The dissemination and use of health data firstly questions the production of health data and, in particular, the production of health research data. In addition, talking about the openness of data also requires understanding how health data are produced at the scientific level and especially how the dissemination of this production has been regulated by the legislator. Finally, it should be remembered that health data, including health research data, are most often personal data, to which a legal data protection system applies which is currently governed in Europe by the General Data Protection Regulation.