The Boston Beer Company gets even bigger by merging with rival Dogfish Head. (AP Photo/Charles Krupa)

ASSOCIATED PRESS

The craft beer business isn't the gentle marketplace that it used to be. More than 7,000 breweries are now fighting it out for a share of drinkers' refrigerators, while supermarket shelves abound with colorful labels and quirky flavors.

That helps explain why two of the most notable names in craft beer decided to join forces this week.

On Thursday, the Boston Beer Company and Dogfish Head announced a $300 million merger that will see Dogfish founders Sam and Mariah Calagione become the largest stakeholders in Boston Beer.

Both companies will continue to operate as independent brewers, according to the Brewers Association. Meanwhile, Sam Calagione will get a seat on board at Boston Beer, founded by effervescent beer industry CEO Jim Koch in 1984.

"We believe we are creating the most dynamic and diverse American-owned platform for craft beer and beyond," Koch said, in announcing the deal.

Added Calagione, "Mariah and I believe so much in the future of our combined companies that we're all in" and will re-invest nearly all the proceeds of their shares into Boston Beer.

Boston Beer, best known for its Samuel Adams Boston Lager, has always been on the lookout for beer trends and the latest flavors.

Back when the company was founded in 1984, it was simpler to be a leader. But now, microbreweries have popped up in every corner of the United States.