沢井忠夫
type: MusicGroup
genre: japanese classical
popularity: 6
followers: 473
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x83e26b18ad4be13254588b726ae954bfc2bae809582ff729593fd23d288ec18d
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 954065
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/954065
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/490e6c14-b461-4db3-aa45-747b4aa51cec.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/490e6c14-b461-4db3-aa45-747b4aa51cec.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/490e6c14-b461-4db3-aa45-747b4aa51cec
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-17T08:10:43Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0x83e26b18ad4be13254588b726ae954bfc2bae809582ff729593fd23d288ec18d","name":"沢井忠夫","registered_at":"2026-06-16T15:05:04Z","symbol":"NIM1089430","token_address":"0x7e17fc7c062aad64e6306994339f2545296b352a","type":"artist","uuid":"490e6c14-b461-4db3-aa45-747b4aa51cec"}
additional property: OTSVerifyInstructions
  type: PropertyValue
  value: 1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x83e26b18ad4be13254588b726ae954bfc2bae809582ff729593fd23d288ec18d. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/490e6c14-b461-4db3-aa45-747b4aa51cec.json and https://artists.proofprofile.net/proofs/artist/490e6c14-b461-4db3-aa45-747b4aa51cec.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-17T08:10:43Z
  text: {"copyright_id":"0x83e26b18ad4be13254588b726ae954bfc2bae809582ff729593fd23d288ec18d","name":"沢井忠夫","registered_at":"2026-06-16T15:05:04Z","symbol":"NIM1089430","token_address":"0x7e17fc7c062aad64e6306994339f2545296b352a","type":"artist","uuid":"490e6c14-b461-4db3-aa45-747b4aa51cec"}
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