> **Source:** https://knowledge.leegality.com/document-execution/esign-type/aadhaar
> **Site:** Leegality Knowledge Base — https://knowledge.leegality.com
> **About:** Leegality is a document execution platform covering eSigning, stamps, NeSL, workflows, and REST API integration.
> **Navigation:** Every article on this site has a plain-text version at `<article-url>.txt` (this format). To get an index of all articles with their `.txt` links, read: https://knowledge.leegality.com/llms.txt
> **AI Guide:** For instructions on how to navigate this knowledge base as an AI agent, read: https://knowledge.leegality.com/ai-readable.txt

---
# Aadhaar eSign

Aadhaar eSign is a type of electronic signature in India that uses a person's Aadhaar number to verify their identity and sign documents digitally. It is considered legally valid and enforceable in India under the Information Technology Act, 2000.

## Types of Aadhaar eSign

- OTP
- Biometric Thumb
- Iris
- Face

## Use Aadhaar eSign

#### V3 Workflow

During the invite configuration, you need to set the signature type for each invitee by following these steps:

1. In the Invitee card, hover over the **Signature type** dropdown.
2. Toggle ON the **Aadhaar** option.
3. A panel will appear on the right. Choose the Aadhaar eSign method(s) you wish to enable for the invitee. Available options include:
  - OTP
  - Biometric Thumb Scan
  - Iris Scan
  - Face
4. Toggle on **Verify details with Certificate Details** (Optional). Fields to enable are:
  - Verify Name
  - Smart Name Verification
  - Year of Birth
  - Title
  - PIN Code
  - State
  - Gender
  Toggle on the adjacent switch to enable any of the fields listed above.
  **Note:** Enabling a variable automatically makes the verification mandatory for that field.
5. Once selections are made, click **Save** to apply the changes.

#### Workflow Creation

During the invite configuration, you need to set the signature type for each invitee by following these steps:

1. In the Invitee card, hover over the **Signature type** dropdown.
2. Toggle ON the **Aadhaar** option.
3. A panel will appear on the right. Choose the Aadhaar eSign method(s) you wish to enable for the invitee. Available options include:
  - OTP
  - Biometric Thumb Scan
  - Iris Scan
  - Face
  **Note:** At least one eSign method must be enabled by the workflow creator.
4. Toggle on **Verify details with Certificate Details** (Optional). Fields to enable are:
  - Verify Name
  - Smart Name Verification
  - Year of Birth
  - Title
  - PIN Code
  - State
  - Gender
  Toggle on the adjacent switch to enable any of the fields listed above.
  **Note:** Enabling a variable automatically makes the verification mandatory for that field.
5. Once selections are made, click **Save** to apply the changes.

The workflow runner cannot disable this if enabled by the workflow creator, and vice versa.

#### V4 Workflow

To configure Aadhaar eSign for an invitee in a V4 workflow:

1. Expand the **eSign Types** section and enable the **Aadhaar eSign** toggle.
2. Enable the Aadhaar eSign method(s) you want to allow for the invitee:
  - OTP on Phone
  - Biometric Thumb Scan
  - Iris Scan
  - Face Authentication
3. **Set retry attempts** (optional): Enable the **Set retry attempts** toggle, then select the number of attempts from the **Set attempts** dropdown. You can configure a minimum of **0** and a maximum of **10** attempts.

#### Workflow Creation

To configure Aadhaar eSign for an invitee in a V4 workflow:

1. Expand the **eSign Types** section and enable the **Aadhaar eSign** toggle.
2. Enable the Aadhaar eSign method(s) you want to allow for the invitee:
  - OTP on Phone
  - Biometric Thumb Scan
  - Iris Scan
  - Face Authentication
3. **Set retry attempts** (optional): Enable the **Set retry attempts** toggle, then select the number of attempts from the **Set attempts** dropdown. You can configure a minimum of **0** and a maximum of **10** attempts.

