Over the years a number of countries have abolished anonymous gamete donation and shifted toward open-identity policies. Donor-conceived children are said to have a fundamental “right to know” the identity of their donor. In this article, we trace the arguments that underlie this claim and question its implications. We argue that, given the status attributed to the right to know one’s gamete donor, it would be discriminatory not to extend this right to naturally conceived children with misattributed paternity. One way to facilitate this would be through routine paternity testing at birth. While this proposal is likely to raise concerns about the conflicting interests and rights of other people involved, we show that similar concerns apply to the context of open-identity gamete donation. Unless one can identify a rational basis for treating the two groups differently, one’s stance toward both cases should be the same.