The open data phenomenon is no longer a novelty. Many government bodies and public enterprises have systematized the opening up of their data by setting up digital publishing platforms, the management of which constitutes a sizable task in its own right. A review of the last ten years would appear to confirm the emergence of a new and lasting dynamic regarding the production, publication, and reuse of open data (Cardon 2019). However, this dynamic has brought with it a variety of new issues that are far from being resolved. Actors must still fulfill a variety of conditions in order to open up their data. The concept of open data can be traced back to 2010, with different social worlds each endowing the term with their own particular definition. Intimately linked to the history of computer science, open data was initially defined in legal terms, by applying the legal principles of free or open-source software to the publication of databases. Then, in the wake of the open access movement, which argued for the unhindered diffusion of knowledge in the scientific domain, open data was defined by the open government movement that emerged in the political arena as the application of the principles of transparency to democratic governance in the United States. These principles were later joined by a series of technical criteria proposed by the World Wide Web Consortium to define degrees of data openness based on the extent to which the data can be processed automatically by software from the semantic web…