The Messenger of Allah ﷺ gave judgment about the slave who had made an agreement to purchase his freedom (mukatab) and he had been killed that blood-wit is paid for him at the rate paid for a free man so far as he has paid the purchase money, and at the rate paid for a slave as the remainder is concerned.
قَضَى رَسُولُ اللَّهِ ﷺ فِي دِيَةِ الْمُكَاتَبِ يُقْتَلُ يُودَى مَا أَدَّى مِنْ مُكَاتَبَتِهِ دِيَةَ الْحُرِّ وَمَا بَقِيَ دِيَةَ الْمَمْلُوكِ