What is the ruling concerning the validity of Ruqba?

Primary text

The Ruqba is interpreted as being the same as the 'Umra; it is a grant for the recipient's lifetime, and if the recipient dies first, it reverts to the giver. This is the opinion of 'Ali, and Al-Zuhri suggested it is a bequest. If the condition is that it returns to the giver if the recipient dies first, it is treated the same as an 'Umra where return is stipulated.