Familial disclosure of genetic information is an important, long-standing ethical issue that still gives rise to much debate. In France, recent legislation has created an innovative and unprecedented procedure that allows healthcare professionals (HCPs), under certain conditions, to disclose relevant information to relatives of a person carrying a deleterious genetic mutation. This article will analyse how HCPs in two medical genetics clinics have reacted to these new legal provisions and show how their reticence to inform the patients’ relatives on their behalf leads them to use this option sparingly.