During and after the Napoleonic wars, European savants struggled to revamp their institutions and forms of life in the context of rapidly evolving political cultures and legal frameworks. The procedures, functions, and genres associated with scientific publishing constituted a particularly central site for these attempts at reinvention. In Britain and France, the scientific journal – a more or less new kind of publication with roots in the late eighteenth century – took on central roles in registering knowledge claims, adjudicating priority, and making up savants’ identities. This paper will focus on controversies over the role of print in priority disputes during 1840s. First, the problem of how best to mark discovery claims arose in France in a controversy between François Arago and Guglielmo Libri; this began as a disagreement over how to write the history of science, but expanded into a broad controversy over the status of the meetings of the Académie des Sciences after its public character had become associated with an official journal (the Comptes rendus hebdomadaires). These norms and procedures then became a matter of dispute between French and British savants over the discovery of the planet Neptune in 1846. At stake was the nature and bounds of the appropriate public for discovery claims, the relationship between discovery and other debates about intellectual property, and the politics of national and international cooperation in the sciences. This talk will focus in particular on the distinct ways in which debates regarding patent law reform in Britain and France inflected the changing meaning and mechanics of scientific priority.