Climate philosophers conceptualize ‘grandfathering’ as ‘emissions grandfathering’: past emission levels entitle to future emissions. With the notable but controversial exception of libertarian Luc Bovens (2011), they regard grandfathering as intrinsically, even if not instrumentally, unjust. Questioning both the standard dismissal and Bovens’s Lockean pro-argument, this article defends the intrinsic (albeit limited) fairness of grandfathering conceptualized as ‘resources grandfathering’: fossil resource creation entitles to future resources use. A threefold ‘social constructivist’ ethical argument for this position is developed. First, philosophers’ basic aversion to grandfathering, while consistent with their emissions-based understanding,...