Editor's note: This article has been corrected. AB InBev's revenue rose 7.2% year over year in Q2.

Bill Gates said in 2018 that he wasn't "a big beer drinker." However, he appears to now qualify as a big beer investor. 

The Bill & Melinda Gates Foundation Trust manages the huge endowment that the multibillionaire made to the Bill & Melinda Gates Foundation. The trust revealed in a recent regulatory filing to the U.S. Securities and Exchange Commission (SEC) that it invested heavily in beleaguered Bud Light maker Anheuser-Busch InBev (BUD 0.12%). Here's why that big bet could pay off.

Two bottles of beer on the wall

At some point in the second quarter, the Gates Foundation Trust scooped up more than 1.7 million shares of Anheuser-Busch InBev. At the end of Q2, that stake was worth nearly $96.6 million.

This wasn't the first time that Gates' trust poured a lot of money into a beer stock. Earlier this year, it bought 4.18 million shares of Heineken Holding N.V. (OTC: HKHHF), which is the controlling shareholder of Heineken (OTC: HEINY).

Gates also personally invested in Heineken at the time, buying 6.65 million shares. The combined position, including Gates' individually owned shares and the Bill & Melinda Gates Foundation Trust's shares, was worth around $902 million. It's uncertain at this point if the Microsoft co-founder has put any of his own money on the line with AB InBev. 

Lights out?

Both AB InBev and Heineken lagged the overall stock market so far this year. However, the former's dismal performance received much more publicity.

Around five months ago, Bud Light sent some cans of beer to social media influencer Dylan Mulvaney. Mulvaney posted a picture with the Bud Light cans on Instagram. And it ignited a firestorm. 

Some Americans began boycotting Bud Light because they felt that the connection with Mulvaney promoted the transgender movement. (Mulvaney is transgender.) Fox News and other right-wing media outlets ran with the story. A video of singer Kid Rock shooting Bud Light cans went viral. Country singer Travis Tritt banned the beer from being sold at his tour sites.

For over 20 years, Bud Light reigned as the top beer (by sales) in the U.S. By June, the boycott caused it to slide into second place. AB InBev reported North American volumes declined by 14% year over year in the second quarter with sales falling by 10.5%. CEO Michel Doukeris acknowledged the lower numbers were due to the Bud Light boycott.

Why Gates' big bet could pay off

With this background, it might seem as if the Gates Foundation Trust made a poor investment by buying shares of AB InBev. However, the big bet could pay off for three key reasons. 

First, there are some signs that the negative impact of the boycott could be waning. Deutsche Bank conducted a survey last month to gauge the mindset of beer drinkers. It found that the percentage of respondents who say they're very unlikely to buy Bud Light plunged from 18% in July to 3% in August. Also, 19% of survey respondents said they were no longer buying Bud Light, down from 21% in the previous month. 

Second, AB InBev seems likely to avoid stirring up controversy going forward. Doukeris said in the Q2 conference call that its own survey found that consumers "want to enjoy their beer without a debate" and want Bud Light "to focus on beer" and "concentrate on the platforms that all consumers love." He indicated that AB InBev is taking this feedback to heart.

Third, the company's overall business remains solid. Even with the Bud Light boycott weighing on growth, AB InBev's revenue rose 7.2% year over year in Q2. Its North American market share has also been stable since late April. Any uptick in customers returning to Bud Light should provide a boost to AB InBev.