Normally, taxpayers are not entitled to overpayment interest on refunds, starting from the due date for filing the tax return. However, when a return is filed late, interest doesn't start until the day the return is actually filed. The IRS released a legal memo concerning a foreign corporation that normally would not be required to file a return at all. It filed a return only after it realized that the tax withheld for some dividends it received was excessive. It filed the return only to claim a refund, and filed it late because it didn't realize it was required to file until after the due date. The IRS legal memo concluded that, based on precedents, the return was not "late" until the taxpayer realized the filing obligation. Part 1 explained the holding by the IRS legal memo and the two cases on which it relied. Part 2 raises some questions about the legal analysis and concludes that (a) the conclusions in the IRS memo and the two cases may have been not only difficult to administer but also wrong, and (b) the holding may have very broad application, well beyond the facts in these rulings.