> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fincelo.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Digital Signatures

> GST Rule 46 compliant digital signatures on Fincelo tax invoices.

## Overview

Under GST Rule 46, every tax invoice must be authenticated. Fincelo supports digital signatures on all invoices to ensure compliance with GST Rule 46 requirements.

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## What Gets Signed

Every Tax Invoice generated by Fincelo includes:

* Digital signature of the authorised signatory
* Signatory name and designation
* Date and time of signing
* Certificate details

Proforma invoices are **not** digitally signed (they are not tax documents).

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## Setup

1. Obtain a **Digital Signature Certificate (DSC)** from a licensed CA
   * Class 3 DSC required for GST purposes
   * Providers: eMudhra, Sify, (n)Code Solutions
2. Fincelo → **Settings → Compliance → Digital Signature**
3. Upload your DSC (`.pfx` file)
4. Enter the DSC password
5. Set the authorised signatory name and designation
6. All future invoices are signed automatically

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## Validity

DSCs are typically valid for 1–3 years. Fincelo:

* Tracks your DSC expiry date
* Sends a reminder 30 days before expiry
* Blocks invoice generation if DSC has expired (with clear error message)

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## IRN and Digital Signature

When e-invoicing is active:

* The IRN itself serves as authentication for the invoice
* Digital signature provides an additional layer of compliance
* Both appear on the invoice PDF