49 CFR § 543.8 - Processing an exemption petition.
(a) NHTSA processes any complete petition. If a manufacturer submits a petition that does not contain all the information required by this part, NHTSA informs the manufacturer of the areas of insufficiency and advises the manufacturer that the agency does not process the petition until it receives the required information.
(b) The agency grants a petition for an exemption from the parts-marking requirements of part 541 either in whole or in part, if it determines that, based upon substantial evidence, the standard equipment antitheft device is likely to be as effective in reducing and deterring motor vehicle theft as compliance with the parts-marking requirements of part 541.
(c) The agency issues its decision either to grant or deny an exemption petition not later than 120 days after the date on which a complete petition is filed.
(d) Any exemption granted under this part applies only to the vehicle line or lines that are the subject of the grant, and are equipped with the antitheft device on which the line's exemption was based.
(e) An exemption granted under this part is effective for the model year beginning after the model year in which NHTSA issue the notice of exemption, unless the notice of exemption specifies a later model year.
(f) If the petition is sought under § 543.6, NHTSA publishes a notice of its decision to grant or deny an exemption petition in the Federal Register and notifies the petitioner in writing of the agency's decision.