The Financial Conduct Authority (FCA) has hit Barclays with a £284 million fine - the UK's biggest ever financial penalty - for failings in its foreign exchange (FX) business.
The FCA said the bank's failings had "undermined confidence in the UK financial system… putting its integrity at risk."
The total fine of £284,432,000 is the largest financial penalty ever imposed by the FCA, or its predecessor the Financial Services Authority (FSA).
But the bank is paying out a total of £1,533 million in fines as it has also had to settle with the US Commodity Futures Trading Commission, the New York State Department of Financial Services, the U.S. Department of Justice, and the Board of Governors of the Federal Reserve System.
The FCA partnered with the US regulators to launch a joint investigation into the bank's FX business. Those US regulators and authorities have also imposed fines on Royal Bank of Scotland, Citigroup, JP Morgan, and UBS for FX rigging.
In total, the five banks are facing financial penalties of £3.7 billion.
The FCA found that between 1 January 2008 and 15 October 2013, Barclays' did not police its FX business adequately, meaning traders were allowed to put Barclays' interests ahead of those of its clients. Traders inappropriately shared information about client activities and tried to manipulate currency rates, colluding with traders at other firms in the process.
Georgina Philippou, the FCA's acting director of enforcement and market oversight said: "This is another example of a firm allowing unacceptable practices to flourish on the trading floor. Instead of addressing the obvious risks associated with its business Barclays allowed a culture to develop which put the firm's interests ahead of those of its clients and which undermined the reputation and integrity of the UK financial system.
"Firms should scrutinise their own systems and cultures to ensure that they make good on their promises to deliver change."
Barclays' traders communicated with traders from other firms in online chat rooms, describing themselves as "the players". The FCA said one trader called himself and his friends "the 3 musketeers".
They rigged currencies to ensure the rate at which Barclays had agreed to sell a particular currency to its clients was higher than the average rate at which it had bought that currency in the market to ensure a profit for the firm.
Had Barclays not settled the fine with the FCA when it did, it would not have received a 20% discount in penalty and would have faced a fine of £355 million. We have worked closely with other regulators in the US on this case including the Commodities Futures Trading Commission (CFTC), the Federal Reserve Bank of New York, the New York State Department of Financial Services (NYDFS), and the U.S. Department of Justice (DOJ).
Antony Jenkins, Barclays chief executive, did not apologise, but said: "The misconduct at the core of these investigations is wholly incompatible with Barclays' purpose and values and we deeply regret that it occurred. This demonstrates again the importance of our continuing work to build a values-based culture and strengthen our control environment. We remain completely committed to that effort.
"I share the frustration of shareholders and colleagues that some individuals have once more brought our company and industry into disrepute. Dealing with these issues, including taking the appropriate disciplinary action against the individuals involved, is a necessary and important part of our plan to transform Barclays and remains a key priority."