Kang Dong-chul (, born June 7, 1979), also known by his stage name Brave Brothers, is a South Korean rapper, record producer and songwriter for Brave Entertainment. He was a producer and composer for
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 0xff055382b1a033d26565d4ee9e34287bbbed7b8be384fa3c3339290b73d9d284. Chain 2 (Bitcoin): anchored in block 954549 (2026-06-20T10:56:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/aa9d370c-e41f-4d73-8718-e01ddca568fd.json and https://artists.proofprofile.net/proofs/artist/aa9d370c-e41f-4d73-8718-e01ddca568fd.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).