Musannaf Ibn Abi Shayba 13:2696

Abu Bakr narrated to us, he said: Ghundar narrated to us, from Ash'ath, from al-Hasan, that he was asked about a man who gave money to a man as a *mudaraba* (profit-sharing partnership) and made him guarantee it. He said: The profit is between them, and no attention is to be paid to his guarantee.