The Night Café () is an oil painting created by Dutch artist Vincent van Gogh in September 1888 in Arles. Its title is inscribed lower right beneath the signature. The painting is owned by Yale Univer
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 0x2377657bd57fba99d2ccb613efe8e2dc13341d5879bdc3485ea15e1aebb1d8fb. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/dc4a5f23-263e-4a56-9504-c235106a1ee5.json and https://artists.proofprofile.net/proofs/artist/dc4a5f23-263e-4a56-9504-c235106a1ee5.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 0xa78ffa09921bf3a41baad253d14c72f40e939c4327e88d219f223c37963bd31a. 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/GBKPL1947920.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x045395d9f0a262c08cda6a6084fc6aebc9880c431e958518ce0321848c82bdbf. 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/GBKPL1947905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x13b4ec78cd172bba68ce03dbcd0b3a7a350176e5d16e22472fdb043217bbc9f6. 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/GBKPL1947917.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc456dc0eb902ac537304f7ab7fe08f25fd6550c77607f7a2190f95cf59695b01. 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/GBKPL1947911.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1753aa09a811be2c3f244d7af631148c08e4097039ee94cd8051e57322d96693. 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/GBKPL1947919.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x237808e3203f1f0b293a8ca23360f5038ddd532a59c3a747a13c8356d70994e6. 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/GBKPL1947918.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbba298d37343ac633956832764603f92d795eefa3b6198260692cdcc6d4d8a02. 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/GBKPL1947914.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe3e6e7bbb081f0fa8f21c992c7ece58e2b4675210bf787c6b52d9f483decd7e7. 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/GBKPL1947906.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0f4de50cbef9ea4e790a7ede3e214fb577a48e76a9a6d7db7c3fe0ec254d8fec. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/GBKPL1832749.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x75aa31508582959d5fe385674ccfb9fa46f8d7621a33cca1eea31d6b55f27190. 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/GBKPL1947907.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaa6b87131ebc31c5f54dfb39dcc1c4334ebafb1231d4b8e733ae67305cda088c. 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/GBKPL1947921.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x105059ad6931f599cadf677fdf3ecc8bdd0d411aeae98068992a17928476480d. 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/GBKPL1947908.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0b5d7533f05170daccb2954106c436397bbe9f205511922f53a5130c5ae306e0. 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/GBKPL1947909.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8f4449eda8c815cc05c6d217d7f9c09b65c34d5fc5499e3ee18f7e2aac233a62. 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/GBKPL1947916.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x051a91ff10045c4a1d8a9599e6167655b753ed4252cc5529e4939c9dee4e5b6d. 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/GBKPL1947910.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5f773fbf80b38f48f7807cf3e0ac04e8a368bab73b7b2f6060b4769ea7411dec. 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/GBKPL1947913.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe1e2c4e16b3f1d3162521aba7440b86b8f8b95b00c2dc20c63f1e03ea117dc41. 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/GBKPL1947915.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb02b34dcd265499225a4988938af7bedd2f8030b19b0c4ce7ea47bbf43979b4b. 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/GBKPL1947912.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf4a6b1ec9b361140d9d24e4b230708e413df8f5617acd8ec883c66536c50a834. 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/GBKPL2142674.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaf07cc038e01cf6a7c5463f2596bae395437cc324564eca33190940c77f4418a. 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/GBKPL2142675.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0adab6d5221d0fe78790e91af8d80dca0c54c97920fbb7cea582babaa38fee92. 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/GBKPL2142676.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x05a46ad4bb71bdaf8cc490305600f09401b5cbd2673e535d64824bf8afd7cb9d. 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/GBKPL2142677.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf4a6b1ec9b361140d9d24e4b230708e413df8f5617acd8ec883c66536c50a834. 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/GBKPL2142674.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5f773fbf80b38f48f7807cf3e0ac04e8a368bab73b7b2f6060b4769ea7411dec. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/GBKPL1947913.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe1e2c4e16b3f1d3162521aba7440b86b8f8b95b00c2dc20c63f1e03ea117dc41. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/GBKPL1947915.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x045395d9f0a262c08cda6a6084fc6aebc9880c431e958518ce0321848c82bdbf. 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/GBKPL1947905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc456dc0eb902ac537304f7ab7fe08f25fd6550c77607f7a2190f95cf59695b01. 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/GBKPL1947911.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbba298d37343ac633956832764603f92d795eefa3b6198260692cdcc6d4d8a02. 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/GBKPL1947914.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0f4de50cbef9ea4e790a7ede3e214fb577a48e76a9a6d7db7c3fe0ec254d8fec. 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/GBKPL1832749.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc44dadd0b23a9e7e623e21054dcd62353eaa6eb493ef913dc1629a3733af0f13. 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/GBKPL1782941.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x74b3da84090bacf7f313d43c59c04cfaa119a585b604073abe3aedb9cd98f36f. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/GBKPL1791633.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x24299bfbb9991b369adef40daf5561e8c2c6da9ce96115d4c5b596a1d9a87f2a. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/GBKPL1811590.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x360c17cc2f549ade5b9596b513474560fc3ade9aca3d02ac47ab83b3be14bbfe. 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/GBKPL1811591.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x30f9e2353e626191b40a81981677a8ae17e9e4059c70c0ccc9e6765c4e5d61bc. 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/GBKPL1670555.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xba7d5d9ddcd6de89860d40cb15606567e509df3fc784c6110dff5fd63be2ac1c. 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/GBKPL1671443.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x256c1c70d7fd945273b0af33c9d222ac74520e306f28eef956dca8f0b3eae290. 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/GBKPL1777141.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x98900189a6eec2c7631da5f1736e215bcb2ac797668a831aa7ab0344b526e35c. 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/GBKPL1777905.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd3813232fefae1bf3a9d2d5a1f934709eff67fda4ead11e63b93f12b534b56cc. 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/GBKPL1664133.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5ef652f21081d990295b7dc870927fe22fe65c8f634cf9ccb889e85cb1c2262a. 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/GBKPL1664134.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1382f762c2888dc5d28d25a546bda6ae56f10a09641e535b0cbd7d8081f509e5. 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/GBKPL1561623.