Bottled in Bond is a labeling term used on some spirits of the United States. It has several highly regulated attributes. First, the spirit must be a product of one distiller at one distillery and from one distillation season. Secondly, the spirit must be aged in a federally regulated warehouse under government supervision for at least four year. The proof of these spirits must be 100 (or 50% alcohol by volume). These standards were a part of the Bottled-in-Bond Act of 1897 in an effort to create a standard for quality bourbon in an age when so many spirits were highly tampered with, adulterated, and misrepresented to consumers. (Spirits/Classification & Attributes)