Whoever frees his share in a jointly-owned slave is responsible for freeing the slave entirely, provided he has wealth equal to the slave's value. The slave is to be valued at a fair price, and the partner is paid accordingly. If he has no wealth, then only the portion he freed is freed."
حدثنا ابن نمير ومحمد بن عبيد قالا حدثنا عبيد الله عن نافع
عن رسول الله ﷺ قال من أعتق شركا له في مملوك فعليه عتقه كله إن كان له مال يبلغ ثمنه قوم عليه قيمة عدل فإن لم يكن له مال عتق منه ما عتق
Its isnad is sahih, it is an abridgment of 5920, and a fuller version appears at 6038. "Muhammad bin Ubayd" appears in H as "Muhammad bin Ubaydullah," which is a clear error, while the correct form is confirmed in K and M. As for the addition of the word "[upon him]," we have added it from K and M, since it was not mentioned in H, and including it is the correct reading.