Musannaf Ibn Abi Shayba 13:3108

Abu Bakr narrated to us, he said: Ubayd Allah ibn Musa narrated to us, he said: Sufyan informed us, from Jabir, from al-Sha’bi, regarding two men who entered into a partnership, and each of them brought out ten thousand, but they did not mix them. One of them worked with what he had, and it was lost. He [al-Sha’bi] did not consider him a partner [in the loss], and he said: The loss is upon the one who lost it, and there is nothing upon the other regarding it.