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Clause50EU AI Act evidence — starting with Article 50.EU AI Act evidence, starting with Article 50
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Evidence

You don’t have to trust Clause50 to verify a Clause50 artifact.

Evidence, in this product, is a record of what was true about an AI system, bound to the obligation it answers, that cannot be edited afterwards and can be checked by anyone. This page is the whole idea in one place — and a real artifact to check.

A real artifact, for you to check

Below is a complete Article 50 evidence pack for a fictional energy retailer’s support chatbot, and a risk classification memo for a fictional agency’s image generator with four open gaps. Both are signed with our specimen key and marked “specimen — not evidence” on every page; both verify at /verify.

Article 50 evidence pack — Ostrahaven Energy (specimen)

A support chatbot, one open gap.

The opening of the Ostrahaven Energy specimen Article 50 evidence pack: the specimen strip, the title, the coverage summary and the system identification table.
The opening of the real file, rendered from the ZIP’s own markdown — specimen, not evidence.
Download specimen (.zip)

Risk classification memo — Sablewick Studio (specimen)

A campaign image generator, high-risk-adjacent, four open gaps.

The opening of the Sablewick Studio specimen risk classification memo: the specimen strip, the title and the derived classification.
The opening of the real file, rendered from the ZIP’s own markdown — specimen, not evidence.
Download specimen (.zip)

Each ZIP contains the signed document (DOCX + PDF), the manifest bundle (manifest-bundle.json), and a VERIFY-THIS-PACK.md with the steps to check it yourself, offline. Upload manifest-bundle.json at /verify to see it verify live.

Follow one requirement through the specimen

Pick a requirement from the Ostrahaven pack. Below it: the evidence it rests on, that evidence’s hash, the entry in the signed manifest, and what /verify says about the whole pack.

3 more requirements are not applicable to this system, and say so in the document.

1 · Requirementspecimen
Art.50(1) — Disclosure implementationsatisfied

Read from the signed document of Ostrahaven Energy (specimen)’s demo — support assistant (chatbot), rule pack 2026.19.

2 · Evidence it rests onspecimen
  • 2-ostrahaven-assistant-disclosure-v1.pdfDoc upload · in the pack's evidence/ folder · recorded 18 Sept 2026
  • Attestation — a statement, not a fileIts full text is in the document's evidence register · recorded 18 Sept 2026
3 · Content hashspecimen
  • Content hash — the evidence chain’s hash of the whole item7290d41d48d23b5e035db7f2151e4cb03db53c9303588045c2b031578a8984e9File sha256 — re-compute it yourself with sha256sum0dc707eab5591a7703aaaf50bf1455daff435de9f43e2a6838a24736f8411bbb
  • Content hash — the evidence chain’s hash of the whole item9ac43a7845d091055765c5aa27fd919f3b2efb22d1d35dd3bcb4dbca04a29f50
4 · Signed manifest entryspecimen
{
  "id": "cmu6ekd53000aga1k3tlvemm4",
  "recordedAt": "2026-09-18T03:32:22.023Z",
  "contentHash": "7290d41d48d23b5e035db7f2151e4cb03db53c9303588045c2b031578a8984e9",
  "requirementKeys": [
    "disclosure_implementation"
  ]
}
{
  "id": "cmu6ekdjj0028ga1k92zzrh1s",
  "recordedAt": "2026-09-18T03:32:22.543Z",
  "contentHash": "9ac43a7845d091055765c5aa27fd919f3b2efb22d1d35dd3bcb4dbca04a29f50",
  "requirementKeys": [
    "disclosure_implementation"
  ]
}

As it appears in manifest-bundle.json, signed with the key key-specimen-test.

5 · Verificationspecimen
/verify · no account needed
✓ Valid — Clause50 specimen document (not evidence)
  • Manifest found
  • Key in registry
  • Signature valid
  • Markdown matches
  • DOCX matches
  • PDF matches
  • Specimen claim agrees with key

Valid signature — this is a Clause50 SPECIMEN document, generated from a demo system. It has not been altered since it was generated, and it is NOT evidence about any real AI system.

Download this pack and check it at /verify — the result above is what that page says about it.

