The US Senate has criticised Microsoft and Hewlett-Packard for their use of tax avoidance schemes, which it says is rampant in the tech sector.
The Senate's Permanent Subcommittee on Investigations said the companies used places such as the Cayman Islands so they did not have to pay US taxes.
The chairman of the panel said their practices ranged from "egregious to dubious validity".
Carl Levin has been investigating offshore tax havens for years.
He said the industry was probably the number one user of these offshore entities to transfer intellectual property.
The committee said that between 2009 and 2011, Microsoft moved $21bn (£13bn) offshore, almost half its US retail sales revenue.
The panel said the moved saved it up to $4.5bn in taxes on goods sold within the US.
It also said the company moves royalty revenue to divisions in lower-tax nations, including Singapore and the Republic of Ireland.
The panel said Hewlett-Packard funded US operations with inter-company loans, using an exception in the law for short-term loans, to avoid billions of dollars in taxes.
Where your tax dollars cyber-went
Where your tax dollars cyber-went
“If you trust in yourself, and believe in your dreams, and follow your star. . . you'll still get beaten by people who spent their time working hard and learning things and weren't so lazy.”
Re: Where your tax dollars cyber-went
There's an easy solution to this, and that is to require corporations to pay tax on the income earned by any overseas corporation in proportion to their ownership share. Which would treat corporations exactly the same as individuals who are taxed on their worldwide income. After all, corporations are people, right Mitt?
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