The Financial Services Authority (FSA) has fined Swift Trade £8m for market abuse, a decision the now-dissolved Canadian firm is appealing.
"In the FSA's opinion, between 1 January 2007 and 4 January 2008, Swift Trade's manipulative trading caused a succession of small price movements in a wide range of individual shares on the London Stock Exchange from which Swift Trade made substantial profits," the FSA said in a statement.
"It has not been possible to measure Swift Trade's profits precisely; however, they were in excess of £1.75m," the FSA added.
Swift Trade has lodged an appeal with the Upper Tribunal, which has powers to uphold, vary or cancel the FSA fine.
As part of its "credible deterrence" crackdown on market abuse, the FSA decided to publish in May this year its decision in principle to fine Swift Trade.
This was only the second time the FSA used newly acquired powers to publish a decision before any appeal runs its course.
City A.M. Reporter