thumb|Hoàng Quyên in 2012 Hoàng Lệ Quyên (born 19 October 1992) is a Vietnamese singer who became known from Vietnam Idol season 4. The final was a competition between Hoàng Quyên and the best placed
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 0xcc8ac26e47b69838363a792931858be3e0fb07ff2d3d6e5b543873501f8237e4. Chain 2 (Bitcoin): anchored in block 954638 (2026-06-21T03:45:44Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d4ea7a4e-3df7-44c6-9bb7-ff044703d7fd.json and https://artists.proofprofile.net/proofs/artist/d4ea7a4e-3df7-44c6-9bb7-ff044703d7fd.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4bbe56513a92fde60da436920f67a949cb649ad7cd1416d0a93b4cd6f1a3c378. Chain 2 (Bitcoin): anchored in block 958286 (2026-07-16T12:43:37Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZ22B1895535.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x70f8aead000b56e4eb6b4e1ed424efd2b198c0ff981b1fa76015d94d994bf5bf. Chain 2 (Bitcoin): anchored in block 959002 (2026-07-21T14:02:32Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZ22B1895539.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1921d604b3c5259257efa63527408600d5198b0bfdcd049862eb791a705b2684. Chain 2 (Bitcoin): anchored in block 958765 (2026-07-19T20:05:46Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZ22B1927054.