What Is E Sign And How E Sign API Works?

Introduction

What is E Sign?

Have you ever stuck in the situation like, you have to sign a very important document urgently but because of some reasons document is not available physically at your place? That’s where “E-Signatures” comes for your help! You can sign from anywhere any time if you use e-signatures. There are certain types of e-signatures which you can use to sign your documents which are most secured and accepted all over India.

Types of eSignatures

Digital Signatures certificates:

It is a digital certificate issued by a licensed Certifying Authorities (CA’s) of India. Digital Signature Certificates issued by Certifying Authorities are divided in classes according to their uses. We required Class 3 Individual or Organization sign Digital Signature Certificate to sign documents. These digital Signature Certificate comes with highly secured cryptographic USB Token like Hyp2003, WD proxkey etc. You can read our other blog where we have explained in detail about signing PDF Documents with Digital signature USB Token.

Biometric/Aadhar Based E-Signatures:

A licensed Certifying Authorities can generate e-signature of any person who have Aadhar card in INDIA using his/her data stored in UIDAI(Unique Identification Authority of India). We can generate Aadhar E-Sign by using trusted biometric devices or by OTP process. If we use biometric method user should have trusted biometric devices like Mantra, Morpho, Startek etc. Or user can generate a OTP to his registered mobile number/Email ID to generate Aadhar esign. It is most trusted & secured way to generate esign, because here esign is generating directly using UIDAI data. Hence, it is accepted all over INDIA.

Simple Electronic Signatures:

It includes simple scanned images of your handwritten signatures. You can easily scan and save image of your handwritten signature and apply it any document online. You can visit our website signsecure.in if you don’t have any facility to add your handwritten signature on your documents. There are various options which you can use to sign your documents.

Importance of eSignatures

• Ease in Signing: We can sign any document from anywhere with extremely ease using E-Signatures.
• Sharing/Storing Documents: We can easily share or store any document online without downloading it for signing manually.
• Complete Paperless: Now days it is very big task to store all important documents. We can easily store our documents online and authenticate it with e-signatures to save trees & go paperless.
• Time Saver: It might take couple of hours to sign bulk documents with old fashion handwritten signature but with e-sign you can sign lakhs of documents in a minute.
• Most Secured & trusted: E-Signatures are most secured & trusted all over India because it are generated by government authorities like AUDAI & licensed Certifying authorities.

Legal Recognition

Electronic signatures are legally recognized in India and are provided for in the Information Technology Act, 2000 (“ITA”), the Indian Contract Act of 1872 (“ICA”) and the Electronic Signature or Electronic Authentication Technique and Procedure Rules, 2015 (“ESEATPR”). Also trusted in USA with laws like ESIGN Act and eIDAS in the EU.

What is E Sign API or Digital Signature API?

IT is an application programming interface that enables electronic signing of documents using a legally valid Digital Signature Certificate (DSC) or Aadhar E Sign, without the need for physical tokens or manual signature processes.

In simple terms, these API allows you to digitally sign a document online using your Aadhaar based authentication or other digital signature methods—without downloading, printing, or scanning.

How E Sign API Works?

An eSign API allows businesses and developers to integrate electronic signing functionality directly into their websites, mobile apps, or internal systems. This enables users to sign documents digitally without leaving the platform, creating a seamless and efficient user experience. Here’s how it typically works:

1. User Initiation

The process begins when a user uploads or accesses a document that needs to be signed. This can be triggered from a web portal, a CRM, ERP, or any digital platform.

2. Authentication

Before the signing process, the API validates the signer’s identity. This can be done through:

• Aadhaar OTP: An OTP is sent to the user’s Aadhaar-linked mobile number.
• Biometric Verification: User provides fingerprint or iris data using a trusted biometric device.
• Digital Signature Token (USB Token): For Class 3 DSC-based signing.

