An increasing number of U.S. nationals are giving up their citizenship, causing confusion due to a discrepancy in official records of national agencies.

While the FBI says 3,000 U.S. citizens turned in their passports in the last quarter of 2012, bringing the year’s tally to 4,385, the IRS pegs it at 45, reports The Isaac Brock Society, a forum that comprises individuals concerned about the treatment by the U. S. government of U.S. persons living in Canada and abroad.

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One reasons for this discrepancy is believed to be the fact that FBI records only include those U.S. people who lose their citizenship by way of renunciation.

The report says the FBI numbers don’t include the number of people who relinquished citizenship or gave up long-held green cards, acts that should result in one’s name appearing in the Federal Register, which tracks Americans who renounce their citizenship.

Based on the technical differences in their definition, relinquishment preferable to renunciation as the former is considered in a more positive light and isn’t confused with an expatriation to avoid taxes. Relinquishment doesn’t require also saves U.S. citizens the $450 fee they’d have to pay if they chose renunciation of their citizenship.

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Some may look at low IRS numbers as an indication that, for tax purposes, the agency may still be keeping close tabs on thousands of former U.S. citizens settled abroad.

According to a Yahoo! Finance report, financial and cultural considerations have driven many U.S. people, including celebrities such as Facebook co-founder Eduardo Saverin, singer Denise Rich and actor Jet Li, to relinquish their U.S. citizenship and relocate to countries defined as ‘tax havens,’ including Switzerland, Bahamas and Singapore.

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