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Using photoemission spectroscopy techniques, we show that oxygen intercalation is achieved on an extended layer of epitaxial graphene on Ir(111), which results in the “lifting” of the graphene layer and in its decoupling from the metal substrate. The oxygen adsorption below graphene proceeds as on clean Ir(111), giving only a slightly higher oxygen coverage. Upon lifting, the C 1s signal shows a downshift in binding energy, due to the charge transfer to graphene from the oxygen-covered metal surface. Moreover, the characteristic spectral signatures of the graphene–substrate interaction in the valence band are removed, and the spectrum of strongly hole-doped, quasi free-standing graphene with a single Dirac cone around the K̅ point is observed. The oxygen can be deintercalated by annealing, and this process takes place at around T = 600 K, in a rather abrupt way. A small amount of carbon atoms is lost …