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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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x38d16c0da3667d0aafdcc45d049fbd437ea0a8d91b161402d6add3e565ec4bcc. Chain 2 (Bitcoin): anchored in block 953923 (2026-06-16T09:51:37Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/1c67f70f-d5c0-4f83-b7bc-9dd2cd38e014.json and https://artists.proofprofile.net/proofs/artist/1c67f70f-d5c0-4f83-b7bc-9dd2cd38e014.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).