> **Info — Note**
>
> If multiple Aadhaar eSign methods are selected, the signer can use any one of the available options to sign the document.

## Signing a Document Using Aadhaar eSign

The signer may receive the invitation to sign the document via Email, SMS, or WhatsApp, based on the sender's configuration.

#### OTP

The Aadhaar eSign **OTP** journey on **Protean** and **CVL** carries your organization's branding. If a **[branding profile](https://knowledge.leegality.com/document-execution/settings/Department/branding)** is configured, your brand logo and colour are applied automatically for a consistent signing experience. If no branding is configured, signers see the default Leegality experience.

1. Click the **Sign** button in the email or use the **Signing Link** received via SMS or WhatsApp.
2. Preview the document and click **Proceed**.
3. Select the Aadhaar eSign method (**OTP on Phone**) and continue.
4. Agree to the consent terms and click **Sign Document**.
5. You will be redirected to eSign Service Provider (ESP) page, such as Protean, CVL, or Verasys.
6. On the ESP page:
  - Enter your **Aadhaar Number/VID**.
  - Select the *I agree to the Terms &amp; Conditions* consent checkbox.
  - Click **Get OTP** to receive an OTP on your registered mobile number.
7. Enter the OTP and click **Verify OTP**.

Once the OTP is verified, the document will be signed successfully.

If the invitee's phone number is linked to their Aadhaar, they can receive the OTP via a phone call. The **Resend via Call** button will appear on the OTP screen 30 seconds after the first code is sent.

#### Biometric Scan

### Prerequisites for Aadhaar Biometric Signing

#### 1. UIDAI-Approved L1 Biometric Device

You must use one of the following **UIDAI-approved L1** devices:

- **Mantra** MFS110 (L1)
- **Startek** FM220U L1
- **Morpho** MSO 1300 E3 L1
- **Precision** PB1000
- **Evolute** Falcon Plus L1

##### What is an L1 Biometric Device?

An **L1 biometric device** is a secure authentication device approved by UIDAI where the capture, encryption, and signing of biometric data happen entirely **inside a tamper-proof hardware environment**.

This is done through a **Trusted Execution Environment (TEE)**, ensuring that:

- Raw biometric data never leaves the device.
- The host OS or applications cannot access unencrypted biometric data.
- Spoofing or unauthorised access is prevented.

This level of security is **mandatory** for all new biometric devices used in the Aadhaar ecosystem.

#### 2. Software Requirements

**For Windows:**

- Install the **Registered Device (RD) services** specific to your biometric device model.

**For Android:**

- Install the **Leegality Helper App**.
- Install the **Registered Device (RD) services** specific to your biometric device model. You can easily find them on Play Store.

On Android, biometric signing requires the **Leegality Helper App** to be installed and the signing link to be opened **from within** that app. If the biometric device is connected but the page still shows *"No device connected"*, check that:

- The **Leegality Helper App** is installed on the device.
- The signing link was opened **inside** the Leegality Helper App, and not directly in a browser or another app.

### Signing a Document Using Aadhaar Biometric

1. Click the **Sign** button in the email or the **Signing Link** received via SMS or WhatsApp.
2. Preview the document and click **Proceed**.
3. Select **Biometric Scan** as the Aadhaar eSign method.
4. Agree to the consent terms and click **Sign Document**.
5. You will be redirected to an eSign Service Provider (ESP) page, such as NSDL (Protean), CDSL, or Verasys.
6. On the ESP page:
  - The system will automatically detect the biometric device.
  - Once detected, enter your **Aadhaar Number/VID**.
  - Check the **Consent** box and click **Capture**.
  - Place your finger on the biometric device and click **OK**.
7. After capturing the fingerprint, a pop-up will confirm the capture with the message *"Fingerprint captured successfully."*
8. Click **OK** to return to the Leegality page with a confirmation message.

