Technology giant Apple has been defending itself against accusations that it's avoided paying tax on tens of billions of dollars in profits.
Chief executive Tim Cook told a US Senate committee Apple paid all the taxes it owed, complying with both the law, and the spirit of the law.
He said last year it paid $US6 billion to the US Treasury, a tax rate of about 30%.
On Monday, theSenate Permanent Subcommittee on Investigations said Apple had used "a complex web of offshore entities" to avoid paying billions of dollars in US income taxes. But it said there was no indication the firm had acted illegally.
One country where Apple has a favourable tax regime is the Republic of Ireland.
Committee member John McCain questioned whether Apple had an unfair advantage over smaller companies in the US that don't have the same ability do to locate in Ireland or other countries overseas.
Mr Cook said he believed Apple was one of the largest taxpayers in the US, having paid $6bn in federal corporate income tax in the 2012 fiscal year.
Apple's grilling comes as leading global brands are under growing scrutiny over their tax methods. Google, Amazon and Starbucks have all appeared recently in front of UK politicians to answer questions about their affairs.
