This document amends the Customs Regulations regarding the filing of certain inventory reports by bonded warehouse proprietors. Instead of requiring that these reports be filed with Customs, the document requires that bonded warehouse proprietors maintain these inventory reports after their preparation. In some instances when the inventory report is prepared, a letter must be submitted to Customs certifying that the report has been prepared. As amended, the port director is the Customs officer to whom certification letters must be submitted and to whom the annual report covering smelting or refining operations must be submitted. These changes and other changes made by this document are intended to simplify inventory recordkeeping procedures for warehouse proprietors. The changes are consistent with Customs' movement toward a post-audit environment and the spirit of ``shared responsibility'' embodied in the Customs Modernization provisions of the North American Free Trade Agreement Implementation Act.