The increase in profits held outside the U.S. has been particularly large and steady at technology companies, many of which have moved patents and other intellectual property to low- tax locales.
U.S. multinational companies reported earning 43 percent of their 2008 overseas profits in Bermuda, Ireland, Luxembourg, the Netherlands and Switzerland, more than five times the share of workers and investment they have in those jurisdictions, according to a 2013 Congressional Research Service report.
That report cites academic estimates of the annual revenue loss to the U.S. that ranges from $30 billion to $90 billion.
Lawmakers in the U.S., the U.K., France and Italy have scrutinized companies such as Microsoft, Hewlett-Packard Co., Apple, Google Inc. and Amazon.com Inc.
Those inquiries have revealed an Apple subsidiary that earned $30 billion over four years with no home for tax purposes and loans that let HP access its off-limits offshore cash. The Organization for Economic Cooperation and Development and the Group of 20 nations are trying to negotiate a common set of rules to prevent such profit shifting.
Microsoft, Apple
In three years, Microsoft’s profits held offshore have more than doubled and Apple’s have more than quadrupled. Google’s cache has more than doubled in the past three years, to $38.9 billion from $17.5 billion.
The companies and their critics say the growing stockpiles are symbols of a broken U.S. tax system, for which they offer sharply divergent solutions.
Companies including Coca-Cola Co. and United Technologies Corp., working through groups such as the Business Roundtable and the Lift America coalition, advocate adopting a system that would impose lighter taxes on foreign profits.
The U.K. and Japan are reducing their corporate tax rates and making it easier for companies based there to bring money home. Countries such as Ireland -- with a corporate rate of 12.5 percent compared with 35 percent in the U.S. -- are increasingly attractive.