IRS tightens offshore tax loophole.

• Position: New report

According to the IRS, its Offshore Voluntary Disclosure programs have brought in more than $5 billion in back taxes, interest and penalties--and it will tighten the eligibility requirements. The IRS has closed a loophole that's been used by some taxpayers with offshore accounts. Under existing law, if a taxpayer challenges in a foreign court the disclosure of tax information by that government, the taxpayer is required to notify the U.S. Justice Department of the appeal.

If the taxpayer fails, to...