Selling books distributed by the Ifta' or the League or replacing their duplicates with other books
Is it permissible to sell the books that are given as gifts by Dar Al-ifta’ (House of Fatwa) or the Muslim World League in Makkah, or books that are given as Waqf (endowments) in general, whether there is a necessity to do this or not? Also, is it permissible to get many copies of the same book or deliberately request many copies, and then exchange the duplicates for books with other people?
It is not permissible to sell the books you mentioned or any other Waqf books. The owner of these books should either benefit from them themselves or give them to someone else who can, without receiving anything in return. It is not permissible to take more than a copy of the same book from the presidency or the Muslim World League through deception and lies. Exchanging Waqf books between seekers of knowledge, without receiving any compensation, is permissible depending on the need, as we do not know of anything wrong with that - if Allah so wills. This is because the intention here is to benefit and not receive any compensation. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.