3. Document Preparation

The document is processed and temporarily stored in a secure environment. The API places a signature field at the appropriate location(s) in the document.

4. Signing the Document

Once authenticated, the user approves the signature. The API uses Public Key Infrastructure (PKI) to digitally sign the document. This ensures:

• The signature is encrypted.
• The document cannot be tampered with after signing.

5. Signature Certificate Attachment

After signing, a digital signature certificate with signer details (name, date, time, and IP address) is embedded into the document. This adds legal validity and traceability.

6. Delivery and Storage

The signed document is returned to the application or sent to desired parties. It can also be stored securely in a cloud or local server.

Why Use E Sign or Digital Signature API?

• Automation: Perfect for businesses that need bulk document signing (e.g., invoices, contracts, HR letters).
• Customization: You can tailor the signing workflow to your app's look and feel.
• Speed & Scalability: Handle thousands of signatures per minute without manual intervention.
• Compliance: Most APIs comply with Indian laws (like IT Act 2000) and global standards (like eIDAS and ESIGN Act).

Real-World Example

✅ 1. Human Resources (HR)

Use Case: On boarding & Employee Documentation
How It Works: HR teams integrate Digital Signature API into their HRMS/HRIS to enable digital signing of:

• Offer letters
• Appointment letters
• NDAs
• Policy acknowledgements
  Benefits: Saves time, ensures compliance, and speeds up on boarding—especially for remote hiring.

✅ 2. Banking & Financial Services

Use Case: Digital Loan Applications & Account Opening
How It Works: Banks integrate Aadhaar eSign API to enable:

• e-KYC
• Loan agreements
• Consent forms

Account opening forms
Benefits: Faster customer on boarding, less paperwork and improved fraud control.

✅ 3. Insurance Sector

Use Case: Policy Issuance & Claims
How It Works: Insurance companies use e signature APIs to allow customers to:

• Sign policy documents
• Submit claim forms
• Approve terms and endorsements
  Benefits: Speeds up policy delivery, enhances customer convenience, and reduces operational costs.

✅ 4. Education Sector

Use Case: Document Management for Students & Staff
How It Works: Schools, colleges, and universities use Digital Signing API for:

• Issuing digital mark sheets
• Transcripts and certificates
• Staff contracts and approvals
  Benefits: Enables digital campus operations and reduces administrative workload.

✅ 5. Government Services & e-Governance

Use Case: Public Document Signing
How It Works: Government portals like ICEGATE, GSTN, and UIDAI use Aadhaar and DSC based eSign APIs for:

• E-filing returns
• Customs clearance
• License & permit applications
  Benefits: Increases transparency, eliminates in-person visits, and speeds up service delivery.

✅ 6. Legal & Compliance

Use Case: Contract & Agreement Signing
How It Works: Legal teams integrate Aadhar e sign API & Digital Signature API to manage:

• Client agreements
• Vendor contracts

Arbitration documents
Benefits: Enables secure, tamper-proof, and court-admissible e-signatures

✅ 7. Logistics & Supply Chain

Use Case: Digital Proof of Delivery (e-POD)
How It Works: Delivery personnel or warehouse teams use mobile apps integrated with Document Signing API to:

• Sign delivery receipts
• Confirm dispatch and receipt of goods
  Benefits: Real-time tracking and reduced paperwork.

✅ 8. Healthcare

Use Case: Patient Consent Forms & Medical Records
How It Works: Hospitals and clinics use eSignature APIs to obtain digital consent for:

• Surgeries and treatments
• Insurance claims
• Sharing medical data with specialists
  Benefits: Ensures privacy, legal compliance, and speeds up patient on boarding.

Conclusion

In today's digital world E Sign & Digital Signature have become essential tool for all businesses, government organizations and individuals like us. It simplifies the online document signing process with highest level of security. E Sign API & Digital Signature API provides reliable solution to across industries with ability of integrating seamlessly with any existing system which allows organisations to go paperless with ease.