Profit-with-purpose corporations (PPCs) are new corporate forms that include a commitment of social or environmental nature in their by-laws, and that aim at better considering stakeholder interests. Because of its binding nature, we expect that a purpose may freeze institutional logics within PPCs. But what happens when the purpose is formulated as an innovative goal? The study is based on a historical case of PPC: La Poste, an incumbent company of public service in France. Our work reveals important phenomena with strong implications: the case indicates that a generative purpose leads to a systematic effort to designate new concepts that precisely call for the construction of new institutional logics.