Apple's tax arrangements in Ireland are to come under scrutiny from the European Commission (EC) as the tech giant's financial dealings continue to pose questions.
The EC said that it was investing whether the Irish authorities are providing too favourable a regime to Apple, enabling it to save millions in taxes that could, and should, be paid to the state.
Specifically, the case centres on Apple Sales International and Apple Operations Europe which operate from Ireland. The EC said it would consider whether conditions provided to Apple amounted to state aid.
Commission vice president in charge of competition policy Joaquín Almunia said it was important for the EC to ensure that everyone in the European region was paying their fair share of tax.
"In the current context of tight public budgets, it is particularly important that large multinationals pay their fair share of taxes," he said.
"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 Member State were applied in a fair and non-discriminatory way."
A spokesperson for Ireland's Department of Finance said it would comply with the investigation but insisted it had done nothing wrong.
"Ireland is confident that there is no state aid rule breach in this case and we will defend all aspects vigorously," they said.
"However, we understand that the EC has a responsibility to investigate potential breaches of state aid rules, so we will continue to do everything we can to ensure that they have the full information they require."
Apple said it had not be treated any differently from other firms operating in Ireland.
"We have received no selective treatment from Irish officials. Apple is subject to the same tax laws as scores of other international companies doing business in Ireland," the firm said.
The EC is also investigating Starbucks and car maker Fiat over similar issues with tax regimes in Holland and Luxembourg respectively.
The investigation is not the first time Apple has faced scrutiny over tax arrangements, after US authorities also raised questions over how much tax it pays. Apple has always denied any wrongdoing.
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