This study provides conceptual clarity on open data users by connecting an empirical analysis of policy documents to emerging theoretical research on data publics. Releasing files to the public for reuse is the primary objective of policy on open government data. Recent public sphere scholarship provides insights into who reuses data by defining a data public as people who actively construct narratives with openly available digital sources. A content analysis of United States federal policy documents identified the language used to represent people who might reuse data. An inductive qualitative analysis of mandated digital strategy reports generated a taxonomy that characterizes people mentioned in open data policy. In addition to the taxonomy, this research contributes a set of propositions to predict data reuse based on these characteristics. The results encourage further dialog between public sphere and digital government scholars to establish testable explanations about data publics.