19 CFR §181.113

1. (a)Request; form and filing. The exporter or producer of the merchandise which is the subject of an adverse marking decision may request a statement concerning the basis for the decision by filing a typewritten request, in English, with CBP, either at the port of entry or electronically. The request should be on letterhead paper in the form of a letter and clearly designated as a “Request for Basis of Adverse Marking Decision” and shall be signed by the exporter, producer or his authorized agent. The provisions of § 174.3 of this chapter shall apply for purposes of signature by a person other than the principal.
2. (b)Content. The Request for Basis of Adverse Marking Decision letter shall set forth the following information:
   1. (1)The name and address of the exporter or producer of the merchandise and the name and address of any authorized agent filing the request on behalf of such principal;
   2. (2)A statement that the inquirer is the exporter or producer of the merchandise that was the subject of the adverse marking decision;
   3. (3)In the case of a Canadian exporter or producer, the employer number assigned by Revenue Canada, Customs and Excise; in the case of a Mexican exporter or producer, the Federal taxpayer registry number (RFC); and the Customs identification number of an authorized agent filing the request on behalf of such principal;
   4. (4)The number and date of each entry involved in the request;
   5. (5)A specific description of the merchandise which is the subject of the adverse marking decision; and
   6. (6)A complete statement of all relevant facts relating to the adverse marking decision and the transaction to which it relates, including the date of the decision.