The bank's shares have come under such pressure that it emerged last night that the bank's management have begun lobbying the US Securities and Exchange Commission to reinstate the short-selling ban which was in place over the summer to stop traders shorting the shares of about several dozen financial institutions. In addition, Citigroup is also looking for the return of the up-tick ban, which expired in July 2007, which required investors to wait until a company's shares rose before they could short it.