This article connects the previously isolated literatures on corporate citizenship and corporate political activity to explain how firms construct political influence in the public sphere. The public engagement of firms as political actors is explored empirically through a discursive analysis of a public debate between the mining industry and the Australian government over a proposed tax. The findings show how the mining industry acted as a corporate citizen concerned about the common good. This, in turn, legitimized corporate political activity, which undermined deliberation about the common good. The findings explain how the public sphere is refeudalized through corporate manipulation of deliberative processes via what we term corporate citizenspeak—simultaneously speaking as corporate citizens and for individual citizens. Corporate citizenspeak illustrates the duplicitous engagement of firms as political actors, claiming political legitimacy while subverting deliberative norms. This contributes to the theoretical development of corporations as political actors by explaining how corporate interests are aggregated to represent the common good and how corporate political activity is employed to dominate the public sphere. This has important implications for understanding how corporations undermine democratic principles.