Tafel is a surname, and may refer to: Albert Tafel (1876–1935) German geographer, doctor and explorer Edgar Tafel (1912–2011), American architect Gustav Tafel (1830–1909), German-born colonel in the
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 0x88af37a8dec3a0e1dca5e0cb3a0d5b40c2261d8f471b1c7cf0c94895e35ff3f5. Chain 2 (Bitcoin): anchored in block 953941 (2026-06-16T11:51:19Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/213f9b3b-eb91-47e9-8bb9-f4e8aadbb8d6.json and https://artists.proofprofile.net/proofs/artist/213f9b3b-eb91-47e9-8bb9-f4e8aadbb8d6.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).