{
  "height": 104,
  "block_hash": "3ac26fa1ad907488280538fdf04c365b5dec99564cbcefc9ddc5333c1afe2d62",
  "status": "confirmed",
  "bitcoin_block_height": 974888,
  "digest": {
    "alg": "sha256",
    "hex": "3ac26fa1ad907488280538fdf04c365b5dec99564cbcefc9ddc5333c1afe2d62",
    "preimage": "block:{\"at\":\"2026-11-07T03:23:00.436Z\",\"entry_count\":1,\"first_seq\":215,\"height\":104,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":215,\"merkle_root\":\"d1eb086a012df3366a3f5e6304195807964e037a65ccd2206347851f20d77556\",\"prev_hash\":\"be9b6546f6e1708103e3e509b5c16c84a45ca6ad801c4dad627220387b1baad3\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T03:28:43.476Z",
      "updated_at": "2026-11-07T05:28:43.487Z",
      "bitcoin_block_height": 974888,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee9aed2faf3504d904081aacb3cecd0645483d2ee09c1de3814132e5045493ca2f7a52fa2729bd50f865c5"
        },
        {
          "type": "bitcoin",
          "block_height": 974888,
          "merkle_root": "a373ea77dcacd26df989734c2bed34895920c60a915ed91eb73aa06c53238081"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T03:28:43.476Z",
      "updated_at": "2026-11-07T05:28:43.487Z",
      "bitcoin_block_height": 974888,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee9aeddcf45862688f4d3fb8ba372e4da63c5dc2c361be901a4ef99ad956680dceee1848b482e0c56ffba3"
        },
        {
          "type": "bitcoin",
          "block_height": 974888,
          "merkle_root": "a373ea77dcacd26df989734c2bed34895920c60a915ed91eb73aa06c53238081"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T03:28:43.476Z",
      "updated_at": "2026-11-07T03:28:43.476Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee9aedb1bea81ebd132c48ac36644862214d5977dc1a0363751bc8d7ca89d5371cbf53abd5bb9d50d91655"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/104/anchor.ots",
  "how_to_verify": "Download the .ots proof and run `ots verify -d <block_hash> <file>.ots` with the OpenTimestamps client, which checks the Bitcoin attestation against Bitcoin block headers. The digest is the block hash: sha256 of digest.preimage, the text \"block:\" followed by the canonical block header, which is the same header the issuer signs."
}