Feature allows you to transfer VAT Id of the partner (customer or vendor) to the Intrastat. The following rules of transferring VAT id apply: On vendor side: VAT Id of the vendor postal address, otherwise if empty, primary VAT Id of vendor, otherwise if empty, Tax exempt number from the vendor invoice. On customer side: VAT Id of sales delivery address, otherwise if empty, primary VAT Id of delivery country, otherwise if empty, primary VAT Id of customer, otherwise if empty, Tax exempt number from the sales invoice. In Italy, current logic is not changed: VAT Id from the invoice is transferred, otherwise if empty, Primary VAT Id of customer of vendor is transferred.