27 CFR §24.69

1. (a)Claims. All claims filed under this part for abatement, refund, credit, or remission of tax will be filed on TTB F 5620.8 (2635). Each claim filed under this part will:
   1. (1)Show the name, address, and title of the claimant;
   2. (2)Be signed by the claimant or the duly authorized agent of the claimant; and
   3. (3)Be executed under the penalties of perjury.
2. (b)Supporting documents. Forms, supporting statements, and any other documents required by this part to be submitted with a claim will be attached to the claim and be considered a part of the claim. The appropriate TTB officer may require the submission of additional evidence in support of any claim filed under this part.