Respect for autonomy is a central moral principle in bioethics. It is sometimes argued that authenticity, i.e., being “real,” “genuine,” “true to oneself,” or similar, is crucial to a person’s autonomy. Patients sometimes make what appears to be inauthentic decisions, such as when (decision-competent) anorexia nervosa patients refuse treatment to avoid gaining weight, despite that the risk of harm is very high. If such decisions are inauthentic, and therefore non-autonomous, it may be the case they should be overridden for paternalist reasons. However, it is not clear what justifies the judgment that someone or something is inauthentic. This article discusses one recent theory of what justifies judgments of inauthenticity. It is argued that the theory is seriously limited, as it only provides guidance in three out of nine identified cases. There are at least six authenticity-related problems to be solved, and autonomy theorists thus have reason to engage with the topic of authenticity in practical biomedicine.