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 0x339338ad5d7210b20b606939e6d89347e5632747f964166988e1b2c1a2545282. Chain 2 (Bitcoin): anchored in block 953888 (2026-06-16T04:55:23Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0ce56f59-4ffd-4ca7-af7b-f3d1430f0b35.json and https://artists.proofprofile.net/proofs/artist/0ce56f59-4ffd-4ca7-af7b-f3d1430f0b35.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.