What is the ruling when a master's mortgaged slave injures another slave belonging to the same master who is not mortgaged?

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If the injuring slave is not mortgaged, the ruling follows that of injury inflicted upon the master's own property. The master has the right to Qisas (retaliation) if the injury warrants it. If the master forgives for financial compensation (Diyya) or the injury does not mandate Qisas, the injury is considered without legal consequence (hudar). This applies equally if the injured slave was a Qan (purchased slave), Mudabbar (a slave promised freedom upon master's death), or Umm Walad (a slave who bore the master a child).