Industry 4.0 provokes a shift in the way production systems are designed and used that raises ethical questions. This shift stems from several features relevant to Industry 4.0, specifically the increase of the importance of the digital world and the fostering of the development of more autonomous and intelligent systems that will interact and interoperate with humans in more open production environments. The first aim of this paper is to study to what extent Industry 4.0 impacts ethics. The second one is to raise the awareness of researchers regarding potential ethical risks when designing and evaluating future Industry 4.0 compliant production systems. For that purpose, the ethical stakes of industry 4.0 are first presented. Then, an overview of related work is done to evaluate the different scientific fields potentially contributing to the study of the ethical dimension in Industry 4.0. A discussion is finally proposed from this overview. The main conclusion of this discussion concerns the urgent need to address the ethical dimension of scientific contributions relevant to Industry 4.0, given the lack of work in that field.