Sundo - also known as Kouk Sun Do (국선도) - is a Korean Taoist art based on meditation, and which aims at the personal development of its practitioners, both at the physical, mental and spiritual levels
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 0x287cd1ea60584e76ec3cf66f9b7c439916e79443f6a78ca65d14172216afa351. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b1edc9de-95ab-4286-a20f-e3c85d65a10d.json and https://artists.proofprofile.net/proofs/artist/b1edc9de-95ab-4286-a20f-e3c85d65a10d.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).