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 0xc765908200026b75607de9714dabd7e158a01e99512eead13599a40f90bb516a. 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/d2048af1-8038-4d18-b912-99b323dbade6.json and https://artists.proofprofile.net/proofs/artist/d2048af1-8038-4d18-b912-99b323dbade6.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 0x8e0f770a52fa9044c708d3d352c54ec75e00919587eff38c7ef1fe5dfe87b315. Chain 2 (Bitcoin): anchored in block 960121 (2026-07-29T15:22:21Z), 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/GBWUL2463691.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb06e7d0f8365bbf6f56dd29556a8e8257824f267df3edc14f6f304844518e688. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/QZTB32367456.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0373c7584131885b0d125d0ac35be4c19f58651625024cb5ea88d39fb7f103b9. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/FRX202403282.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x834e029b1bdf948986995b0e7b3c96fde142227f004d5c0e15f91943c6f94c92. Chain 2 (Bitcoin): anchored in block 960339 (2026-07-31T03:13:37Z), 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/GBLFP2477411.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x165574abbefb26972e69ec4796fea28877cf50e7202bd023a3acf1b36740b940. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/FR10S2476962.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc6c4ad0ad0daad6b8d2ace4dae1b46f6c2ca2d8e73a5cc5dcd7d17d720c029a5. Chain 2 (Bitcoin): anchored in block 960273 (2026-07-30T15:42:38Z), 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/GBKQU2385491.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe84cdc48b252bac4df72080d9be3c58608213fc125d57ee82d24aece1906fabc. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/QZHN72440863.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x495780833114190e0748a023118f21652e3450e3d517684378ce19028cb18b2e. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/QZWFN2385300.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc9201f25b938d3056fb5f0a57cc55b1adf42de764afbf8412fba83e07776feda. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/QZTBC2388277.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x415ba7a499f470cfcaa55d3329d71a9b6dc824b36336b6ca3a4d60dc7db4ac7a. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/QZWV32326894.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb06e7d0f8365bbf6f56dd29556a8e8257824f267df3edc14f6f304844518e688. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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/QZTB32367456.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7cfa70aab8c6fb30df589336344c094ae593397f933407a3057e0021f6844a8f. Chain 2 (Bitcoin): anchored in block 960236 (2026-07-30T09:37:10Z), 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/GBKQU2385476.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5fddce34baf81875db09520e666828a231a85daba39a1cf8ae275459535e9d4f. Chain 2 (Bitcoin): anchored in block 960284 (2026-07-30T17:23:26Z), 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/CA5KR2183397.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd9389d497d228b9139fcab0d7302070dce16625333b2e96031d1887d469324ce. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/QZWDE2434428.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d23b02aa5b8a0497b6dfdb1af6119e6cfc222689377b114970c6ce8280368cd. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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/QM42K2192528.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa49e2a7f2b9ed8df809512805cb735f6fa1907c9f18c17a9b08ac9b92b69d8fd. Chain 2 (Bitcoin): anchored in block 957032 (2026-07-07T11:43:09Z), 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/FRX281936604.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe03c71884bd7a85615ff19363f2844005b08765471c2c66c64c44a014ed16153. Chain 2 (Bitcoin): anchored in block 960494 (2026-08-01T01:44:32Z), 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/GBKQU1709351.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf0d23369225607efc9f70591a13b4835635725280d01bc727cba4eee9da102d6. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/GBKQU1709353.