Customs clearance procedures require prescribed filings, assessment, and examination under both manual and EDI systems. Import clearance requires filing a Bill of Entry or electronic cargo declaration, classification and valuation by appraising groups, possible physical examination or sampling, and payment of assessed duty before release; EDI processing automates calculations, generates acknowledgements, and accepts system appraisal in specified cases. Warehousing, bonds, amendments, and advance entry are specially regulated. Export clearance requires PAN based registration, filing of a Shipping Bill or electronic declaration, export appraiser verification, shed examination and a let export order; drawback claims and manifests are processed through EDI.