thumb|An Egyptian boomerang; National Archaeological Museum, Athens, Greece. thumb|Australian Aboriginal boomerangs A boomerang () is a thrown tool typically constructed with airfoil sections and desi
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x00db2ed137b88dcb169a2ca636c1dc5d0228a102e586db719f0fbe0d1eb2d2fc. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/828d0650-2681-4603-9902-96483dad16e6.json and https://artists.proofprofile.net/proofs/artist/828d0650-2681-4603-9902-96483dad16e6.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Best Ballads of Boomerang (5th Anniversary 1994-1999)