The commitment of the European Union (EU) to Corporate Social Responsibility (CSR) is projected into EU law about annual reporting by businesses. Since EU member states further develop this framework by their own domestic laws, annual reporting with CSR information is not unified and only partially mandatory in the EU. Do all European businesses report CSR information and what public declaration to society do they provide with it? The two main purposes of this paper are to identify the parameters of this annual reporting duty and to study the CSR information provided by the 10 largest Czech companies in their annual statements for 2013–2017. Based on legislative research and a teleological interpretation, the current EU legislative framework with Czech particularities is presented and, via a case study exploring 50 annual reports, the data about the type, extent and depth of CSR is dynamically and comparatively assessed. It appears that, at the minimum, large Czech businesses satisfy their legal duty and e-report on CSR to a similar extent, but in a dramatically different quality. Employee matters and adherence to international standards are used as a public declaration to society more than the data on environmental protection, while social matters and research and development (R&D) are played down.