Apple has also been cash tax efficient since it has paid 13% in cash vs. a reported 25%. eBay has the lowest reported tax rate at 17% and the closest difference between its cash tax rate to its reported.

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They ignore the fact that there is a difference between your marginal tax rate and your effective tax rate.

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The difference can be between a 50% tax rate and a 25%-28% tax rate, depending on the state, says Greg Brogger, cofounder and president of SharesPost.

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That could be the difference between a 20% or 30% tax rate for capital gains and dividends.

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Under current tax law, in order to bring the foreign-held cash back into the U.S., they would have to pay the difference between the U.S. corporate tax rate and the taxes already paid in local jurisdictions.

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The cost of a deemed dividend is also greater today because the difference between the current U.S. tax rate (the highest of any industrialized country) and the average tax rate on earnings of foreign subsidiaries is substantially greater than in 1976.

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Democrats, however, have proposed plugging tax loopholes as a means of making up the difference in revenue if the corporate rate is lowered.

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While U.S. companies get a credit for the taxes they pay overseas, they are still liable for the difference between what they pay abroad and the higher U.S. marginal tax rate.

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Donald Marron, director of the Tax Policy Center, thinks that this is precisely why cutting taxes no longer does the job, telling David Leonhardt of the New York Times that when the top marginal rate was 70 percent of higher, as it was from 1940 to 1980, tax cuts could make a big difference.

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