26 U.S. Code § 6514 - Credits or refunds after period of limitation
If made after the expiration of the period of limitation for filing claim therefor, unless within such period claim was filed; or
In the case of a claim filed within the proper time and disallowed by the Secretary, if the credit or refund was made after the expiration of the period of limitation for filing suit, unless within such period suit was begun by the taxpayer.
Any credit against a liability in respect of any taxable year shall be void if any payment in respect of such liability would be considered an overpayment under section 6401(a).
Written determinations for this section
These documents, sometimes referred to as "Private Letter Rulings", are taken from the IRS Written Determinations page; the IRS also publishes a fuller explanation of what they are and what they mean. The collection is updated (at our end) daily. It appears that the IRS updates their listing every Friday.
Note that the IRS often titles documents in a very plain-vanilla, duplicative way. Do not assume that identically-titled documents are the same, or that a later document supersedes another with the same title. That is unlikely to be the case.
Release dates appear exactly as we get them from the IRS. Some are clearly wrong, but we have made no attempt to correct them, as we have no way guess correctly in all cases, and do not wish to add to the confusion.
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