27-year-old wannabe Kweku Adoboli was running $50bn of bets on behalf of UBS, a bank whose shareholders' funds had recently reduced by an unfortunate series of accidents to a sum not much larger than the amount Adoboli was playing with. Then he was sick all over the management's shoes. Sick, sick sick. $2.3bn of sick. Whose fault was that?
For three years, Adoboli ran his own operation inside UBS. He called it the "Umbrella". Its results never appeared on management reports, except when it suited him to leak some Umbrella profit into the results he was reporting. Adoboli's immediate manager knew all about the Umbrella. "Thank f*** for your umbrella", he quipped in a casual email.