Abstract: In biomedicine and neuroscience, researchers exclude female animal subjects from preclinical studies. As a result, they fail to consider sex as a biological variable while testing some drug or treatment. I begin by highlighting the problems associated with this exclusion (section 1.1) and ask whether this exclusion counts as an epistemic wrong, i.e., a wrong committed against someone in their capacity as an epistemic subject. I consider the proposal that the exclusion is an epistemic injustice to women patients and devote section 2 to show that this proposal fails. Moreover, I show that one cannot account for the exclusion as an epistemic wrong under Miranda Fricker’s (2007) framework, given her notion of epistemic subjectivity. To account for the intuition that the exclusion is an epistemic wrong, I briefly outline a broader notion of what it means to be an epistemic subject. In section 3, I explain that the exclusion is an epistemic wrong because it violates the epistemic claim-rights of women patients. In doing so, I use Lani Watson’s (2022) recent account of epistemic claim-rights. In 3.1, I defend the claim that women patients have an epistemic claim-right against researchers excluding female subjects from preclinical studies. Finally, in 3.2, I consider some important upshots of my thesis that the exclusion violates the epistemic claim-right of women patients.