Is it permissible for a father to grant all his wealth to his daughters through sale and purchase contracts, thereby disinheriting his nephews, and what is the verse that stipulates the inheritance of nephews?

It is permissible for a father to gift his money to his children. Such a gift is valid if he gives them possession of it during his lifetime and health, and they dispose of it. However, it is not appropriate to do so as a stratagem to disinherit some heirs, and this is forbidden. Stratagems that lead to nullifying rights are not characteristics of believers. Scholars have explicitly stated the prohibition of stratagems because they are actions of the Jews. If the giver intends, by his gift, to disinherit some heirs, this is forbidden. An example of this is a man gifting his money to his daughters with the intention of disinheriting his nephews, who are among the heirs, based on the saying of the Prophet, peace and blessings be upon him: "Give the shares to those who are entitled to them, and whatever remains is for the nearest male relative."