British Steel was a major British steel producer. It originated from the nationalised British Steel Corporation (BSC), formed in 1967, which was privatised as a public limited company, British Steel plc, in 1988. It was once a constituent of the FTSE 100 Index. The company merged with Koninklijke Hoogovens to form Corus Group in 1999.

The Financial Times Stock Exchange 100 Index, also called the FTSE 100 Index, FTSE 100, FTSE, or, informally, the "Footsie", is the United Kingdom's best-known stock market index of the 100 most highly capitalised blue chip companies listed on the London Stock Exchange. Founded in 1984 by the Stock Exchange to better reflect activity on the market, it replaced the Financial Times own FT 30.