All the beer you drink is owned by one company

Bottles of Budweiser and Miller Lite beer
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Bottles of Budweiser and Miller Lite beer

If you like cheap beer, then this is the merger for you.

Global megabrewer Anheuser-Busch InBev announced Tuesday that it had reached a tentative agreement to purchase its rival SABMiller for $104 billion. If it's finalized, it would be the fourth largest takeover deal in history and the biggest this year. That means that rival brews like Budweiser and Miller Lite would be sold by the same company.

AB InBev brews brands like Stella Artois, Beck's and Leffe. SABMiller makes Peroni, Leinenkugel's and Coors, through an agreement with Molson Coors Brewing Co.

The deal needs to be approved by regulators, and would make Belgium's AB InBev, the world's largest brewer, even bigger and would give it a jump in emerging markets. It could mean rising beer prices around the world. Together, the company would dominate global beer sales with nearly 30 percent market share, three times its next rival, Heineken.

One of London-based SABMiller's major selling points is that it offers AB InBev overseas expansion possibilities. Forty-three of SABMiller's 210 brands are in Africa, according to the company's website. Thirty are in Latin America.

The company has been positioning itself for expansion in the developing world for years. Revenues from Latin America for example have increased 6 percent on an annual basis over five years, and over 30 percent growth in international brands in the area, according to a recent earnings call.

Growth in beer consumption in Africa is also a driver for AB InBev. The continent is one of the world's strongest emerging markets for beer sales. It's forecast to make up 33 percent of SABMiller's total global sales in fiscal 2017, up from 18 percent in 2013.

One questionable spot in growth for the brewing behemoth may be China, where the economic slowdown threatens beer sales. AB InBev has a 16 percent market share in China, selling its global Budweiser, Corona and Stella Artois as well as regional Double Deer, KK and Jinling.

SABMiller co-owns Snow, of which 106.6 million hectoliters was consumed in China in 2014, according to The Wall Street Journal. That's 21 percent of the nation's beer consumption by volume and makes Snow the world's largest-selling beer. But intense competition there makes turning a profit tricky. While around 20 percent of SABMiller's sales by volume come from China, only 2 percent of its operating profit do.

The big beer brands have been in trouble for years. Consumers have increasingly chosen higher-end craft beers instead of the typical cans of Bud Light and Miller. Global consumption of wine and liquor also has increased and further displaced beer's dominance. Budweiser's market share in 2014 was down nearly 8 percent from 2012, according to figures from Beer Marketer's Insights.

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CORRECTION: Anheuser-Busch InBev announced Tuesday that it had reached a tentative agreement to purchase its rival SABMiller for $104 billion. The amount was misstated in an earlier version of this article.