27 C.F.R. § 5.88 – Bottled in bond.

(a) The term “bond,” “bonded,” “bottled in bond,” or “aged in bond,” or phrases containing these or synonymous terms, may be used (including as part of the brand name) only if the distilled spirits are:
1. (1) Composed of the same kind (type, if one is applicable to the spirits, otherwise class) of spirits distilled from the same class of materials;
2. (2) Distilled in the same distilling season (as defined in § 5.1) by the same distiller at the same distillery.
3. (3) Stored for at least 4 years in wooden containers wherein the spirits have been in contact with the wood surface, except for vodka, which must be stored for at least 4 years in wooden containers coated or lined with paraffin or other substance which will preclude contact of the spirits with the wood surface, and except for gin, which must be stored in paraffin-lined or unlined wooden containers for at least 4 years;
4. (4) Unaltered from their original condition or character by the addition or subtraction of any substance other than by filtration, chill proofing, or other physical treatments (which do not involve the addition of any substance which will remain in the finished product or result in a change in class or type);
5. (5) Reduced in proof by the addition of only pure water to 50 percent alcohol by volume (100 degrees of proof); and
6. (6) Bottled at 50 percent alcohol by volume (100 degrees of proof).
(b) Imported spirits labeled as “bottled in bond” or other synonymous term described above must be manufactured in accordance with paragraphs (a)(1) through (6) of this section and may only be so labeled if the laws and regulations of the country in which the spirits are manufactured authorize the bottling of spirits in bond and require or specifically authorize such spirits to be so labeled. The “bottled in bond” or synonymous statement must be immediately followed, in the same font and type size, by the name of the country under whose laws and regulations such distilled spirits were so bottled.
(c) Domestically manufactured spirits labeled as “bottled in bond” or with some other synonymous statement must bear the real name of the distillery or the trade name under which the distiller distilled and warehoused the spirits, and the number of the distilled spirits plant in which distilled, and the number of the distilled spirits plant in which bottled. The label may also bear the name or trade name of the bottler.