46.5—Conditions to allowance of credit or refund.
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:
(b)
That he has unconditionally repaid the amount claimed to the person who bore the ultimate burden of such amount, or
(c)
That (1) the owner of the article furnished him the amount claimed for payment of the tax, (2) he has filed with the appropriate TTB officer the written consent of such owner to the allowance to the claimant of the credit or refund, and (3) such owner satisfies the requirements of paragraph (a) or (b) of this section.