Sina may refer to: Relating to China Chin (China), or Sina (), old Chinese form of the Sanskrit name Cina () Shina (word), or Sina (), archaic Japanese word for China Sinae, Latin name for China
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 0xa77b9c2328c9d8c66b04c200fe3417859518ac3f7dc2ca6b4225aca4ad5dbcdc. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/36030ef6-79e4-4a3b-9729-0927f2e10ee0.json and https://artists.proofprofile.net/proofs/artist/36030ef6-79e4-4a3b-9729-0927f2e10ee0.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).