Standard number of bottles in a case of wine. Surprisingly, no one seems to know why. Perhaps it’s because a dozen is thought to be one of the most primitive groupings: 12 apostles, months in the year, inches in a foot, Zodiac signs in the night sky, pairs of ribs in the human body, eggs in a carton. But the twelve-bottle wine case may soon be a memory. Several European countries have banned them as being too heavy and potentially injurious—replacing them with 6-packs.