{
  "height": 72,
  "block_hash": "9f5ff8ea0f31605ca3bb9f8da8098543041492c4e80e13258c7e2ccaa07893e8",
  "status": "confirmed",
  "bitcoin_block_height": 972968,
  "digest": {
    "alg": "sha256",
    "hex": "9f5ff8ea0f31605ca3bb9f8da8098543041492c4e80e13258c7e2ccaa07893e8",
    "preimage": "block:{\"at\":\"2026-10-24T19:33:37.518Z\",\"entry_count\":1,\"first_seq\":74,\"height\":72,\"key_id\":\"key_41eb7b6d1b11968a\",\"last_seq\":74,\"merkle_root\":\"77d4efd75c7dc9d73e68f8a3dc64e1954f84143d14624264a48ba36874cffe2a\",\"prev_hash\":\"185410da5418bada627003dcb4515e03c329b7491ed2ac4d03606f05ee0a2f1f\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-10-24T19:43:06.805Z",
      "updated_at": "2026-10-24T21:37:52.447Z",
      "bitcoin_block_height": 972968,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6add0a4bb13da318f1f2438ef7350252395862051439bfc7ff3db2387fa253e78ee1815263038a94693d3971"
        },
        {
          "type": "bitcoin",
          "block_height": 972968,
          "merkle_root": "2a0afd342bd007efb1fc07905f9b010bb0dbfc7c9b9c619cb1902d45b6d9cff3"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-10-24T19:43:06.805Z",
      "updated_at": "2026-10-24T21:37:52.447Z",
      "bitcoin_block_height": 972968,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6add0a4b448894ecdde6dc570508e14520b1090d9218bf045054bb77eaba0f85c8ef9bdc84b0d706fe7c2fa6"
        },
        {
          "type": "bitcoin",
          "block_height": 972968,
          "merkle_root": "2a0afd342bd007efb1fc07905f9b010bb0dbfc7c9b9c619cb1902d45b6d9cff3"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "confirmed",
      "submitted_at": "2026-10-24T19:43:06.805Z",
      "updated_at": "2026-10-25T02:49:17.524Z",
      "bitcoin_block_height": 972999,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6add0a4c3436eb017e67bc40cedf46da8722011ed4d6f59b9ed36507f42b04b7926c07e64b556d8e1466b9fa"
        },
        {
          "type": "bitcoin",
          "block_height": 972999,
          "merkle_root": "ae0e717f0d642956016a8572888d23fb045efcac654b542c5ac908707f3b5590"
        }
      ]
    }
  ],
  "proof_url": "https://www.rightshold.com/v1/ledger/blocks/72/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."
}