19 C.F.R. § 181.75
(a) General. Except in the case of a pattern of conduct within the meaning of § 181.76(c) of this part, following receipt and analysis of the results of an origin verification initiated under § 181.72(a) of this part in regard to a good imported into the United States and prior to denying preferential tariff treatment on the import transaction which gave rise to the origin verification, Customs shall provide the exporter or producer whose good is the subject of the verification with a written determination of whether the good qualifies as an originating good. Subject to paragraph (b) of this section, the written origin determination shall be sent within 60 calendar days after conclusion of the origin verification process, unless circumstances require additional time, and shall set forth:
(b) Negative origin determinations. If Customs determines, as a result of an origin verification initiated under § 181.72(a) of this part, that the good which is the subject of the verification does not qualify as an originating good, the written determination required under paragraph (a) of this section:
(2) Shall, in addition to the information specified in paragraph (a) of this section, set forth the following:
(iv) A statement advising the exporter or producer of the right to file a protest under 19 U.S.C. 1514 and part 174 of this chapter: