It is narrated from Sayyiduna Shaddad bin Aws (may Allah be pleased with him); he said: I was with the Messenger of Allah (peace and blessings be upon him) in the year of the Conquest of Makkah, and he (peace and blessings be upon him) passed by a man who was being cupped on the eighteenth or seventeenth of Ramadan, and he (peace and blessings be upon him) said: "The one who cups and the one who is cupped have both broken their fast."
Hadith Referenceالمعجم الكبير للطبراني / باب الشين / 7098