Last week saw the Financial Services Authority (FSA) react to volatile markets by imposing a ban on the short-selling of financial sector stocks until 16 January, 2009.

Short-selling is a technique whereby investors bet on the price of a stock falling. It involves selling borrowed stock on the assumption that it will be able to be bought back at a cheaper price and returned to the lender. This is one way in which it is possible for investors to profit from falling share prices.