The Signed QR Code can be verified by anyone using the offline app provided on the IRP portal. Content of the signed QR code can be easily verified by the taxpayers or Tax Officials to ascertain whether the invoice is registered with the IRP and is digitally signed by the IRP itself. By validating the QR code data content with the digitally signed content (which is part of the QR code itself), one can check the authenticity of the document contents. Suppose the content of the QR code is tampered with. In that case, the signature verification fails, and the e-Invoice will become invalid.