When the term microbrewery had scarcely entered the vocabulary, Rich Doyle saw possibilities. Almost three decades ago, he became a co-founder of the Boston-based Harpoon Brewery, which has grown into the 12th-largest craft beer maker in the country.
Last July, with a stake of at least 40 percent in the business, he sensed it was the moment to make another move. He asked his partners to bring in an investor so the brewery could buy faltering competitors. And when they declined, he cashed out.
