thumb|right|Franka sighting the ghost ship 'Northern Sun' in De Terugkeer van de Noorderzon, one of the early volumesFranka is a popular Dutch comic book series, drawn and written since the mid-1970s
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 0xc338e526134fee8b6f13098418f396bc3b5daa21fa680df2ec8a978e48b6e57b. Chain 2 (Bitcoin): anchored in block 953670 (2026-06-14T18:07:12Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/5971cc3d-b0bc-479a-b18e-3d2b808daf6d.json and https://artists.proofprofile.net/proofs/artist/5971cc3d-b0bc-479a-b18e-3d2b808daf6d.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 0x66205136b3dabdafd4706d1dc9e3171238e459164a9cdf9c78a1c18990f41b80. Chain 2 (Bitcoin): anchored in block 958969 (2026-07-21T04:58:13Z), 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/USL4Q1737987.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x69d63ced68c8acb4e188292c6f921e883de44c5c6468a0fae1337c4fcdc823ee. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/HRA431810101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbc674a850b66af1a216d583798e0c3de3de77bc700e8a9b45fbc2a1a71116bf4. Chain 2 (Bitcoin): anchored in block 959100 (2026-07-22T05:29:55Z), 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/HRA431810115.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x757a4baa6e34b767af10d56eeff8539e620e71827f2aabdb539c87e90254b7ad. Chain 2 (Bitcoin): anchored in block 958864 (2026-07-20T10:24:04Z), 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/HRA431810110.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8b7892ed046cafdb2f984674df16a9e7bb9974bda8d292638df15d714eb6fc9e. Chain 2 (Bitcoin): anchored in block 958523 (2026-07-18T08:54:12Z), 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/USL4Q1863415.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa00c92c217adbe31b3c7be5f1e10d01307882d450a046e1e23a202c7c43e0ad2. Chain 2 (Bitcoin): anchored in block 958796 (2026-07-20T00:01:46Z), 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/HRA041991194.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa344c3a5276991cdc4820c6e1c2e74ec39c780e32d74cd5e1bcd47d1061ff847. Chain 2 (Bitcoin): anchored in block 959043 (2026-07-21T18:40:26Z), 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/HRA042199150.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x26fbbb0e4e755579c0cf1ce3749bb0fcbc6e3468d76bcb8867ff7b76265fadf2. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/HRA042101447.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7c61b1c8ba259e4b96112c9bc1cd6359bc87674a59253e98a09bb3c3ece1d086. Chain 2 (Bitcoin): anchored in block 959105 (2026-07-22T06:33:30Z), 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/HRA042301616.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe67f54a36c164a4812e9a103b3e2346a81980fd4034860cf9568e55fb0858966. Chain 2 (Bitcoin): anchored in block 956397 (2026-07-02T21:02:00Z), 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/HRA042400729.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe67f54a36c164a4812e9a103b3e2346a81980fd4034860cf9568e55fb0858966. 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/HRA042400729.