With one exception, the RFS program places no restrictions on the mixing of ethanol produced in different facilities, by different feedstocks, or through different processes. Also, RINs assigned to ethanol are fungible, in that a specific assigned RIN is not required to be transferred with the same gallon of ethanol until separation of the RIN.

RINs with a K code of 1 (assigned RINs) and volumes can be matched at the owner's discretion, so long as the requirements in 80.1428(a) are met. The one exception is for ethanol made at a foreign facility for which the foreign producer generated RINs and intends to export it to the U.S. In this case, the ethanol must be segregated from other volumes of ethanol. See 80.1466(d)(1)(vi).