These plc companies used to be referred to as blue chip companies. They are the largest in terms of market capitalisation (share price multiplied by number of shares issued). Although these plc companies are quoted on the LSE, the CEOs are not all based in the UK. Some companies are so large that they have both CEO and several MD positions.
Chief executives & managing directors in the top 350 companies quoted on the London Stock Exchange - 310 postal addresses, phone numbers & email addresses