An American craft brewery is a small, independent, and traditional brewery where small means a production of less than 6 million [US beer] barrels per year. [1] A US beer barrel seems to be 177.348 liters so that we get slightly more than 7 million hectoliters. The largest German brewery produced 5.5 million hectoliters in 2002. [2] So US small is German largest plus 25%? Or did I make a mistake, is there yet another…
More practically, I'd say to look at microbrewery limits, which are 15,000 barrels/year.