The prices of renewable identification number (RIN) credits—the compliance mechanism used for the Renewable Fuel Standard (RFS) program administered by the U.S. Environmental Protection Agency (EPA)—sharply increased through April of this year, and they are now higher than at any time during the 13-year history of the RFS program. Rising global demand for the agricultural feedstocks used to make corn fuel ethanol and biomass-based diesel fuels has driven fuel ethanol and biomass-based diesel prices higher in 2021, pushing their corresponding RIN prices to new highs.