Incentive Stock Option Alternative Minimum Tax Abatement
From the IRS on the ISO AMT abatement provisions in the Emergency Economic Stabilization Act of 2008:
"The Act provides several changes to help taxpayers with ISO AMT liabilities. First, the Act requires the abatement of any tax liability attributable to the requirement to include amounts in alternative minimum taxable income due to the exercise of the ISO for taxable years ending prior to January 1, 2008, as well as related penalties and interest, to the extent that the liability remains unpaid as of October 3, 2008. Second, the Act accelerates the allowance of the long-term unused minimum tax credit allowing up to 50% of such amount to be a refundable credit for the 2008 and 2009 tax years. Third, the Act allows taxpayers a minimum tax credit for the 2008 and 2009 tax years that is refundable if not otherwise allowable in reducing current tax liability, equal to 50% of the related interest and penalties paid by the taxpayer prior to October 3, 2008, attributable to the exercise of incentive stock options. Thus, provided that an ISO AMT liability has resulted in a long-term unused minimum tax credit, the taxpayer may claim a total credit of 100% of the tax, penalties, and interest paid prior to October 3, 2008, attributable to the exercise of incentive stock options that resulted in those liabilities, over a two-year period."
For more, see here.
"The IRS has identified taxpayers affected by this recent legislation and generally is not collecting on these accounts, pending recalculation of the taxpayers’ liabilities and abatement of appropriate amounts. Taxpayers with ISO AMT liabilities that were unpaid as of October 3, 2008, can expect notification of abatement of the unpaid ISO AMT liability. Taxpayers who believe that they have an unpaid ISO AMT liability, but have not received notification from the IRS regarding this liability by December 31, 2008, should contact the IRS."
Apparently taxpayers who paid the AMT on ISO exercises cannot apply for a refund and are left with the sole (probably completely unsatisfactory) remedy of the acceleration of the long-term unused minimum tax credit.