Christian Köhler (13 October 1809 in Werben – 30 January 1861 in Montpellier) was a German painter, associated with the Düsseldorfer Malerschule, although his style owes much to the Nazarene movement.
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 0x9721d4e9a115fa03f034095f68a7cec2a747d0a96a7c5d3a4f76976db19fdc9c. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3ce297aa-ef61-4447-ba45-13d5758868b1.json and https://artists.proofprofile.net/proofs/artist/3ce297aa-ef61-4447-ba45-13d5758868b1.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 0x2faa86c50b584c8077b1df483db087362638a87e9d866addd98e048fb91066e2. 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/QMDA62492523.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x97c747d846a30bc7d56e2defb59c3d1cf1d8f8bb7d055b15657f1dc6dcf5602c. 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/QMDA62492517.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4db86274a11db473eccb4e101bdd4fe50f2d7390727cba1c954ea537e1a86c27. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QMDA62492504.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x38c8d193aaa959371599934201b38dc8ee980aada0d48b0cb96497240d493ed4. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QMDA62492476.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x68a5fc42d7fd75227da9fdf8651c6c3c49be17a21b6d1ce075e9d9edc2378cf0. 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/QMDA62492522.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x11e873f6119ded094ca615351d44c2358afdc6a0c880c31205d7469caec2b856. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QMDA62492472.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa1bb0e7197e0a144dcc8713983cbbd9c6bf8333cf67aa83c3453c36ae695ff90. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QMDA62492515.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf40a0c406daafe1ef11159df807183b325ef1793fb9343db86db659fe17256e7. 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/QMFMF2438784.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2faa86c50b584c8077b1df483db087362638a87e9d866addd98e048fb91066e2. 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/QMDA62492523.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x97c747d846a30bc7d56e2defb59c3d1cf1d8f8bb7d055b15657f1dc6dcf5602c. 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/QMDA62492517.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4db86274a11db473eccb4e101bdd4fe50f2d7390727cba1c954ea537e1a86c27. 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/QMDA62492504.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x38c8d193aaa959371599934201b38dc8ee980aada0d48b0cb96497240d493ed4. 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/QMDA62492476.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x68a5fc42d7fd75227da9fdf8651c6c3c49be17a21b6d1ce075e9d9edc2378cf0. 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/QMDA62492522.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x11e873f6119ded094ca615351d44c2358afdc6a0c880c31205d7469caec2b856. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/QMDA62492472.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa1bb0e7197e0a144dcc8713983cbbd9c6bf8333cf67aa83c3453c36ae695ff90. 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/QMDA62492515.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1cc2daa9a51461a3e93c782c42605a9d1b755c9cc4e548dc7f4f371edacbcdac. 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/DELV42300988.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e5f47339daf81bc2b85e3023f5c7817f82b4320c0d7a00e1d6b770cdabd0fa5. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/DELV42300990.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc1e52aad89073e81d9de8a2a20bfd45a65ba8812f0f1dbc7a62f02e3db9eb3cd. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/DELV42300991.