“The Office of Fair Trading (OFT) began an investigation into local bus services yesterday. The regulator said that the inquiry had been prompted by increasing concentration in the sector, which, after a number of takeovers, had left nearly two thirds of services controlled by only five large operators: Arriva, Go-Ahead, Stagecoach, FirstGroup and National Express.”
The Times, 6th March 2009
Source: www.timesonline.co.uk