What is the ruling on donating a partner's share in a restaurant to be an endowment (waqf) for the sake of Allah Almighty, with its proceeds being spent in His cause, and what are the implications of informing the partners and the wife about this, and is there zakat due on his share, and what should he do if the partners decide to close the project, and should he wait for the project to become stable before endowing it?

A waqf (endowment) is valid for every owned, transferable asset from which benefit can be derived while its essence remains, even if it is jointly owned (musha'). The waqf requires a verbal declaration (sigha) indicating the endowment, and it is recommended to publicize and document it. If the benefit from the waqf ceases, the endowed asset is sold, and its price is spent on a similar endowment or for the beneficiaries. Zakat (definition) (alms) is not obligatory on the endowed asset because it is no longer in the ownership of its original owner.