Musannaf Ibn Abi Shayba 13:1184

Abu Bakr narrated to us, he said: Ali ibn Mushir narrated to us, from Dawud, from al-Sha’bi, who said: A man lost a camel, and he found it with a man who had spent on it, fed it, and fattened it. They disputed before Umar ibn Abd al-Aziz, and he was at that time the governor of Medina. He judged in favor of the owner of the camel for his camel, and he judged against him for the expenditure. Al-Sha’bi said: That did not please me, and he said: The man takes his camel and there is no expenditure upon him.