Citigroup lost $50 million to "fat finger" trader - The WSJ

Citigroup lost $50 million because of a trader with a "fat finger," - The WSJ

Citigroup's London-based remote trader mistakenly added an extra zero to the total on the morning of May 2. The consequence was a collapse in European stocks - after a 5-minute sell-off in the OMX Stockholm 30 index, the shake-up took place on exchanges from Paris to Warsaw, with a total loss of $322 billion.

The trader with the "fat finger" was sent on leave pending the outcome of the investigation. So far, the conclusions are that the remote transaction had nothing to do with the error, the usual human factor worked.

Citigroup's internal algorithms automatically break large deals into parts, and partially erroneous deals were stopped, but the losses were still significant - the bank lost more than $50 million.