A GSTN advisory dated 19 September 2026 makes emSigner version 3.3 mandatory on the GST portal for DSC tokens issued on or after 21 September 2026. The change follows the Controller of Certifying Authorities (CCA) move to FIPS 140-3: certifying authorities had to stop issuing DSCs on older FIPS 140-2 tokens by 21 September 2026.
Who is affected
- Anyone who signs GST filings with a DSC that was issued or renewed on a new token from 21 September 2026.
- Directors and signatories renewing a DSC. A DSC downloaded to a FIPS 140-2 token by 21 September 2026 stays valid until it expires, but that token cannot be used for a renewal or fresh download. CCA allows one exception: a free, one-time reissue of an active DSC for its remaining validity.
If your current DSC and token still work, nothing changes. emSigner 3.3 also works with older tokens, so upgrade if signing fails.
What to do
- Budget for a FIPS 140-3 token at your next DSC renewal.
- If you have a token issued from 21 September 2026, install emSigner 3.3 from the GST portal’s DSC help page. It needs a 64-bit system and Java 1.8; Java 9 and above are not supported.
- This advisory covers the GST portal only. If MCA or income tax signing fails, check that portal’s own signer download.
More on DSCs for company filings: our DSC guide for MCA filings.
Sources: GSTN advisory of 19 September 2026 (ICAI mirror), Taxguru.
