Electronically authenticated GST show-cause notices,...

Electronically authenticated GST show-cause notices, adjudication orders and DRC summaries uploaded on the common portal remain valid even where taxpayer-facing PDFs display no physical or digital signature. Registered digital signature certificates, immutable electronic records, hash values and officer-certificate mapping satisfy electronic-authentication requirements; form signature fields cannot add to the Rules. Portal uploads constitute valid service and begin limitation; after the portal expressly identified the Additional Notices and Orders tab, taxpayers cannot claim ignorance of communications uploaded there, while challenges concerning earlier uploads remain open. GST communications may bear either a DIN or an independently verifiable RFN, but communications bearing neither identifier are invalid. Conflicting coordinate-bench views require reference to a larger bench rather than a contrary departure.