#### Face

### Prerequisites for Signing

Aadhaar Face eSign is supported only on Android devices. Ensure the following apps are downloaded and installed from the Google Play Store:

- Leegality Helper
- AadhaarFaceRD

### Signing a Document Using Aadhaar Face

1. Open the **Leegality Helper** app and tap **Continue to Sign Link Upload**.
2. Paste the eSigning link from email, WhatsApp, or SMS, then tap **Proceed to Sign**.
3. Review the document and tap **Proceed**.
4. Select **Face Authentication** as the signing method and tap **Proceed**.
5. Agree to the consent and tap **Sign Document**.
6. You will be redirected to NSDL (Protean) for Aadhaar Face eSign.
7. Tap **OK** to accept NSDL’s Terms and Conditions.
8. Enter your **Aadhaar Number/VID**.
9. Check the consent box and tap **Capture Face Details**.
10. Follow the on-screen instructions and tap **Proceed**.
11. The front camera will open. Blink your eyes for successful capture.
12. Upon successful capture, a pop-up will confirm with "Face captured successfully." Tap **OK** to continue.
13. Tap **Submit**.

You will be redirected back to the Leegality Helper app with a success message: *The document(s) have been signed successfully.*

#### Iris

### Prerequisites for Aadhaar Iris Signing

#### Hardware

You must use one of the following UIDAI-approved iris scanners:

<table>
                <thead>
                    <tr><th>Brand</th><th>Model</th></tr>
                </thead>
                <tbody>
                    <tr><td>iriShield</td><td>MK2120UL</td></tr>
                    <tr><td>Mantra</td><td>MIS100V2</td></tr>
                </tbody>
            </table>

#### Software

<table>
                <thead>
                    <tr><th>Platform</th><th>Setup</th></tr>
                </thead>
                <tbody>
                    <tr>
                        <td><strong>Windows</strong></td>
                        <td>
                            <ol>
                                <li>Install the <strong>Registered Device (RD) services</strong> specific to your iris scanner model.</li>
                                <li>Plug in the device and start the signing process.</li>
                            </ol>
                        </td>
                    </tr>
                    <tr>
                        <td><strong>Android</strong></td>
                        <td>
                            <ol>
                                <li>Install the <strong>Registered Device (RD) services</strong> specific to your iris scanner model from the Play Store.</li>
                                <li>Install the <strong>Leegality Helper App</strong>.</li>
                                <li>Open the signing journey inside the Leegality Helper App.</li>
                            </ol>
                        </td>
                    </tr>
                </tbody>
            </table>

Aadhaar Iris eSign is currently not available on macOS.

### Signing a Document Using Aadhaar Iris

1. Click the **Sign** button in the email or the **Signing Link** received via SMS or WhatsApp. On Android, open the link inside the **Leegality Helper** app.
2. Preview the document and click **Proceed**.
3. Select **Iris Scan** as the Aadhaar eSign method.
4. Agree to the consent terms and click **Sign Document**.
5. You will be redirected to an eSign Service Provider (ESP) page, such as NSDL (Protean), CDSL, or Verasys.
6. On the ESP page:
  - The system will automatically detect the iris scanner.
  - Once detected, enter your **Aadhaar Number/VID**.
  - Check the **Consent** box and click **Capture**.
  - Position your eyes in front of the scanner and follow the on-screen instructions.
7. After capturing the iris, a pop-up will confirm the capture with the message *"Iris captured successfully."*
8. Click **OK** to return to the Leegality page with a confirmation message.

## ESP Errors During Aadhaar Signing

This section lists common errors you may encounter on the eSign Service Provider (ESP) page while signing documents using Aadhaar eSign, along with their causes and solutions.

