In this article in Accounting Today by Michael Cohn, Mitt Romney has said he has been audited in the past and implied his tax preparer did a good job, so I assume he didn’t owe any additional taxes:
http://www.accountingtoday.com/news/irs-audited-mitt-romney-63452-1.html?ET=webcpa:e3774:204199a:&st=email
One point Romney made in the article was that he paid what was legally due, so he is following the most important tax planning strategy – don’t pay the government anymore taxes than you are required to.
Call me or email me if you want to discuss this or think you pay too much tax.
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email bstonercpa@sbcglobal.net phone 818-317-6035