Digital Signature is equivalent of a physical signature in an electronic format, as it creates the identity of a sender of a document on internet. Digital Signatures are used in India for online transactions such as Income Tax E-Filing, Company, Filing Annual Return, E-Tenders, etc. there are mainly three types of digital signature:

Class I
Class II
Class III

Class I – Class I type of Digital Signatures are only used for securing email communication.
Class II – Class II type of Digital Signatures are used for IT Company,Return E-Filing, Obtaining DIN, and filling other forms in the Ministry of corporate affairs.
Class III – Class 3 Digital Signatures are used mainly for E-Tendering and for participating in E-Auctions.

Digital Signatures come in the form of a USB E-Token, wherein the Digital Signature Certificate is stored in a USB Drive and can be accessed through a computer to sign documents electronically. Class 3 Digital Signature Certificate is the upgraded version of Class 2 Digital Signature Certificates participate in the e-tendering process; every vendor is required to use a Class 3 Digital Signatures Certificate.

However, class 3 digital Signature Certificate is also available in different types.
An individual user or an authorized individual on the behalf of organization or company or firm can obtain Class 3 DSC. These are categorized as: Individual User (Class 3A) & Company user (Class 3B). Further it is also mentioned in IT Act & legal status, both of these categories can be issued in two different certificates called signing certificate and Encryption certificate
Generally, class 3 digital signature is available with 1 year and 2 years validity.
By Using This Certificate, you can Participate/Bid in Any Kind of On-line Tenders/Auction across India.

Requirement of Digital Signature

It facilitates e-Procurement, integrates and streamlines procurement processes. From buyer to supplier and even back. Approved under the Law of Information Technology, and with legal personality, a certificate of digital signature is essential for all e-Procurement processes.

Request online government tender has many advantages. Since the documents are loaded into a central site, acknowledgments and receipts are provided immediately. Which it is not the case of paper documents to be scanned and verified before being processed.

Usage of Class 3 Digital Signature

1. A Digital Signature Certificate (DSC) is essential for companies and organizations that take part or intend to take part in E-tendering processes on various Government sites. Besides enabling E-tendering which is extremely convenient and transparent, a Digital Signature Certificate also ensures greater security in other online transactions.
2. For secure email and web-based transactions, or to identify other participants of web-based transactions.
3. To prove ownership of a domain name and establish SSL/ TLS encrypted secured sessions between your website and the user for web based transactions.
4. As a developer, for proving authorship of a code and retaining integrity of the distributed software programs.
5. For signing web forms, e-tendering documents, filing income tax returns, to access membership-based websites automatically without entering a user name and password etc.
6. Class 3 DSC is used for different kind of Registration.

Why do I need a Digital Signature Certificate?
A Digital Signature Certificate authenticates your identity electronically. It also provides you with a high level of security for your online transactions by ensuring absolute privacy of the information exchanged using a digital certificate. You can use certificates to encrypt information such that only the intended recipient can read it. You can digitally sign information to assure the recipient that it has not been changed in transit, and also verify your identity as the sender of the message.