Is it permissible for an individual to bequeath the usufruct of a commercial project he owns to his wife, so that the returns are exclusively hers throughout her life, to the exclusion of other heirs?

If the husband grants the usufruct or income of a project to his wife for the duration of her life, there is no religious impediment to that. This is known among scholars as al-umra (life grant), and it is permissible for the wife and others. If the grantee dies, the usufruct returns to its original owner if he is alive, or to his heirs if he has passed away. However, if it is a will to be executed after death, it is not valid for an heir nor for more than one-third of the estate, unless approved by the heirs.

We would like to emphasize that matters of inheritance are delicate and complex, and it is not sufficient to rely solely on a fatwa. Rather, they must be brought before the Sharia courts for investigation and consideration.