Traditional demands of francophone minority communities in Canada target access to public services and the management of institutions in their language. These demands are legitimated by the Official Languages Act of Canada and are usually formulated in legal terms. A recent battle carried out in municipalities in Ontario and New Brunswick to legislate the language of commercial signage displaced the debate and made linguistic landscape a new stake in struggles for community recognition. This text will study the case of the Greater Moncton area to show some of the structural dynamics of linguistic cohabitation that were made visible through this debate, namely the role of social sciences in a bilingual context.