{
  "schema_version": "checkii.signing-keys.v1",
  "issuer": "checkii.ai",
  "updated": "2026-10-18",
  "notes": "Public keys that sign Checkii evidence, and the transparency log that records it. purpose is report-signature (issued report bundles and sealed exports), osint-transcript (DSSE-sealed governed-OSINT transcripts; the key identifier is the lowercase SHA-256 of the raw public key, which is the keyid the envelope carries) or transparency-log (the Rekor log key that signs the checkpoints in transparency.json; the key identifier is the lowercase SHA-256 of the key's DER encoding, which is the log id every entry carries). A key with status current signs evidence issued on the hosted service from its published date. A retired key verifies evidence issued between its published and retired dates only. A revoked key verifies nothing. A sample key verifies only the one demonstration bundle its binds field names, never a customer report or transcript. logged_from on a signing key is the date from which every statement it signs is entered in the transparency log; absent until the operator turns logging on. A key identifier appears at most once. Pin this file from a reviewed source; the copy of a key inside a bundle or download is never trusted on its own. A key with purpose transparency-signature is the ECDSA P-256 companion of the Ed25519 key its signs_for names (ADR 0090, amendment of 2026-10-18): it signs that key's transparency-log entries only, its identifier is the lowercase SHA-256 of its DER encoding, and it rotates with the key it accompanies. logged_from on a signing key is the first day from which every issuance under it is expected to carry a log entry.",
  "keys": [
    {
      "key_id": "published-sample-2026-09-21",
      "purpose": "report-signature",
      "algorithm": "Ed25519",
      "public_key": "ej3Q17iz9kD4ghCyYU6Iryb6kY6cEVac5C6h/a9siUw=",
      "status": "sample",
      "published": "2026-09-21",
      "binds": {
        "report_id": "1867c265-bcd8-4d2d-ba80-2f46fdb7fa93",
        "markdown_sha256": "f467dc9c188364d2f7d965352f8d882aa434a6464ef904c5a0577882602462bc",
        "snapshot_sha256": "24a406b47d5b6272fec93f8dc23c73acd13ce9daff8e222af0a5e6de89eebc87"
      },
      "signs": "The synthetic sample bundle at https://checkii.ai/sample/ only. Its private key was generated transiently and never exported."
    },
    {
      "key_id": "report-beta-7f382aaa",
      "purpose": "report-signature",
      "algorithm": "Ed25519",
      "public_key": "UU1RdR2AFxy1eQnPkVwTxVlgSl50fmR921sgRodciT8=",
      "status": "current",
      "published": "2026-09-12",
      "signs": "Report signature bundles and sealed exports (release receipts, verified-fix exports, CRA readiness packs) issued by the hosted service at https://api.checkii.ai since 2026-09-12. Read from the running platform on 2026-10-16, never typed.",
      "logged_from": "2026-10-19"
    },
    {
      "key_id": "4f5395901fea1f7d8f73c87a59f8a83eb0986da073781983bc0a8aea0a493009",
      "purpose": "osint-transcript",
      "algorithm": "Ed25519",
      "public_key": "mqrliNtqw+4aHWpvQ5OxtvRTbxr202dDSCSCpxBj0b4=",
      "status": "current",
      "published": "2026-09-12",
      "signs": "DSSE-sealed governed-OSINT transcripts issued by the hosted service since 2026-09-12. The key is derived from the same root as report-beta-7f382aaa with its own domain tag and rotates with it; the key identifier is the SHA-256 of the raw public key.",
      "logged_from": "2026-10-19"
    },
    {
      "key_id": "c0d23d6ad406973f9559f3ba2d1ca01f84147d8ffc5b8445c224f98b9591801d",
      "purpose": "transparency-log",
      "algorithm": "ECDSA-P256",
      "public_key": "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE2G2Y+2tabdTV5BcGiBIx0a9fAFwrkBbmLSGtks4L3qX6yYY0zufBnhC8Ur/iy55GhWP/9A/bY2LhC30M9+RYtw==",
      "origin": "rekor.sigstore.dev",
      "log_url": "https://rekor.sigstore.dev",
      "status": "current",
      "published": "2026-10-16",
      "signs": "Checkpoints of the public Sigstore Rekor log, in which Checkii enters the digest, signature and key of every issued statement (ADR 0090). The key was read from https://rekor.sigstore.dev/api/v1/log/publicKey on 2026-10-16 and is pinned in the verifier page as well; the page refuses a log whose registry key and pinned key disagree."
    },
    {
      "key_id": "86610f96991cf3859eb1bd310e948a3d329cad23edd74b200787c095ad9d5bde",
      "purpose": "transparency-signature",
      "algorithm": "ECDSA-P256",
      "public_key": "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEiAVr1nxZTdl+oY2EFxZC1GpNCAQ/RySHhnCEFCcFUCLSrwGQPbqrLyQMZqUgK2+Z4YW09C4zFmyp+6L4KGpGMg==",
      "status": "current",
      "published": "2026-10-18",
      "signs_for": "report-beta-7f382aaa",
      "signs": "Transparency-log entries (ADR 0090) for statements signed by report-beta-7f382aaa: the ECDSA P-256 companion signs the same canonical statement bytes, which the public Rekor log verifies over their SHA-256. It signs log entries only, never a bundle, seal or transcript, and rotates with the key it accompanies. Read from the running platform on 2026-10-18, never typed."
    },
    {
      "key_id": "9c2660a2cfcce78ed8a8e3cdb1f56ff53415b7862ef94b659d47912eaef342c7",
      "purpose": "transparency-signature",
      "algorithm": "ECDSA-P256",
      "public_key": "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEQ8SetNpgVAh7ldc88kS+TREZOGzbER6NgHBviptOKYMjFNpLdQ1Z4btcE46jkDJIweard6WCIQ5T0qZO6SlatQ==",
      "status": "current",
      "published": "2026-10-18",
      "signs_for": "4f5395901fea1f7d8f73c87a59f8a83eb0986da073781983bc0a8aea0a493009",
      "signs": "Transparency-log entries (ADR 0090) for governed-OSINT transcript envelopes signed by the transcript key: the ECDSA P-256 companion signs the DSSE pre-authentication encoding, which the public Rekor log verifies over its SHA-256. It signs log entries only and rotates with the key it accompanies. Read from the running platform on 2026-10-18, never typed."
    }
  ]
}