Much of the climate justice discussion revolves around how the remaining carbon budget should be globally allocated. Some authors defend the unjust enrichment interpretation of the beneficiary pays principle (BPP). According to this principle, those states unjustly enriched from historical emissions should pay. I argue that if the BPP is to be constructed along the lines of the unjust enrichment doctrine, countervailing reasons that might be able to block the existence of a duty of restitution should be assessed. One might (...) think that the duty to provide restitution no longer has moral weight if many benefits were already consumed, if the particular benefits obtained from historical emissions cannot be transferred from one country to another, or if present members of developed countries framed their life plans based upon the expectation of continued possession of those benefits. I show that none of these reasons negate the duty to provide restitution. (shrink)