TSP evidence · verifiable documentation

Trust Standard Protocol

Certificate evidence that can be verified, not just displayed.

This demo loads the latest certificate entry from the evidence chain and runs real signature and chain verification before showing status.

Verify public certificate View public key

Live verification

Signature

Verified

Chain up to entry

Failed

entries in chain
37 / 38
invalid entries
1

Certificate

Certificate code
LEXI-2026-AAB91C4CE775B169
Certificate type
Course
Certification reference
27

Participant name, email and raw payload are not shown in this public demo.

Evidence chain

PrevHash binds the entry to the previous signature. ContentHash binds event type, payload, prevHash and timestamp. The signature proves that the issuer key signed the hash value.

Previous entry

260

Current entry

261

Next entry

262

Signed fields

Event type
CertificateIssued
Created
2026-08-13T21:43:10Z
Algorithm
Ed25519+RFC3161-SHA256
Issuer key
ed25519-20260620-101301-845ddb6b
PrevHash
1497fc241aa9f8...811f3f6bfa
ContentHash
ff4817bc278f72...94ff506f2b
Signature
9Zl/d6xqZL9IEZ...HHOhEFAQ==

Values are shortened in the view. The full value is stored in admin and used by the verification logic.

How the evidence is verified

  1. 1. Locate certificate entry

    The demo loads the latest CertificateIssued entry linked to a certificate.

  2. 2. Verify signature

    ITspEvidenceService.VerifyAsync recalculates the hash and checks the Ed25519 signature.

  3. 3. Verify the chain

    VerifyChainAsync walks the full chain and checks that every PrevHash points to the previous signature.

  4. 4. Show safe diagnostics

    The public view shows status and technical fingerprints, but not personal data or raw payload.

What TSP means — and does not mean

The Trust Standard Protocol (TSP) is an open protocol that makes AI decision evidence durable, tamper-evident and verifiable offline — by anyone, without having to trust the vendor. Every event is signed with Ed25519, hashed with SHA-256 over canonical JSON (JCS, RFC 8785) and chained to the previous entry.

TSP verifies the integrity of the evidence — not whether the content is true, lawful or compliant. TSP does not make you compliant, does not prove that a model is correct or safe, and grants no official status. Payment never grants official status. The legal assessment remains with your DPO and legal advisers.

TSP is currently operated by LexiCo AS (Norway, EU/EEA) as operator and licensee — not as owner of the standard and not as a certification authority. The open layer (specification, test suites, verifiers, TrustBadge) is Apache-2.0 licensed.