Image source: Altria.

In the stock market's history, Altria Group (MO 0.91%) holds a key place. Even among the many long-lived companies whose shares trade publicly, Altria Group stands out for its long track record of rising share prices and ample dividend income. Yet there's one key reason why 2016 could be a breakout year for Altria, and it doesn't have anything to do with tobacco. Let's take a closer look at why 2016 could be Altria Group's best year yet.

Taking tobacco for granted
To be clear, tobacco will remain an essential part of Altria's overall success. Consolidation in the industry has helped Altria cement its leadership role atop the domestic tobacco market, and the company has seen market share for its two main brands climb. In the cigarette arena, Marlboro continues to perform well, and the Copenhagen brand of smokeless tobacco has also dramatically increased its share of that market.

Although building and maintaining brand awareness takes effort and money, Altria's labors to sustain and build on its most valuable brands have generated huge rewards over the years. In light of falling overall cigarette volume in the U.S. over the past several decades, Altria's ability to raise prices for Marlboro and its other cigarette lines has been the way that the company has generating bigger profits. That game plan has worked well for years, and investors can expect Altria to stick with it for 2016 as well.

Raise a glass to growth
Yet the real game-changer for Altria in 2016 will come from the beer market. Anheuser-Busch InBev's (BUD -0.27%) anticipated takeover of SABMiller will create a colossus in the industry if it goes through, and both companies are optimistic that they can surpass regulatory hurdles and get a deal closed in the second half of 2016.

The result of the deal from Altria's perspective will be transformative. In exchange for its 27% stake in SABMiller, Altria will end up with about a 10.5% stake in the much-larger Anheuser-Busch InBev. Moreover, the tobacco giant expects to end up with $2.5 billion in cash.

Perhaps most importantly, Altria will have a hand in the future direction that Anheuser-Busch InBev takes. Altria representatives will have two spots on the beer-maker's board of directors. That will help ensure the continued flow of income from Altria's investment in the company. In Altria CEO Marty Barrington's words, "Altria will continue to participate in the global brewing profit pool as a large and significant shareholder in what will be the industry's largest company."

Will the deal go through?
Some investors have been nervous that the competitive impact on the beer industry would prompt regulators to block Anheuser-Busch from buying SABMiller. Part of the appeal for Altria is that Anheuser-Busch will become an even bigger global giant in the industry than it is now, so Altria won't want Anheuser-Busch to give up too much to get a deal done.

Nevertheless, Anheuser-Busch's plans include divestitures of SABMiller assets in certain countries in which the two companies now have substantial overlapping market share, including the U.S., the U.K., the Netherlands, and Italy. Still uncertain is whether SABMiller will have to give up its stake in a key Chinese brewing company.

At this point, Altria looks like it will get most of the benefits of a full SABMiller/Anheuser-Busch merger without too many obstacles. Barring unforeseen intervention that would require further changes, the current structure of the deal retains plenty of the promise that a combined Anheuser-Busch InBev and SABMiller brings to the table.

Altria Group has already rewarded its longtime shareholders with returns that few other stocks can match. Yet even with that legacy behind it, Altria stands a good chance of making 2016 one of its best years ever for those investors willing to see the company's evolution toward a more diversified conglomerate continue.