Group 1 - Export goods and services that occurred before the export tax refund (exemption) registration can still apply for tax refunds after the registration is completed [3] - Export enterprises must withdraw their export tax refund (exemption) registration before canceling tax registration [3] - Electronic sales contracts signed with foreign merchants are compliant with the registration document requirements [4] Group 2 - The retention period for export tax refund (exemption) registration documents is five years [4]