THE FOUNDER of Budweiser’s brewing empire, Adolphus Busch, was one of America’s most remarkable imports. The youngest of 21 German children, he emigrated to America in 1857, married into an established brewing business and set about building one of the world’s biggest beer companies.

Among his many firsts, Busch is credited with founding America’s first national beer brand — Budweiser; with revolutionising the shipment of beer in refrigerated railway cars; and devising a method to pasteurise his beer to keep it fresh. He was also early to adopt bottling beer.

Today Anheuser-Busch is the biggest brewer in America. Its brands account for 50.9% of all beer sold, and his descendants still run the company — but for how long? A takeover battle is brewing between Anheuser-Busch and Belgian rival InBev that could end the Busch dynasty’s control.

Dynasties and businesses have made uncomfortable bedfellows in recent years as firms once tightly controlled by families have fallen to outsiders. Last month Bill Wrigley, the great-grandson of the chewing-gum company founder, sold out to Mars after 117 years of family rule. Last year the Hilton family sold their stake in the hotel chain and News Corp, owner of The Sunday Times, convinced the Bancroft family to sell their media firm, Dow Jones.

If InBev makes a $46 billion (£23 billion) offer, it will have to convince shareholders, such as Warren Buffett, the world’s richest man, that Budweiser’s future is no longer a family affair. The Busch family have a minority stake in the company but a strong grasp on its board. So far, August Busch IV, who took over the helm of the so-called King of Beers in late 2006, is standing firm and has rejected talk of a takeover. His father, August III, is similarly set against a deal.

At least one family member, Adolphus IV, has said he is not against a deal. With only 4% of the business under their control, the Busches may struggle to fend off an attack.

InBev has yet to comment on a merger, which is, appropriately, coming out by leaks and drips, although it is no secret that InBev, brewer of Beck’s and Stella Artois, has wanted to do a deal with Budweiser for years.

“The leaks that have come out so far are all pretty detailed. It makes you think there may be fire beneath the smoke,” said Harry Schumacher, editor and publisher of Beer Business Daily. He said the possibility of a deal was “pretty likely”.

“The dollar is so cheap against the euro, Anheuser’s stock is so low and sales are flat. This is really the time to do it,” he said.

Adolphus agrees. “A possible merger is not a family issue,” he said last week. It is not “a matter of family solidarity or legacy. It is strictly a matter of shareholder value. It is no secret that the sluggish performance of the stock is a concern.”

Pressure has mounted on both Anheuser and InBev since rival brewers clinched big deals. Last November SAB Miller’s acquisition of Grolsch helped to grow the London-listed company’s presence in mature beer markets. In the US, SAB Miller is in the process of combining Miller Brewing with Molson Coors, America’s third-biggest brewer, putting more of a squeeze on Anheuser-Busch.

Meanwhile, in the US and western Europe the overall beer market has been flat, with sales in America growing at an annual 1% in recent years. Sales of beer from micro-breweries and so-called craft beers are rising at a brisk pace in the US, roughly 12% last year alone. Beer sales are also soaring in fast-growing economies such as Russia and China. With so much of its business tied to the US market and its big brands, Anheuser is in danger of looking fusty.

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