The European Commission has opened an in-depth investigation into Apple's corporate tax affairs on suspicion that the company did not pay its fair share of income taxes. "It cannot be accepted that large companies do not pay their fair share in taxes," Joaquín Almunia, Commission Vice President in charge of competition policy, said Wednesday. Under the EU's state aid rules, national authorities cannot take measures allowing certain companies to pay less tax than they should if the tax rules of the EU member state were applied in a fair and non-discriminatory way, he said.