Long-Term Validation (LTV)
Definition
A PDF signature profile (PAdES-LTV, ETSI EN 319 102-1) in which the OCSP responses, CRL data, and TSA certificate chain information are embedded alongside the signature at signing time, enabling full offline verification of revocation status years after the signing event.
- Standard
- ETSI EN 319 142-1 (PAdES-LTV)
- Embeds
- OCSP responses, CRL data, TSA certificate chain
- Embedded at
- Signing time
- Enables
- Offline signature verification years later
Common questions
Why is LTV needed if the signature already carries a timestamp?+
A timestamp proves when signing occurred, but the certificate and revocation chain behind it can still expire or become unreachable online later. LTV embeds the revocation evidence in the PDF itself so verification does not depend on a live OCSP or CRL server years afterward.
What happens if a PDF signature lacks LTV data?+
Once the signing certificate expires, verifying the signature may require fetching OCSP or CRL records that are no longer published, making the signature effectively unverifiable offline and harder to authenticate in later litigation.
Related terms
- Aadhaar E-Sign
- India's authentication-linked electronic signature service in which the user's Aadhaar biometric or OTP authentication triggers the generation of a short-validity signing certificate...
- ESIGN Act (Electronic Signatures in Global and National Commerce Act)
- US federal legislation (2000) providing that no electronic signature may be denied legal effect solely because it is in electronic form. Technology-neutral:...
- EU Trusted List (EUTL)
- The authoritative list maintained by the European Commission listing all Trust Service Providers per EU member state that are supervised to issue...
- OCSP (Online Certificate Status Protocol)
- A real-time certificate revocation protocol in which the verifier queries the CA's OCSP responder with the certificate's serial number and receives a...
- Public Key Infrastructure (PKI)
- The system of hardware, software, policies, and standards that manage digital certificates and public-key encryption. Provides the trust architecture underpinning all cryptographic...
- QSCD (Qualified Signature Creation Device)
- A hardware or remote HSM-based device that stores the signer's private key such that it cannot be extracted, ensuring sole control under...
- Qualified Electronic Signature (QES)
- The highest tier of electronic signature under EU eIDAS Regulation 910/2014. Created by a Qualified Signature Creation Device (QSCD), backed by a...
- TSA Timestamp (Timestamp Authority)
- A cryptographically protected record of the time at which a signature was created, issued by a Timestamp Authority (TSA) whose own certificate...
- X.509 Certificate
- A digitally signed data structure that binds a public key to a named identity (subject) and is issued by a Certificate Authority....