To whom does the property of a Mukatab (a slave contracted for manumission) belong?

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The property of a contracted slave belongs to his master, unless the contract explicitly stipulates otherwise for the slave. This applies also to any female slave (sarriyah) or child the contracted slave possesses. This view is held by Al-Thawri, Al-Hasan ibn Salih, Abu Hanifa, Abu Yusuf, and Al-Shafi'i. The evidence supporting this is the Hadith stating, "Whoever sells a slave who possesses property, the property belongs to the seller unless the buyer stipulates it." The rationale is that manumission by contract (kitabah) is equivalent to a sale, and since the slave sold himself, nothing else enters the contract, such as his children or relatives. Furthermore, since both the slave and his wealth were the property of the master, when the contract applies to one (the person), the other (the property) remains in its previous status, just as if he sold him to a third party.