Muwatta 1956

Malik says: the practice among us about a group who buy goods, cloth or slaves, and a man hears of it and says to one of them: I have heard the nature and the state of the cloth you bought from so-and-so; would you accept that I profit you by so much on your share? He says yes. He profits him, and becomes a partner of the group in his place. When he looks at it, he finds it ugly and overpriced. Malik said: that binds him, and he has no option in it, if he bought it according to a known sample and description. ¹

Belongs to the Muwatta, Book of Sales. Source: the Muwatta. Mentions Malik ibn Anas. Built on in the chapters on sale.