thumb|upright=1.35|Artist's image of the accretion disc in ULAS J1120+0641, a very distant quasar containing a supermassive black hole with a mass two billion times that of the Sun thumb|The Chandra X
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 0xfca0a14e1dafa86e6e0c81bb700d6b92e5a9f216f4fdf1e15ed85e08c79fd32f. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0f20daf6-fdb4-4a45-9b26-9193be076809.json and https://artists.proofprofile.net/proofs/artist/0f20daf6-fdb4-4a45-9b26-9193be076809.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 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 0xe8b3a41917f9d390a0ea41c9500d29f8ed75dae63cc88586e9f49e751233db58. Chain 2 (Bitcoin): anchored in block 958058 (2026-07-14T20:20:34Z), 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/QZ5FN1785366.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e9112aa14706b153dd90cb811ff27e17b2c5f85865d87c076d246dee36baf86. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/QZ5FN1785370.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d1ddc3096d23be386a40403cf8dd7fe7dd0133588f725c8fa49bd4ddaddd210. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/QZNWS2254653.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x50e312ac00e1621bcdd25a5503707da8f5d523c2b18db825f93dceaac4e598d8. Chain 2 (Bitcoin): anchored in block 957546 (2026-07-11T09:35:53Z), 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/QZES92501355.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x768ed960c860a49a57ea41ca45bc2e4b9df2852204b1f62f3c4af51bd73e1e36. Chain 2 (Bitcoin): anchored in block 958805 (2026-07-20T02:22:58Z), 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/QZK6F2513215.