The Harpoon Brewery, or Massachusetts Bay Brewing Company, grew out of a well received proposal at Harvard Business School. Rich Doyle and Dan Kenary cofounded Harpoon and started brewing in 1986. In 1987 a facility at 306 Northern Avenue, Boston, MA was opened. As of 2005 this facility is still the main brewery for Harpoon with a capacity of 60,000 barrels a year. In 2000 the Catamount Brewery was purchased in Windsor, VT. Initially Harpoon tried to revitalize Catamount by streamlining operations (Catamount went under because they upgraded to a state-of-the-art facility, then couldn't recoup that investment), but the beer did not sell so the Catamount name was retired and the brewery was given over to the production of Harpoon.

As of 2005 Harpoon produces ~100,000 barrels of beer a year and distributes to 22 states in the eastern half of the United States. This makes Harpoon a very large regional brewery. Roughly 70% of sales come from Harpoon IPA alone. Another 20% comes from UFO (UnFiltered Offering). Harpoon currently produces nine different beers.

  • Ale - An American Pale Ale (4.90% ABV) available year round, this was the first beer brewed by Harpoon in 1986.
  • IPA - An American IPA (5.90% ABV) available year round, this beer was originally Harpoon's Summer Seasonal in 1993.
  • Munich Dark - An American Brown Ale (5.60% ABV) available year round, this beer was introduced in 1998.
  • Winter Warmer - This Winter Warmer is a seasonal offering.
  • Hibernian Ale - This Irish Rad Ale is a seasonal offering.
  • Summer - This Kolsch style (5.50% ABV) is a seasonal offering.
  • Octoberfest - This American Amber/Red Ale (5.50% ABV) is a seasonal offering.
  • 100 Barrel Series - This limited edition beer is a different style brewed yearly in a single 100 barrel batch.
  • UFO Hefeweizen - An American Pale Wheat Ale (5.10% ABV) available year round, this beer is unique to the Harpoon line of beers since it uses a different strain of yeast.

Harpoon's slogan is 'Love Beer. Love Life. Harpoon.'