TFU is a three-letter acronym that can stand for: IATA code for Chengdu Tianfu International Airport Task Force Uruzgan, a Dutch reconstruction team in Afghanistan Three Forms of Unity, a set of Ca
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 0x8c11899ef9411212e5c16fe0cb81766181510ac982e08401fd1545372031a28d. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/e0bb5cfa-675b-4aae-8d16-6dc92b5e85b3.json and https://artists.proofprofile.net/proofs/artist/e0bb5cfa-675b-4aae-8d16-6dc92b5e85b3.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).