When a document is fully signed, Zoho Sign computes a cryptographic hash of the finalised PDF and writes that hash to a blockchain ledger. The resulting transaction ID and timestamp are recorded in the document’s evidence summary. Anyone holding a copy of the signed PDF can re-hash it and compare against the blockchain entry to confirm the document has not been altered since signing, providing verification that is independent of Zoho’s infrastructure.
Use blockchain timestamping for high-stakes agreements where a counterparty or regulator may later dispute the exact time of signing or whether the document was modified post-signing: large commercial contracts, property agreements, or compliance attestations. It is unnecessary for routine low-value documents where the standard audit trail and tamper-evident seal are sufficient, as enabling it adds processing overhead and may not be available on all plan tiers.
Blockchain timestamping is a premium feature in Zoho Sign and must be enabled at the organisation or document level; it is not on by default. The feature’s legal weight depends on the jurisdiction: in India, the IT Act 2000 and its amendments recognise electronic records, and a blockchain-anchored hash strengthens non-repudiation arguments, but courts ultimately decide evidentiary weight. Store the transaction ID alongside the signed PDF so you can present the verification proof independently.
No. Only a cryptographic hash of the document is written to the blockchain, not the document itself. The hash is a fixed-length fingerprint that cannot be reverse-engineered to reveal any content. The actual document remains in Zoho Sign’s secure storage and is never exposed on a public ledger.
Zoho Sign uses the Ethereum blockchain for its timestamping feature, writing the document hash as an on-chain transaction. The resulting transaction hash can be looked up on any public Ethereum block explorer to confirm the timestamp and hash independently, without needing access to Zoho’s systems.
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