thumb|A map of rivers and canals in and around Paris. The Ourcq (, Urc in 855) is an river in France, a right tributary of the Marne. Its source is near the village Ronchères, and its course crosses
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 0x507a2e9473555a8ddcce493a8d3329da2969254a8e0212732bb5fc2a20dbb2b1. 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/2065f5cd-15ff-42d1-98db-d09b74f1f895.json and https://artists.proofprofile.net/proofs/artist/2065f5cd-15ff-42d1-98db-d09b74f1f895.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 0x4210ae6b5b44fa1c2d192119457d1de93df7a6c8986d0007fedddca860e0244a. Chain 2 (Bitcoin): anchored in block 958224 (2026-07-16T02:28:43Z), 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/QZHN92237771.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x463f3a5be49c74b4a4b0e2fba1b5b02b8e8ad29181f60439704b0d2609edb109. Chain 2 (Bitcoin): anchored in block 958319 (2026-07-16T21:26:31Z), 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/USANG2232779.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc7b44e7e30b66a777ba9ca580b3428d7d6425e385b00235a354c2bd6f7511899. Chain 2 (Bitcoin): anchored in block 958316 (2026-07-16T19:42:29Z), 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/USANG2275890.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x411c986d04df72d54ff9f6e177e3a278c150eb65b04ce9301cd9043ed77520ee. Chain 2 (Bitcoin): anchored in block 958802 (2026-07-20T01:04:02Z), 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/QM3DF2211576.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc914c2952ff25c85cebec72d83d549ac151b32b50fc5f5e45ed3e6a2f631e6bc. Chain 2 (Bitcoin): anchored in block 958194 (2026-07-15T20:32:27Z), 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/QM3DF2298146.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf7ca76331f222e6e753e3be6a4f030fec0b768c54e5185e1f4a0afa24492224f. Chain 2 (Bitcoin): anchored in block 958224 (2026-07-16T02:28:43Z), 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/UKZGC2308133.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x869ec598cebd41ad36872d0273cbfe61f94c6ed65b8f90b1553ef3498bffbb71. Chain 2 (Bitcoin): anchored in block 956500 (2026-07-03T13:55:21Z), 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/GX5MX2341590.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x52ceaf4dc7965f1a1338525e633bd50b601ce4f9bb56a89402caa3e9d25ade4d. Chain 2 (Bitcoin): anchored in block 957882 (2026-07-13T16:48:10Z), 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/US3DF2434792.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb66285b174afb19dca01d3bc9e154adfe1257d887098f519fa320ce3fa0e24fa. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T12:00:19Z), 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/US3DF2434793.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf852f91c9f5c7df458cbb1209c296accfe23c844ccfeaab5a19e606269b74efb. Chain 2 (Bitcoin): anchored in block 958319 (2026-07-16T21:36:21Z), 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/US3DF2434791.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0ee36c12d3cbc0f03ce970b035d2d1d50893d2f8f8947491795fc21ab632ccf9. Chain 2 (Bitcoin): anchored in block 957805 (2026-07-13T04:34:37Z), 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/USANG2409974.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x17ac93837c98657fc962c072a27f2fcb73865656e9207bab23eae885c6b94b7a. Chain 2 (Bitcoin): anchored in block 953515 (2026-06-13T12:53:06Z), 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/US3DF2425219.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xee81e9a0fadac3b0136dabc2697ab02410398c919ae3cb6dd22f47700ea6d8d3. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/BCD4N2500028.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0f1c41367dab5efb9f748f14709955fcecefa3641143090fbdf582eceef150c0. Chain 2 (Bitcoin): anchored in block 960220 (2026-07-30T07:28:30Z), 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/USANG2248394.
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