Many Wall Street analysts believe Pfizer will decide to split late next year, after compiling three years of financial data treating its “established products” division, which sells generic medicines, and its “innovative” patent-protected medicines unit, as if they were separate companies. “This would be the creation of two companies really, not one huge $350 billion Pfizer,” Andy Summers, co-portfolio manager at Janus Capital Group, said of the likely Pfizer split post merger.