Bourbon's legal definition varies somewhat from country to country, but many trade agreements require the name bourbon to be reserved for products made in the United States. The U.S. regulations for labeling and advertising bourbon apply only to products made for consumption within the United States; they do not apply to distilled spirits made for export. Canadian law requires products labeled bourbon to be made in the United States and also to conform to the requirements that apply within the United States. But in countries other than the United States and Canada, products labeled bourbon may not adhere to the same standards. For example, in the European Union, products labeled as bourbon are not required to conform to all of the regulations that apply within the United States, though they still must be made in the U.S.
The Federal Standards of Identity for Distilled Spirits (27 C.F.R. 5) state that bourbon made for U.S. consumption must be:
Produced in the United States
Made from a grain mixture that is at least 51% corn
Aged in new, charred oak barrels
distilled to no more than 160 (U.S.) proof (80% alcohol by volume)
Entered into the barrel for aging at no more than 125 proof (62.5% alcohol by volume)
Bottled (like other whiskeys) at 80 proof or more (40% alcohol by volume)