German banking regulator BaFin is imposing further fines of €13.0 million ($13.9 million) on major US-based bank Citigroup due to a serious mishap in share sales, the regulator announced on Thursday.
In May 2022, a trader at the bank had briefly triggered turbulence on several stock exchanges with a false entry in the bank's system.
According to earlier information from the UK Financial Conduct Authority (FCA), the man actually wanted to sell securities worth $58 million, but actually put a block of shares worth $444 billion up for sale.
The bank's control systems prevented some of the unwanted sales, but not all of them. In the end, shares worth around $1.4 billion were sold on European stock exchanges before the trader cancelled the order.
The mistake triggered a five-minute sell-off on the OMX Stockholm 30 stock index and caused chaos on exchanges from Paris to Warsaw.
The Frankfurt-based subsidiary Citigroup Global Markets Europe AG has outsourced the monitoring and administration of computer trading to London, where the costly error occurred.
However, according to BaFin, the Citigroup subsidiary is still responsible for the appropriate design of the trading system. The system failed to "prevent the sending of erroneous orders that may create or contribute to a disorderly market."
The system failed to recognize the trader's input error and transmitted incorrect orders, the regulator found.
The regulator, which announced the fine on Thursday, said it was the largest ever given to a bank in Germany over a consumer protection issue.
In May, the British Financial Conduct Authority (FCA) and the Financial Services Authority (PRA) had ordered Citigroup to pay a total of over £61.6 million (about $78.2 million).
