Malik said, "The generally agreed on way of doing things among usis that when slaves write their kitaba together in one kitaba, andsome are responsible for others, and they are not reduced anything bythe death of one of the responsible ones, and then one of them says,'I can't do it,' and gives up, his companions can use him in whateverwork he can do and they help each other with that in their kitabauntil they are freed, if they are freed, or remain slaves if theyremain slaves."Malik said, "The generally agreed on way ofdoing things among us is that when a master gives a slave his kitaba,it is not permitted for the master to let anyone assume theresponsibility for the kitaba of his slave if the slave dies or isincapable. This is not part of the sunna of the muslims. That isbecause when a man assumes responsibility to the master of a mukatabfor what the mukatab owes of his kitaba, and then the master of themukatab pursues that from the one who assumes the responsibility, hetakes his money falsely. It is not as if he is buying the mukatab, sothat what he gives is part of the price of something that is his, andneither is the mukatab being freed so that the price established forhim buys his inviolability as a free man. If the mukatab is unable tomeet the payments he reverts to his master and is his slave. That isbecause kitaba is not a fixed debt which can be assumed by the masterof the mukatab. It is something which, when it is paid by the mukatab,sets him free. If the mukatab dies and has a debt, his master is notone of the creditors for what remains unpaid of the kitaba. Thecreditors have precedence over the master. If the mukatab cannot meetthe payments, and he owes debts to people, he reverts to being a slaveowned by his master and the debts to the people are the liability ofthe mukatab. The creditors do not enter with the master into any shareof the price of his person."Malik said, "When people arewritten together in one kitaba and there is no kinship between them bywhich they inherit from each other, and some of them are responsiblefor others, then none of them are freed before the others until allthe kitaba has been paid. If one of them dies and leaves property andit is more than all of what is against them, it pays all that isagainst them . The excess of the property goes to the master, and noneof those who have been written in the kitaba with the deceased haveany of the excess. The master's claims are overshadowed by theirclaims for the portions which remain against them of the kitaba whichcan be fulfilled from the property of the deceased, because thedeceased had assumed their responsibility and they must use hisproperty to pay for their freedom. If the deceased mukatab has a freechild not born in kitaba and who was not written in the kitaba, itdoes not inherit from him because the mukatab was not freed until hedied."
USC-MSA web (English) reference: Book 39, Hadith 4