The New York Times reports that the SEC has launched a large-scale trawl for insider trading on the New York markets. Reportedly, mutual fund managers have been complaining that their brokers are conspiring with hedge funds to front-run their deals. The novelty is that the SEC isn't looking at one suspicious trade: it's pulled in all trading data for the stock and derivatives markets for the two weeks before the end of quarter in September last year. This will be a massive data mining exercise, but it's more likely to catch more exotic insider trades - the credit derivatives market in particular has come under scrutiny in the past.
In Britain, the FSA started to look at this last year.