PRK can refer to: North Korea, ISO 3166-1 alpha-3 code Photorefractive keratectomy, laser eye surgery Phase reversal keying, a form of phase-shift keying People's Republic of Korea, short-lived 1
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 0x5ca644237fef77df4378c64c63bf2c6b1dbc157c7d6c67b8ed4dedc66f8c9457. Chain 2 (Bitcoin): anchored in block 953625 (2026-06-14T11:37:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/271ce6c7-7013-4194-a376-4cb33e803661.json and https://artists.proofprofile.net/proofs/artist/271ce6c7-7013-4194-a376-4cb33e803661.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).