Vendor-neutral template

Functional requirements, not a prescribed product.

These requirements describe outcomes that Universal Document or a competing solution may attempt to satisfy. They do not require or imply selection of Universal Document.

1. Preserve an immutable identifier and cryptographic digest for the exact document state presented for signature.
2. Support authorized revision history with parent linkage and prevent silent rewriting of prior revisions.
3. Keep the credential private key within approved credential hardware/middleware and never embed it in the document.
4. Represent document integrity, signature validity, credential trust, identity assurance, time assurance and revocation separately.
5. Produce a portable final record whose integrity can be verified without dependence on the originating transaction portal.
6. Reject a signature when the document state differs from the state that was signed.
7. Preserve amendments as new derived records rather than overwriting the signed final record.
8. Provide machine-readable structured content and documented accessibility test evidence.
9. Support offline/local verification and disclose every required network dependency.
10. Provide a PDF compatibility representation without making the PDF copy the sole authoritative evidence object.
11. Publish schemas, canonicalization rules, test vectors and interoperability expectations sufficient for independent implementation.
12. Export audit and records metadata using documented, non-proprietary interfaces.