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 0x29c2e972e2e848053f2856fa51623036d291edb43208f075292acc6f646d0102. Chain 2 (Bitcoin): anchored in block 954553 (2026-06-20T11:51:30Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/acc143d9-4f4b-40d6-9ddc-bc6d81f3337f.json and https://artists.proofprofile.net/proofs/artist/acc143d9-4f4b-40d6-9ddc-bc6d81f3337f.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
EP! (feat. Sietse van Gorkom, Camilla van der Kooij, Rani Kumar & Jonas Pap)