Anheuser-Busch InBev (NYSE:BUD) can still be left crying in its beer over its merger with SABMiller (NASDAQOTH: SBMRY) after a U.K. judge approved a plan to treat the brewer's small investors as a separate class of shareholders. Although it was Miller that proposed the split, the hurdle for approval of the deal has been set that much higher and the little guy now has the power to scuttle the acquisition.

A tale of two investors

Because A-B InBev chose to help tobacco giant Altria (NYSE:MO) and Colombian bottling company BevCo avoid a huge tax bill from the merger by giving them special privileges unavailable to the rest of Miller's investors, as well as ensure they would support the deal, there's been a howl of protest about the unequal treatment.

Where small Miller investors were just getting cash from Anheuser-Busch's offer, Altria and BevCo -- two shareholders that control some 40% of Miller's stock -- were also entitled to receive fractional shares of A-B stock that wouldn't trade on the stock exchange. They would receive 0.483969 restricted shares of A-B stock for every one share of Miller they owned, plus the cash. It was an emolument that angered many investors.

The deal also had the added problem of being devalued by the U.K.'s vote to leave the European Union. Although the so-called Brexit won't occur for several years, the British pound took a beating and Anheuser-Busch's $106 billion offer for Miller suddenly was worth only $100 billion, a level even Miller's management thought too low. Moreover, because Altria and BevCo were getting stock in addition to the cash, their deal was actually worth more than just the cash portion the rest of the shareholders were being forced to accept.

Maybe final, but hardly best

In response, A-B InBev raised its offer for Miller from 44 pounds per share to 45 pounds, or about $104 billion, but it created a new crisis by declaring the bid its "best and final offer." Under U.K. merger rules, that meant the offer couldn't be raised for at least six months. Shareholders such as Aberdeen Asset Management, one of the deal's most vocal critics, and which owns around 1% of Miller stock, still thinks the offer undervalues Miller.

Miller's board didn't necessarily disagree with that assessment, believing the revised offer put the valuation at the very lowest end of what it deemed acceptable, but because it had already invested so much time, effort, and money into completing the transaction, it voted to accept it.

However, because it acknowledged the decision was difficult to make, and because the terms and conditions of the offer had changed so much since originally proffered, Miller asked U.K. regulators to treat its two largest shareholders as a separate class of investor. That would allow the rest of Miller's shareholders to vote on the deal separately, and also lowered the threshold of total shares needed to reject the offer. Now 75% of Miller's small shareholders need to approve the deal, a much higher resistance level to get over.

In the hands of the people

A London judge agreed with Miller that the two classes ought to be treated differently, ruling, "I have jurisdiction to order a meeting of public shareholders to be summoned that does not include Altria and BevCo."

Both brewers are scheduled to hold shareholder meetings on September 28 when a vote will be taken. If investors approve the deal, Anheuser-Busch and Miller expect they'll be able to close the transaction by October 10, but with a lot of opposition still remaining even after the increased offer, there is too much uncertainty to predict how the vote will actually fall out.

The one sure thing is that the small investor, and not Altria and BevCo, will decide whether or not Anheuser-Busch InBev and Miller control 30% of the world's beer production.