"The Messenger of Allah ruled that pre-emption is to be given in everything that is shared in which the division is not clear, whether it is a house or a garden. It is not permissible to sell it before informing one's partner, who may take it or leave it, as he wishes. He (the share-owner) sells it without informing him, and then he has more right to it."
Reference: Sunan an-Nasa'i 4701 In-book : Book 44, Hadith 253 English translation : Vol. 5, Book 44, Hadith 4705
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