FSA seeks to stop 'back-door' listings in London The FSA also tightened its grip on so-called "externally managed companies" - companies which outsource senior management roles to offshore advisors - to ensure that such companies would not be eligible for a primary London Stock Exchange listing. David Lawton, the FSA's acting director of markets, said: "It is important that the listing rules continue to keep pace with market developments and the needs of investors. We believe that this consultation, which proposes specific changes, but also invites debate about the corporate governance standards that should underpin the premium listing standard, will serve that purpose and welcome responses to help us maintain an appropriate regime for the UK. The FSA's move follows a similar step to increase investor protection taken in December by the FTSE Group, which runs the blue-chip FTSE 100 index. At the time, the FTSE Group said it was tightening rules governing entry to its indices in order to protect minority investors and stop companies with poor corporate governance from exploiting loopholes to secure a spot on London's prestigious stock market. FTSE said companies which want to be included in its UK indices - including the FTSE 100 - must ensure at least 25pc of their shares are freely tradeable. Several foreign-owned natural resources companies whose shares are listed in London have the majority of their shareholding controlled by two or three powerful individuals. Increasing the free float of such companies would allow smaller investors a greater say in the running of such companies.