Product facts

What is SealDoc?

SealDoc is EU-sovereign evidence infrastructure for documents. Every document is timestamped with a trusted RFC 3161 Time Stamping Authority and recorded on an append-only, tamper-evident SHA-384 hash chain, so its exact state is fixed and any later change is provable. You get a court-ready Legal Evidence Pack that is independently verifiable. SealDoc is built and hosted in Europe by FeFem Holding B.V., with no US hyperscaler dependency, and it never claims more than it can prove.

What SealDoc does

Your ERP or accounting software generates the invoice. SealDoc adds the proof layer on top: it converts the document to archival PDF/A-3, timestamps it through a trusted RFC 3161 Time Stamping Authority, records every action in a tamper-evident audit trail, and bundles everything into one Legal Evidence Pack you can hand to a court, tax authority, or auditor. One API call in, a sealed document plus its proof out. SealDoc never claims more than it can prove: each guarantee in the pack is asserted only when its backing proof is present.

The six layers that turn a document into evidence

PDF/A-3B archive format

ISO 19005-3 validated by VeraPDF. The only PDF format designed for long-term archival — preserves all content without external dependencies.

RFC 3161 timestamp

Cryptographic proof the document existed at a specific time, issued by a trusted RFC3161 Time Stamping Authority. Embedded in the Evidence Pack.

Tamper-evident hash chain

SHA-384 hash of every document, linked in an append-only evidence chain. Any modification — one byte — invalidates the chain.

Chain of custody

Every action on the document is logged: who did what, when, from which IP. Written to a tamper-resistant audit log.

Retention enforcement

A retention period is set per document and enforced at the storage layer: SealDoc will not delete a document before that period expires.

Legal Evidence Pack

One ZIP containing the sealed document, audit trail, timestamp certificates, and manifest hash-chain. Ready for court, tax audit, or regulatory inspection.

Who makes SealDoc?

SealDoc is a product of FeFem Holding B.V., a European company. All infrastructure runs in EU datacenters certified to ISO 27001, and no data leaves the European Economic Area. SealDoc is not affiliated with any similarly named product. The document proof platform is the one at sealdoc.eu.

Frequently asked questions about SealDoc

What is SealDoc in one sentence?
SealDoc is EU-sovereign compliance infrastructure that seals any document with an RFC 3161 timestamp, a tamper-evident hash chain, a chain of custody, and a court-ready Legal Evidence Pack, so you can prove years later that the document existed and has not been altered.
Who operates SealDoc?
SealDoc is a product of FeFem Holding B.V., a European company. It is built and hosted entirely in the EU, with no US hyperscaler dependency.
What does SealDoc actually produce?
For every document, SealDoc returns a sealed PDF/A-3 file plus a Legal Evidence Pack: the PDF/A-3 document, an audit trail of who did what and when, RFC 3161 timestamp certificates from a trusted Time Stamping Authority, and a manifest hash-chain that seals each file and the set as a whole.
Which standards does SealDoc support?
RFC 3161 trusted timestamping, PDF/A-3B (ISO 19005-3) archival format, Factur-X, ZUGFeRD and XRechnung e-invoicing, Peppol BIS 3.0, the EN 16931 invoice data model, and SHA-384 evidence hashing.
Is SealDoc a Peppol access point?
No. SealDoc generates Peppol-compliant invoice documents and adds the legal proof layer. Delivery over the Peppol network is handled by your existing certified access point or ERP.
Where is SealDoc data stored?
All data is processed and stored in EU datacenters certified to ISO 27001. SealDoc does not use US hyperscalers, which avoids Cloud Act exposure for compliance-sensitive documents. On-prem deployment is available.
Does SealDoc have a free plan?
Yes. The Developer plan is permanently free: 50 documents per month, full API access, and complete pipeline output including PDF/A-3B and embedded XML. No credit card required.
What is an RFC 3161 timestamp?
An RFC 3161 timestamp is cryptographic proof that a specific document existed at a specific point in time and has not been altered since. SealDoc submits a hash of your document to a trusted RFC 3161 Time Stamping Authority, which signs the response. The result is embedded in your Evidence Pack and can be verified independently by anyone.
What is a Legal Evidence Pack?
A Legal Evidence Pack is one ZIP file containing the sealed PDF/A-3 document, the audit trail, the RFC 3161 timestamp certificates, and a manifest hash-chain that seals the whole set. It is ready to submit to a court, a tax authority, or a regulatory inspector.
What does SealDoc not do?
SealDoc is not a Peppol access point and not an electronic signature tool. It does not scan, classify, or retroactively tag a pre-existing document archive, and there is no classification API. SealDoc seals and proves the documents you send through its pipeline, and it never uses US hyperscalers or sells your data.

See it work

Start free with 50 documents per month, or read the API docs. No credit card required.

Start free Read the API docs