Vaccinomics encompasses a host of multiomics approaches to characterize variability in host-environment (including pathogens) interactions, with a view to a more directed or personalized use of vaccine-based health interventions. Although vaccinomics has the potential to reduce adverse effects and increase efficacy of vaccines, the use of high-throughput, data-intensive technologies may also lead to unanticipated discoveries beyond the initial aims of a vaccinomics study--discoveries that could be highly significant to the health of the research participants. How do clinician-researchers faced with such information have to act? What are the attendant legal duties in such circumstances and how do they differ from the duties of non-clinician researchers? Together with a critical analysis of the international laws and policies framing researchers' duties with regard to incidental findings, this article also draws from Quebec's civil law--with its rich jurisprudence on clinician and researcher liability--as a case study to evaluate the potential legal implications associated with vaccinomics investigations. Given previous lessons learned from other data-intensive sciences, the education of clinician-researchers with regard to their roles, limitations, and legal obligations remains an important strategy to prevent potential legal complications and civil liability in vaccinomics research in the postgenomics era.