Is the mortgaging of an authorized slave's property valid when the property belongs to someone who would be freed upon the master's manumission?

Primary text

If an authorized slave mortgages something that belongs to an individual who would be freed upon the master's manumission, the mortgage is invalid. This invalidity stems from the fact that the item in the slave's possession is the property of the master. Once the master purchases the item, the slave effectively becomes free (in terms of ownership over that specific item, as it reverts to being the master's property).