The City of London Choir is a non-professional choir based in London, England. In 2024, Daniel Hyde (also Director of Music for the Choir of King's College, Cambridge) was appointed as Musical Direct
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 0x7a6378d5e7690f6e9970aef40091f950082153410cf97e8932b779426cda8f8b. 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/c20fa7ae-e010-4a76-9d7c-9f29ba32b1a3.json and https://artists.proofprofile.net/proofs/artist/c20fa7ae-e010-4a76-9d7c-9f29ba32b1a3.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).