Procurement certificate verification and re-warehousing requirement enforce duty-exemption compliance and may trigger recovery actions. Verification of duty-exemption documentation under the EOU scheme requires authentication of Procurement Certificates and timely receipt of Re-warehousing Certificates. Random checks of PCs will be conducted and verification is compulsory for first-time importers; hand-delivered PCs/RWCs must arrive in sealed covers and may be cross-checked against registered-post copies. Duty-exemption completion depends on RWCs within prescribed timelines; persistent pendency will trigger demand notices, suspension of duty-free clearance, or requirement of bank guarantees. Commissioners must furnish specimen signatures of issuing authorities.