Unsigned GST notices and assessment orders are invalid when authentication is absent; curative provisions cannot save the defect.

GST orders and show cause notices must be authenticated by the issuing authority through a digital signature or other prescribed mode under Rule 26(3) of the CGST Rules, 2017; an unsigned communication is no order in law. Sections 160 and 169 of the CGST Act, 2017 do not cure the defect because the problem is absence of authentication, not a mere mistake, omission, or issue of service. Following prior High Court authority, the unsigned notice and assessment order were held unsustainable and were set aside in favour of the assessee.

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Issues: Whether a show cause notice and assessment order issued under the GST regime without the issuing authority's signature, digital or physical, are sustainable in law.

Analysis: Rule 26(3) of the Central Goods and Services Tax Rules, 2017 requires authentication of orders by a digital signature or other prescribed mode. An unsigned order was treated as no order in the eye of law. Sections 160 and 169 of the Central Goods and Services Tax Act, 2017 were held inapplicable to cure the defect, as the issue was not a mere mistake, omission, or mode of service, but absence of authentication itself. The Court followed prior coordinate and other High Court decisions taking the same view.

Conclusion: The unsigned show cause notice and impugned order were held unsustainable and were set aside, in favour of the assessee.

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