The London Stock Exchange is a stock exchange located in the City of London, England, within the United Kingdom. As of December 2010, the Exchange had a market capitalization of US$3.6 trillion, making it the fourth-largest stock exchange in the world by this measurement (and the largest in Europe). The Exchange was founded in 1801 and its current premises are situated in Paternoster Square close to St Paul's Cathedral in the City of London. The Exchange is part of the London Stock Exchange Group.
The London Stock Exchange Group plc is the leading diversified stock exchange group in Europe. It owns the Borsa Italiana and London Stock Exchanges. It is a member of the FTSE 250 Index as of 21 June 2010.