GACEK
type: MusicGroup
description: Gacek (Polish: ) is a male domestic cat with tuxedo fur. Between 2020 and 2023, this homeless cat was a tourist attraction in Szczecin, Poland. In 2020, a video of Gacek was distributed around the wor
popularity: 5
followers: 6
additional property: CopyrightID
additional property: CopyrightChainExplorerURL
  type: PropertyValue
  value: https://explorer.copyrightchains.com/tx/0x939d4afb383266bcfe218cd1afa8b73ce2fbf50ac3f13d364f9b08a28172838e
additional property: OTSHash
additional property: OTSBitcoinBlock
  type: PropertyValue
  value: 953909
additional property: OTSBitcoinBlockVerifyURL
  type: PropertyValue
  value: https://blockstream.info/api/block-height/953909
additional property: OTSProofURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/0b9a1243-f6d4-4fb4-9c5e-abfcd642adcf.ots
additional property: OTSRecordURL
  type: PropertyValue
  value: https://artists.proofprofile.net/proofs/artist/0b9a1243-f6d4-4fb4-9c5e-abfcd642adcf.json
additional property: OTSVerificationAPI
  type: PropertyValue
  value: https://artists.proofprofile.net/api/v1/bot/ots/verify/artist/0b9a1243-f6d4-4fb4-9c5e-abfcd642adcf
additional property: OTSTimestamp
  type: PropertyValue
  value: 2026-06-16T07:53:13Z
additional property: OTSCanonicalRecord
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 0x939d4afb383266bcfe218cd1afa8b73ce2fbf50ac3f13d364f9b08a28172838e. Chain 2 (Bitcoin): anchored in block 953909 (2026-06-16T07:53:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0b9a1243-f6d4-4fb4-9c5e-abfcd642adcf.json and https://artists.proofprofile.net/proofs/artist/0b9a1243-f6d4-4fb4-9c5e-abfcd642adcf.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
  date published: 2026-06-16T07:53:13Z