VAT gaps can generally be found in countries that collect indirect taxes. This hiatus has led many tax administrations to implement Continuous Transaction Controls (CTCs), through which transactional and accounting data are monitored in real-time or near real-time. However, even countries with sophisticated CTCs may encounter fraud involving missing traders and non-existent supplies. This creates holes in the VAT collection chain leading to significant shortfalls. Although taxpayers are used to validating incoming e-invoices and e-signatures, many governments have introduced additional validation requirements to tackle the loss of revenue.