What Is a Digital Signature (DSC)?
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What Is a Digital Signature?
A digital signature is an encrypted, mathematically verifiable way of signing an electronic document that proves who signed it and confirms the document hasn't been altered since signing. In India, a Digital Signature Certificate (DSC) — issued by a licensed Certifying Authority — is the credential that makes a digital signature legally valid, similar to how a notarised signature works on paper.
How a Digital Signature Works
A DSC uses public key cryptography: the signer has a private key (kept securely, often on a USB token) and a matching public key that others can use to verify the signature. When a document is signed, the private key creates a unique digital fingerprint tied to that exact document; if even a single character changes afterward, verification fails, which is what makes digital signatures tamper-evident in a way a scanned signature image never can be.
Where Digital Signatures Are Required
In India, DSCs are required or commonly used for company incorporation filings, GST and income tax returns, e-tendering, MCA (Ministry of Corporate Affairs) filings, and signing e-invoices in certain workflows. For businesses filing regularly with government portals, a valid DSC isn't optional — it's the mechanism that makes an online filing legally equivalent to a physically signed and stamped document.