27 C.F.R. § 46.5
No credit or refund to which this subpart is applicable shall be allowed or made, pursuant to a court decision or otherwise, of any amount paid or collected as a tax unless a claim therefor has been filed, as provided in this subpart, by the person who paid the tax and the claimant, in addition to establishing that he is otherwise legally entitled to credit or refund of the amount claimed, establishes:
[T.D. 6395, 24 FR 599, Jan. 28, 1959. Redesignated at 40 FR 16835, Apr. 15, 1975, as amended by T.D. ATF-472, 67 FR 8880, Feb. 27, 2002]