What Are Digital Signature Certificates? 

A Digital Signature Certificate or DSC is a cryptographically secure key issued by certifying authorities (CAs) to validate and confirm the identity of the person who holds the certificate.

DSCs are typically issued and utilized when businesses need to digitally sign documents online and require a means to securely authenticate the signature and validate the signed document.

Applicants can also receive DSCs when using Aadhaar eKYC-based authentication, wherever offered by the certifying authorities.

In addition to these methods, a letter containing the information of the online signature certificate applicant issued by a bank, as retained in the bank’s database can be used. Such certificates should be certified by the bank manager.

Here’s a short summary of what businesses need to know about DSCs:

  • They certify a digitally signed document
  • They contain the details of the subscriber (name, etc.,) that help with their identification
  • They can identify the certifying authority using them
  • They are electronically signed by the Certifying Authority using them
  • They contain the public key of the subscriber
  • They are typically valid for 1-2 years

Why Is a Digital Signature Certificate Required?

Just like how there are physical documents for manual signatures, a DSC or Digital Signature Certificate facilitates signatures made on e-forms and online documents.

The certificate authenticates the identity of the signer digitally. Along with these facilities, a DSC offers a high level of security for online transactions by ensuring the privacy of the information present on the eSigned document.

Users can use a digital signature certificate to encrypt data so that only the intended recipient can have access to it. Also, an eSignature certificate ensures that the document has not been changed in transit and verifies the identity of the user as the sender of the message.

Digital Signature Certificate Types

Certifying authorities can issue three different types of DSCs. Applicants can choose from either of the three types of digital signature certificates, depending on their purpose and requirements.

  • Class 1 Certificate: They are issued to private subscribers to confirm that the user’s details fall within the CA’s database. They require either an Aadhaar eKYC biometric or paper-based application form with supporting papers, or an Aadhaar eKYC OTP & video verification.
  • Class 2 Certificate: These certificates are issued to signatory authorities for the purpose of e-filing with the ROC i.e., the Registrar of Companies. They require Aadhaar eKYC biometric or paper-based application form and supporting documents, or Aadhaar eKYC OTP & video verification. 
  • Class 3 Certificate: Used by vendors to bid in e-auctions and online tenders in India. They need an Aadhaar eKYC biometric or paper-based application form, supporting papers, and either a physical personal appearance before CA or Aadhaar eKYC OTP and video verification.
  • Aadhaar eKYC- OTP-based certificate: They require only an Aadhaar eKYC OTP.
  • Aadhaar eKYC- Biometric-based certificate: They require only Aadhaar eKYC Biometrics. 

How Does a DSC Work?

A digital signature certificate associates the identity of an individual explicitly with a pair of electronic keys. The pair includes a private key and a public key which is endorsed by the Certifying Authority (CA).

The DSC contains information about the user’s identity. It carries information such as the name, country, PIN code, email address, the date on which the certificate was issued, and the certifying authority’s name.

The pair of electronic keys are endorsed by CAs. They complement each other and one does not function in the absence of the other. Browsers and servers use these keys to encrypt and decrypt the data regarding the certificate user’s identity during the information exchange process.

The public key associated with the digital certificate is retained on the user’s device or an external token. The control of the private key is maintained by the user and it can only be used with the issued password.

The public key is dispersed with encrypted information. The authentication process for the eSigned document will fail if the public and private keys do not match or if either one of them is not available.

This encryption method ensures that the encrypted data is not decrypted by unauthorized parties as the document would be inaccessible to them.

How Digital Signature Certificates Work 

How Digital Signature Certificates Work

Methods of Obtaining a Digital Signature Certificate 

  • If applicants require a digital signature certificate they can directly approach the Certifying Authorities (CAs). They need to have the original supporting documents as well as the self-attested copies handy for this purpose.
  • Applicants can also obtain digital signature documents using Aadhaar eKYC-based authentication.
  • A letter certified by a bank manager containing the digital certificate applicant’s information that is retained in the bank database can also be accepted for the process of obtaining a digital signature certificate.

A DSC is legally valid across the country and one can avail of a digital signature certificate online for the required purpose.

Advantages of Digital Signature Certificates

  • The document is Authenticated Securely: When business transactions are carried out digitally, a DSC helps authenticate the personal details of the individual holder to a high degree of authenticity
  • Reduced Time and Cost: A digital signature certificate holder does not have to be physically present to carry out or authorize a business transaction. This helps reduce the time and also the cost required to complete a transaction. 
  • Authenticity: The certificate gives an assurance to the recipient that the document has been signed by the intended person. They can take further action on the digitally signed document without the need to be concerned about it being forged. 
  • The integrity of Data: A digital signature certificate ensures that the document cannot be edited or altered after it has been eSigned. This adds a layer of security to the documents which are often highly confidential in nature. 
  • Easy Verification: The certificate holder or the recipient can present the DSC to government agencies as they facilitate quick verification of the business transaction if ever needed.


A certificate serves as a proof of identity of an individual for a particular purpose; similarly, a digital signature certificate serves as a digital proof one can present electronically. Authorized users can not only present a DSC to sign a document digitally but also for proving their identity and access certain data or services on the internet. 

Users can avail of the benefits of this digital certificate through Electronic Signature software providers like SignDesk that allow them to eSign documents online from anywhere and at any time.