What “EU AI Act evidence” means

An obligation names what must be true. Evidence is what shows it was — a document, an attestation against a checklist, a record pulled from a connected system, or an event your own systems sent. Each is bound to the requirement it answers.

The lifecycle

AI systemyou describe it
Risk classderived, you confirm
Applicable obligationsin force / from 2027
Evidenceappend-only
Signed evidence packEd25519-signed
Public verificationat /verify, no account

Where evidence comes from

Uploads, attestations, read-only connectors (usage reports from your model provider, a repository, an S3 log export) and an ingest API. Capability level only — the setup is in the product.

Evidenceostrahaven-assistant-disclosure-v1.pdfUpload
specimen
EvidenceA usage reportRead-only connector
specimen
EvidenceA checklist, signed by nameAttestation
specimen
Hash and bind
Content-hashed, bound to the system version
The bytes are hashed the moment they arrive; the hash is what the document cites.
Append-only record
Recorded once, never edited
No update, no delete — enforced in CI, migrations included. A mistake is retracted with a new entry that says so.
Requirement mapping
Bound to the requirement it answers
Every requirement in a signed document names the evidence its status rested on, by content hash.
Signed manifest
Ed25519-signed, over the whole bundle
Signed artifact · specimenArticle 50 evidence pack
  • Every requirement cites its evidence by hash
  • Manifest bundle inside the ZIP
/verify
Anyone can check it — no account

Obligation → evidence

Every requirement in a signed document names the evidence its status rested on, by content hash — not a summary written afterwards.

Requirement · Art. 50(1)Disclosure of AI interaction
Evidence present
rests onsha256 8e31…9f2aspecimen
Evidenceostrahaven-assistant-disclosure-v1.pdfUpload · captured 14 Sep 2026
specimen
sha256 8e31…9f2aappend-only
Signed artifact · specimenArticle 50 evidence pack
  • This requirement's status cites this hash
  • Ed25519-signed manifest over the whole bundle
  • Verifiable at /verify without an account

Kept, then signed

Append-only, by construction

No update, no delete — enforced in CI, migrations included. A mistake is retracted with a new entry that says so; the original stays.

Signed

Every finalised artifact carries an Ed25519-signed manifest over the whole bundle.

Verification — what it proves, and what it does not

It proves the bundle you hold is byte-for-byte what Clause50 signed, and when. It does not prove the evidence is true, complete, or that the system is compliant — those are the operator’s statements, and the document says whose they are.

Verify a pack →

Signed artifact · specimenArticle 50 evidence pack
  • Ostrahaven Energy · specimen
Inside the ZIP
manifest-bundle.json
The signed manifest and the hashes of every file it covers.
Upload it at
/verify
Verified in your browser; the only request is for our published key.
/verify · no account needed
✓ Valid — Clause50 specimen document (not evidence)
  • Manifest found
  • Key in registry
  • Signature valid
  • Markdown matches
  • DOCX matches
  • PDF matches
  • Specimen claim agrees with key

What stays yours

  • The quality management system (Article 17) — operating it stays yours; we record its documentation now, for the duty that applies from 2 December 2027.
  • Conformity assessment (Article 43).
  • EU database registration (Articles 49 and 71).
  • The fundamental rights impact assessment (Article 27).
  • Running post-market monitoring (Article 72) — we evidence what you did.
  • Running Article 4 AI-literacy measures — we record what you did.
  • Following your Article 26 deployer duties — we record your evidence of them now, for the duty that applies from 2 December 2027.
  • Signing the declaration of conformity (Article 47).

Clause50 is an EU AI Act evidence platform. It classifies an AI system against the whole Act from one intake — prohibited practices under Article 5 are refused, high-risk systems are screened against all eight Annex III areas and documented across the nine sections of the Annex IV technical file, and the four Article 50 transparency duties are evidenced — and it answers every obligation that applies with append-only, Ed25519-signed evidence that anyone can verify without an account. It records evidence against the 2027 high-risk obligations today, so the file exists on the day they bind — or on the day a significant change brings a legacy system into scope. It pre-fills the EU declaration of conformity and refuses to sign it. It is not the quality management system, conformity assessment, EU database registration or the fundamental rights impact assessment — those stay yours, whichever tool you use.

Classify a system — free