Significant racial, socioeconomic, and geographic disparities in kidney transplantation persist despite significant efforts to change policies and promote access to transplantation. While revision of the kidney allocation system in 2014 was effective at mitigating racial disparities among waitlisted candidates (Fig 1A), additional questions remain. For example, it is unclear why Black candidates receive a higher proportion of kidneys from Black donors than would be otherwise expected (Fig 1B), and why Black deceased donor kidneys are associated with worse outcomes than kidneys from other racial groups.