27 CFR § 70.121
Amounts treated as overpayments
April 24, 2020
(a) The term overpayment includes any payment of any internal revenue tax which is assessed or collected after the expiration of the period of limitation applicable thereto.
(b) An amount paid as tax shall not be considered not to constitute an overpayment solely by reason of the fact that there was no tax liability in respect of which such amount was paid.
[T.D. ATF-251, 52 FR 19314, May 22, 1987. Redesignated by T.D. ATF-301, 55 FR 47606, Nov. 14, 1990]