Stockwell is a district located in South London, part of the London Borough of Lambeth, England. It is situated south of Charing Cross. History thumb|A map showing the Stockwell ward of Lambeth Metr
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 0x733a6bc9db01f0e5c156fcaec2128b46e49c9d32c4521dfa3572e461b8252bc0. Chain 2 (Bitcoin): anchored in block 953911 (2026-06-16T08:03:10Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/18945d6e-2e60-4ebb-b1ef-04b7602b2f79.json and https://artists.proofprofile.net/proofs/artist/18945d6e-2e60-4ebb-b1ef-04b7602b2f79.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.