Sayyiduna Shaddad bin Aws (may Allah be pleased with him) narrates: In the year of the Conquest of Makkah I was with him (peace and blessings be upon him), and on the eighteenth or the seventeenth of Ramadan he (peace and blessings be upon him) passed by a man who was being cupped, and he (peace and blessings be upon him) said: "The cupper and the cupped have broken their fast."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8299