Musannaf Ibn Abi Shayba 13:2694

Abu Bakr narrated to us, he said: Ad-Dahhak bin Makhlad narrated to us, from Ibn Jurayj, from ‘Ata’, regarding a man who gives money to a man for *mudarabah* (profit-sharing partnership), whether he is a guarantor: He said, "He is not a guarantor."