When Marcel Ospel was forced out as chairman of UBS in April, his successor, Peter Kurer, penned a paean to the man who oversaw the Swiss financial titan's ill-starred foray into the world of investment banking: He called him the "architect of the modern UBS".

Now, as UBS prepares to announce its second-quarter results on Tuesday, one of the biggest questions facing the bank is just how much of Ospel's legacy Kurer and chief executive Marcel Rohner plan to undo.