But if the business is a corporation the tax rules are more complex.

FORBES: Selling Your Business? Taxes Are Key

All the companies under fire over the amount of corporation tax paid said that they operated within the tax rules and regulations and have done nothing wrong.

BBC: Vince Cable attacks corporate 'tax abuse'

But it rules out devolving corporation tax unless it is also devolved to Scotland and Northern Ireland, national insurance, capital gains tax, VAT and fuel duty.

BBC: Commission calls for Welsh government income tax powers