Tennessee Code Title 67. Taxes and Licenses § 67-3-421

(a) To claim a refund under this part, a person must present to the department a statement that contains a written verification that the claim is made under penalty of perjury and lists the total amount of taxable petroleum products subject to refund. The claim must be filed not more than three (3) years after the date the taxable petroleum products were purchased by the claimant; however, this statute of limitations shall not prevail if a statute of limitations already exists for a particular refund provision. The statement must show that payment for the purchase has been made and the amount of taxes and fees paid on the purchase have been remitted.

(b) The commissioner has the authority to require the claimant to provide adequate documentation to support the claim. The department may make any investigations it considers necessary before refunding the taxes or fees to a person and in any case may investigate a refund after the refund has been issued and within the time frame for making adjustments to tax under this title.