Kweku Adoboli, who is standing trial accused of bringing Swiss bank UBS to the brink of collapse, lost so much of his own money spread betting he had turned to Wonga.com and a string of other payday lenders, the jury was told.
Southwark crown court heard that Adoboli, 32, opened an account at IG Index, a spread betting firm that allows customers to make bets on financial instruments in March 2010. In the year running up to his arrest last September he lost £123,000 and was issued with two warnings by his bosses for failing to declare the account, which breached the banks rules. He had also opened a second spread betting account at City Index.
Adoboli's personal bank accounts were mostly overdrawn despite his £360,000 annual salary.
The account showed a string of payments to Wonga.com, Moneybox.com, Wageday Advance, Payday UK, Pounds to Pocket and three other payday lenders.
His bank account also shows his monthly salary payments increased from £2,886.66 in October 2008 to £6,176.69 in October 2010.
Adoboli, who worked for UBS's Delta One trading desk, denies two charges of fraud and two of false accounting dating back to 2008.
Earlier in the trial at Southwark crown court, Sasha Wass QC, for the prosecution, said the Nottingham graduate had "fraudulently gambled" the bank's money away in an attempt to boost his status and become one of the elite circle of City traders who earn vast annual sums.
A series of text exchanges on 1 June 2011 that were discovered on Adoboli's Mac Book Pro were read out to the court as part of the list of agreed facts.
One read: "Yeah, still at work, having to explain how we made so much money."
The reply reads: "I hope in a good way, or are you being accused of theft?", which is met with: "Haha, no!" followed by "On days like this, that is an amazing P+L [profit and loss] so we have to explain how it was done."
Another message continues: "I have always been very vocal about my view of the world. We expect to do well just not this well. 5m in one day is a big day but even when we lose 10% of our yearly profits we have to explain it."
Adoboli is accused of using a secret "pot of gold" hidden in umbrella funds to disguise unauthorised trades from supervisors. Richard Evans, an expert in equity and trading, who yesterday was called to assist the court, said he believed the umbrella funds were used in this way.
Asked by Wass whether anyone "higher than traders" would have known about it, he replied: "I don't believe so."
Wass asked: "In your experience, is it ever legitimate for a trader to secretly hide losses in a secret fund?" And he replied: "No."
During evidence in chief, he said the only people who would amend a settlement or information about a trade would be "the person who knew of the transaction, who would be the trader."
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