Umayr (may Allah be pleased with him), the slave of Abu al-Lahm, relates: I was a slave. I asked the Messenger of Allah (peace and blessings be upon him): May I give charity from my master's wealth? He (peace and blessings be upon him) said: "Yes, and the reward will be for both of you."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7858