The top financial firms have been actively taking steps to prevent rogue brokers from gaming their systems. But there will always be rogues, it seems.

The latest: An oil trader at PVM Oil Associates, the world's largest OTC oil brokerage, said a rogue had placed a massive bet in the Brent oil market that resulted in a loss of $10 million for the firm. The big bets accounted for a huge spike in prices last week. Prices rose in one hour from $71 to $73.5, the highest level for the year.

The London-based company was forced to close out the unauthorized trades at big losses, reports the Financial Times. This incident follows one involving a Morgan Stanley trader was reported to have placed large, unauthorized trades while under the influence of alcohol. 

For more:
- here's the FT article

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