Mac Barnett
type: MusicGroup
description: Mac Barnett is an American children's book writer best known for his advocacy of the picture book. He has published over seventy works since 2009, consisting of over fifty picture books, graphic novel
popularity: 5
followers: 91
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x591c3ed05d85b444055037793fc16532d590d0427decb5ec5e1cd2fe8b856e62
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 954549
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/954549
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/a7449ee9-8d4e-4eae-8802-65801ded016f.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/a7449ee9-8d4e-4eae-8802-65801ded016f.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/a7449ee9-8d4e-4eae-8802-65801ded016f
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-20T10:56:20Z
additional property: OTSCanonicalRecord
  type: PropertyValue
  value: {"copyright_id":"0x591c3ed05d85b444055037793fc16532d590d0427decb5ec5e1cd2fe8b856e62","name":"Mac Barnett","registered_at":"2026-06-20T08:26:52Z","symbol":"NIM1565162","token_address":"0xd7290cc6795d8a60261e41721f7e7e229e3abb8d","type":"artist","uuid":"a7449ee9-8d4e-4eae-8802-65801ded016f"}
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 Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
subject of: OpenTimestamps Proof of Existence
  type: DigitalDocument
  encoding format: application/vnd.opentimestamps.ots
  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x591c3ed05d85b444055037793fc16532d590d0427decb5ec5e1cd2fe8b856e62. Chain 2 (Bitcoin): anchored in block 954549 (2026-06-20T10:56:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/a7449ee9-8d4e-4eae-8802-65801ded016f.json and https://artists.proofprofile.net/proofs/artist/a7449ee9-8d4e-4eae-8802-65801ded016f.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-20T10:56:20Z
  text: {"copyright_id":"0x591c3ed05d85b444055037793fc16532d590d0427decb5ec5e1cd2fe8b856e62","name":"Mac Barnett","registered_at":"2026-06-20T08:26:52Z","symbol":"NIM1565162","token_address":"0xd7290cc6795d8a60261e41721f7e7e229e3abb8d","type":"artist","uuid":"a7449ee9-8d4e-4eae-8802-65801ded016f"}
album: Mac Undercover [Mac B., Kid Spy, Book 1 (Unabridged)]
  type: MusicAlbum
  date published: 2020-09-17