No charges against Madoff's UK operation

No one from the UK arm of Bernard Madoff's fraudulent investment business will face prosecution, the Serious Fraud Office has decided.

In June last year Madoff was convicted of masterminding the world's biggest investment scam, but the SFO decided yesterday there was no evidence that anyone at Madoff Securities International – the London offshoot of Madoff's New York operations – had committed any crimes.

"Following a thorough review of all the available evidence, the SFO has decided to take no action against either the company or its directors, there being insufficient evidence to provide a realistic prospect of conviction," it said in a statement.

Madoff was one of the most powerful men on Wall Street until being unmasked in December 2008 as a fraud. For more than two decades, his firm, Madoff Investment Securities, pretended to invest money from thousands of clients, generating steady returns of about 12 per cent a year. In fact, he was simply using money from new investors to pay clients who cashed out. The $65bn (£41bn) they thought they had in their accounts simply did not exist, and many were ruined.

Madoff is serving a 150-year sentence in a North Carolina jail. Two computer programmers have been charged with assisting him, and his auditor has pleaded guilty to fraud, too. Frank DiPascali, Madoff's right-hand man for decades, is also in jail after pleading guilty to fraud and promising to help investigators prove other people were also in on the scam.

Funds from the New York operation would flow back and forth through the London subsidiary, where staff believed they were investing personal Madoff family money. A lawyer for Stephen Raven, former head of the subsidiary, said that he was "pleased with the outcome of the SFO investigation and that he and his directors have been fully exonerated".

The SFO said it continues to assist the FBI's investigation into the extent of the fraud, and who knew about it. The SFO is also examining whether any UK investment advisers committed crimes when they funnelled money to Madoff.