Cortis (; stylized in all caps) is a South Korean boy band formed by Big Hit Music. The group consists of five members: James, Juhoon, Martin, Seonghyeon, and Keonho. Big Hit Music's third group aft
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 0xb321d29ad7df95ab42d60f326e3df65afba535af327be2a302becd0c8cf14188. 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/ad91f4cf-91c3-4a15-ba41-3d46d920596a.json and https://artists.proofprofile.net/proofs/artist/ad91f4cf-91c3-4a15-ba41-3d46d920596a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).