Regional craft beers are being brewed across the United States, but one company has paved the way: Samuel Adams brewer Boston Beer Co.
According to the Brewers Association, a trade organization, a craft beer must have an annual production volume of 6 million barrels or less. It can't be owned by a brewery that's 25 percent or more owned or controlled by an alcohol-related company that's not a craft brewer. It can't be produced with lightening ingredients like corn or rice.
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But just a few years ago, the volume part of that definition was 2 million barrels a year. When Sam Adams production tipped over that level, however, that requirement changed, noted IBISWorld analyst Hayden Shipp.
"The largest craft brewery and the one that sort of dictates how the industry is defined as far as volume is Sam Adams, or the larger company Boston Beer Co.," Shipp said. "And you also have Sierra Nevada bringing in No. 2 and these are breweries that have a presence throughout the United States as well as foreign markets and they're looking to expand further."
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Sam Adams went over the 2 million barrel mark and last year it sold more than 2.7 million barrels, according to a company financial statement. And if Boston Beer ends up producing more than 6 million barrels, the definition of craft beer is likely to change again, Shipp said.
If the definition of "craft beer" excluded Sam Adams, the market share growth trajectory of the entire craft beer industry as a part of total beer sales would be skewed, according to the Brewers Association.
And as the craft beer industry grows, it's only fitting that the volume limits that determine what's defined as a craft beer should grow as well, the industry association figures.
But Shipp said there's a historical context that's keeping Boston Beer in the craft beer fold as well.
"They are a special case. They are one of the sort of founders of this [craft beer] movement," and its growth has paved a path for industrywide growth, Shipp said.
Boston Beer operates several breweries in the United States, while other craft breweries like Sierra Nevada Brewing and New Belgium Brewing are just starting to expand beyond their original facilities, according to IBISWorld.
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What's more, Sam Adams' founder, Jim Koch, is also a sort of craft beer figurehead, Shipp said.
Currently, craft beer sales growth is estimated at 10.9 percent annually and craft brewers will have raked in about $3.9 billion by the end of this year, according to IBISWorld.
Boston Beer has about a 19 percent share of the craft beer market, according to IBISWorld. This year, analysts expect the company to sell $759.4 million worth of beer.
The second-largest craft brewer is Sierra Nevada, which has 5 percent share of the craft beer market. Sierra Nevada is expected to sell about $200 million worth of beer this year, according to IBISWorld estimates.