Sales of Bud Light and Budweiser dropped 24.6% and 9.2%, respectively, for the four weeks ended June 3 from a year earlier, while Modelo Especial sales rose 10.2%, according to consulting company Bump Williams, which sources data from NielsenIQ.

In May, AB InBev CEO Michel Doukeris said it was too early to have a full view of the impact from the backlash.

"Bud Light's stumble with Dylan Mulvaney will certainly hurt their chances to take market share, but Miller Lite, Coors Light and Modelo will reap most of those rewards," said Jon Reynolds, a certified instructor in the business of craft beer at the University of Vermont.

Constellation's Modelo Especial was the top-selling beer brand in the United States with an 8.4% share of overall beer sales through retail stores for the period ending June 3, Bump Williams data showed.

Bud Light came in second with a 7.3% share.

AB InBev's overall sales growth declined 12% in the four weeks ended May 20, data from NielsenIQ and TD Cowen showed.

TD Cowen analyst Vivien Azer said the decline would "fully capture the boycott," compared with the 3.6% decline in sales growth AB InBev witnessed for the four weeks ended April 22.

Shares of AB InBev had outperformed Molson Coors and Constellation Brands for the first three months of the year, but are now trending lower after the backlash against Bud Light intensified in April.

Even before the backlash, sales volumes of established "light" brands had slid at a faster pace than the U.S. beer sector as a whole over the past six years, according to Euromonitor International, as drinkers drifted to craft beers first and then to hard seltzers.

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