Oasis is buying Pabst with TSG, an investment firm known for its work with consumer products companies. [...] Pabst accounts for less than 3 percent of the U.S. beer market, said Eric Shepard, executive editor of Beer Marketer’s Insights, an industry tracker. In a statement, Oasis Chairman Eugene Kashper called Pabst Blue Ribbon the “quintessential American brand — it represents individualism, egalitarianism and freedom of expression — all the things that make this country great.”