In other words, this new company would be a financial beer behemoth -- "the last piece," as Gatza called it, to a flurry of acquisitions that's been going on since the '90s.
Expect the federal government to do some anti-trusting
US regulators have traditionally been pretty attentive to the country's beer industry, and probably will be in this case, as Gatza hypothesized in a blog post. When ABI acquired Modelo, the DOJ required "a sell-off to Constellation Brands-Beer Divsion, so it is hard to think that they would allow absorption of Miller [brands]"
Wait, what? Aren't they buying Miller and its brands?
Well, yes. But they may not be permitted to keep those brands in the US. Like all global industries, Big Beer can get pretty confusing, but the basic idea is that in the event of an acquisition, ABI would probably be required by the federal government to divest itself of control of SABMiller's US component (MillerCoors) by selling it. To whom? "Molson Coors or other large international entities," guessed Gatza, including "Constellation Brands—Beer Division, Heineken or Carlsberg" or even non-beer conglomerates.