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Verify Eichor — audit the attestation ledger

Do not take our claims on trust — check them. Eichor seals verified facts into a signed, hash-chained ledger the moment they are established. This page explains how the ledger works and how to audit it.

How the ledger works

• Each verified fact becomes a ledger entry carrying: the claim payload, a SHA-256 hash of that payload, the hash of the previous entry (the chain), a timestamp, and an HMAC signature.
• Because every entry contains the previous entry's hash, changing or deleting any historical record would break every hash that follows it — tampering is mathematically visible, not just against policy.
• At-risk trial calls are sealed the moment they are made, then scored against what the public registry later shows — confirmations and misses alike; the statistics are computed over the complete resolved set, with no per-record publish switch to hide behind. Public per-record lookup is not yet live — individual records are available by request until the scoreboard ships.

How to audit an entry

1. Take an entry's payload and compute its SHA-256 hash — it must equal the recorded payload hash.
2. Confirm the entry's chain hash equals the previous entry's record hash — repeat backward as far as you like.
3. Compare the entry's timestamp against the public registry record it references (for example, a trial's status history on ClinicalTrials.gov) — the seal always predates the outcome it predicted.

Doing this today

Public, per-record ledger lookup ships together with our track-record scoreboard (first audited reporting period closes soon — see track record). Until then: email hello@eichor.com with an attestation id and we will return the signed record for independent verification. The mechanism itself is described further at provenance.

Why this matters: any vendor can claim accuracy after the fact. A sealed, tamper-evident ledger is the difference between "trust our marketing" and "check our math."