But insiders at the FCA claim that their case teams, which draw on 3,000 people, need time in order to accumulate the right evidence to convict those who breach City and criminal laws. There are currently no time limits for the FCA to charge people after they have been arrested.
However, those at the regulator point to the success of their criminal cases, highlighting that 80 percent of cases prosecuted conclude in a criminal conviction.
Seven men have been charged in relation to Operation Tabernula, including Martyn Dodgson, a senior corporate broker at Deutsche Bank and Graeme Shelley, a broker at Novum Securities. Last year, Paul Milsom, a senior trader at Legal & General, pleaded guilty to passing on confidential details about 14 companies to Shelley. The 12-year veteran of Legal & General is said to have made £161,588 ($265,776) from his trades and £80,776 for trades via a second broker. He was jailed for two years and ordered to repay £245,657.
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According to evidence uncovered by Operation Tabernula, Milsom shared price-sensitive information using an unregistered mobile phone moments before Legal & General made large block trades, an illegal form of trading known as "front running".
However, the FCA has also foundered in cases that have been proven to be wrong. One of the regulators most recent investigations was dropped without charge but resulted in the closure of Lodestone hedge fund.
Carl Linderum and Tim Whyte, the founders of Lodestone were arrested in February 2013 along with Carl Esprey a fund manager at GLG, owned by the world's largest listed hedge fund Man Group. The nine-month investigation was dropped in November but much of the damage had already been done. Lodestone Investment Partners was forced to close and staff laid off as its investors reacted to press speculation about the arrests of its founders.