In 2014, Congress removed industrial hemp with a concentration of ≥0.3% tetrahydrocannabinol (THC) dry weight from the definition of marijuana in the federal Controlled Substances Act (CSA). Hemp production was authorized in a limited pilot program until 2018, when Congress passed the Agricultural Improvement Act (Farm Bill) that expanded the program to anyone licensed to produce hemp by the U.S. Department of Agriculture (USDA) or by a USDA-approved State or Indian tribe. Hemp’s greatest value is in two of its 80-plus molecules: cannabidiol (CBD) and THC. These molecules, present in all forms of Cannabis sativa L. (cannabis), including hemp, have medicinal and recreational uses. By removing hemp from the CSA, the Farm Bill altered the legal status of hemp’s extracts, including CBD and THC. In 2018, Epidiolex ® , the world’s first and only CBD-based medicine, was approved in the U.S. The drug was placed in Schedule V of the CSA to comply with an international drug treaty requiring control of cannabis and all its extracts. In April 2020, Epidiolex was removed from the CSA schedules. This occurred, according to the Drug Enforcement Administration (DEA), because with a THC content below 0.3%, Epidiolex no longer met the Farm Bill’s criteria as a controlled substance. This review discusses the Farm Bill’s hemp provisions and how they have affected the legal status of hemp derivatives CBD and THC. The review also discusses a loophole in the Farm Bill that decriminalizes the production of marijuana by negligent hemp farmers. In passing, we discuss how lobbying by the hemp/CBD industry influenced passage of the Farm Bill.