The big four audit firms in the UK face a Competition Commission investigation after the Office of Fair Trading said there were "reasonable grounds for suspecting that there are features of the market that restrict, distort or prevent competition".
Clive Maxwell, executive director of the OFT, said: "We have been concerned for some time about the extent of competition in this market, with only four large players and substantial barriers to entry and switching." The OFT said it will talk to regulators, government, business and the audit industry on whether to refer the market to the commission over the next few weeks with a statutory consulation later in the year.
The big four accountants – KPMG, Ernst & Young, Deloitte and PricewaterhouseCoopers – last year audited 99 firms in the FTSE 100 index. According to a parliamentary report in March, blue-chip companies change auditors only every 48 years on average.