<table>
  <thead>
    <tr>
      <th>Problem</th>
      <th>Error Message on ESP</th>
      <th>Cause</th>
      <th>Solution</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td rowSpan="2">
        OTP request limit exceeded
      </td>
      <td>
        <strong>NSDL</strong><br/>
        "Failure: You have exceeded Send/Resend OTP Limit. Please try again!"
      </td>
      <td rowSpan="2">
        The signer requested more than three OTPs without submitting any.
        <br/> <br/>A signer can request up to three OTPs. Attempting to request a fourth will result in an error.
      </td>
      <td rowSpan="2">
        Restart the eSign process from Leegality platform. System will automatically route to an available ESP.
      </td>
    </tr>
    <tr>
      <td>
        <strong>CDSL</strong><br/>
        "The eSign Service Provider (ESP) could not complete the eSign request. Message from ESP – OTP Validation Limit Exceeded"
      </td>
    </tr>
    <tr>
      <td>
        Invalid OTP entered repeatedly
      </td>
      <td>
        <strong>On ESP Page:</strong><br/>
        "Invalid OTP! Please enter correct OTP which was received. X attempt(s) remaining for submitting the OTP."
        <br/>
        <strong>After 3 failed attempts (redirected to Leegality):</strong><br/>
        "The eSign Service Provider (ESP) could not complete the eSign request. Message from ESP – Invalid OTP. No Of Retry Attempt Exhausted!!"
      </td>
      <td>
        The signer submitted an incorrect OTP three times consecutively.
        <br/><br/>
        Each signer gets three attempts to enter the correct OTP before the session is terminated.
      </td>
      <td>
        Restart the signing process using the signing link.
      </td>
    </tr>
    <tr>
      <td>
        Expired Virtual ID (VID) used during signing
      </td>
      <td>
        <strong>On ESP Page:</strong><br/>
        "Expired VID is used in input"
      </td>
      <td>
        The 16-digit Virtual ID (VID) entered, or saved in the browser/application, has expired.
        <br/><br/>
        Aadhaar VIDs are temporary and expire after a certain period or when a new VID is generated.
      </td>
      <td>
        Enter a valid VID to proceed, or use the Aadhaar number directly instead.
        <br/><br/>
        To generate a new VID:
        <ol>
          <li>Visit <a href="https://myaadhaar.uidai.gov.in" target="_blank" rel="noopener noreferrer">myaadhaar.uidai.gov.in</a> or open the <strong>mAadhaar</strong> app.</li>
          <li>Go to the <strong>VID Generator</strong> service.</li>
          <li>Log in using the Aadhaar number and the OTP sent to the registered mobile number.</li>
          <li>Select <strong>Generate VID</strong> to receive a new 16-digit VID via SMS.</li>
        </ol>
      </td>
    </tr>
    <tr>
      <td>
        Face authentication failure
      </td>
      <td>
        <strong>On ESP Page:</strong><br/>
        "authentication failed! please contact admin"
      </td>
      <td>
        Intermittent issue with Face authentication on the ESP.
      </td>
      <td>
        Retry after some time. This is typically a transient error and resolves on its own.
      </td>
    </tr>
    <tr>
      <td>
        OTP not received
      </td>
      <td>
        <strong>On ESP Page:</strong><br/>
        "Error in generating OTP request! unable to generate OTP."
      </td>
      <td>
        Intermittent issue on the ESP's end.
      </td>
      <td>
        Close the current session and try again after some time. <br/><br/> If the issue persists, contact <a href="mailto:support@leegality.com">support@leegality.com</a>.
      </td>
    </tr>
    <tr>
      <td>
        Signer's email/mobile not linked to Aadhaar
      </td>
      <td>
        <strong>Message from ESP:</strong><br/>
        "Aadhaar number does not have both email ID and mobile number"
      </td>
      <td>
        The ESP requires at least one contact detail (mobile number or email ID) to be registered with UIDAI/Aadhaar for OTP delivery. This error indicates that the signer does not have the required details linked.
      </td>
      <td>
        Verify and update Aadhaar details before retrying the eSign process.
      </td>
    </tr>
  </tbody>
</table>