Compliance
RFC 3161 Timestamping
Prove exactly when a document was signed
Cryptographic timestamps from independent Time Stamp Authorities — tamper-proof, court-admissible and applied automatically on every signature.
RFC 3161 · certified TSA · embedded token · long-term validity
Independent time proof, not just a server clock
RFC 3161 timestamps come from a trusted third party with its own certificate — stronger evidence than a system clock anyone can change.
Certified TSA tokens
Accredited Time Stamp Authorities issue cryptographic proof of the exact signing moment.
RFC 3161 standard
Implements the IETF RFC 3161 protocol used worldwide for trusted timestamping.
Embedded in the PDF
The timestamp token lives inside the digital signature for self-contained verification.
How trusted timestamping works
Every signed document can receive an independent, cryptographically signed time token automatically.
- 1
Generate document hash
When signing completes, WPsigner creates a SHA-256 hash of the signed document.
- 2
Request a TSA token
The hash is sent to your configured Time Stamp Authority via RFC 3161. The TSA signs a timestamp token with its certificate.
- 3
Embed the token
The signed timestamp is embedded in the PDF digital signature for anyone to verify.
- 4
Retain long-term proof
The timestamp remains valid even after your signing certificate expires.
Choose your Time Stamp Authority
WPsigner includes a default TSA configuration. Prefer DigiCert, GlobalSign, Sectigo, FreeTSA or another RFC 3161 endpoint? Point settings at any compliant TSA — no add-on fee.
- Tamper-proof time proof from an independent TSA
- Legal admissibility for disputes and IP priority dates
- Automatic application when documents are signed
- Multiple RFC 3161-compliant TSA endpoints supported
- Included in every WPsigner plan
Timestamping capabilities
- Certified TSA timestamps
- RFC 3161 compliance
- Tamper-proof time proof
- Token embedded in the PDF
- Court-admissible evidence
- Long-term validity after cert expiry
- Multiple TSA providers
- Automatic application on sign
When trusted time matters
Legal disputes
Prove the signature occurred at a specific, independently attested time.
IP and priority dates
Support claims where existence-at-time evidence is critical.
Regulatory audits
Provide verifiable timestamps that do not depend on your server clock.
Long retention files
Keep time proof valid after signing certificates expire.
Frequently asked questions
What is RFC 3161 timestamping?
RFC 3161 is an internet standard for trusted timestamping. A Time Stamp Authority (TSA) — an independent third party — issues a cryptographically signed token proving that a specific data hash existed at a specific time. This is stronger than a server clock timestamp because it comes from a trusted, independent source.
Why is trusted timestamping important?
Server timestamps can be manipulated by changing the system clock. RFC 3161 timestamps cannot — they come from an independent TSA with its own certificate. That matters in legal disputes, intellectual property claims and regulatory compliance where audit trails require verifiable time.
Does this cost extra?
No. RFC 3161 timestamping is included in every WPsigner plan with a default TSA configuration. You can configure any RFC 3161-compliant endpoint (DigiCert, GlobalSign, etc.) in settings.
How is this different from a regular timestamp?
A regular timestamp records time from your server clock, which admins can change. An RFC 3161 timestamp comes from a trusted third-party TSA with its own cryptographic certificate — independent, court-admissible proof of signing time.
Which TSA providers can I use?
Any RFC 3161-compliant endpoint — including FreeTSA, DigiCert, GlobalSign, Sectigo and others you configure in WPsigner settings.
Do timestamps survive certificate expiry?
Yes. RFC 3161 timestamps remain valid indefinitely, even after your signing certificate expires, supporting long-term archival use cases.
Certified timestamps on every document
RFC 3161 timestamping is included in every WPsigner plan. No add-ons required.
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