thumb|Kairos relief, copy of Lysippos, in Trogir (Croatia) thumb|Kairos as portrayed in a 16th-century fresco by Francesco Salviati Kairos () is an ancient Greek word meaning 'the exact or critical t
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 0x4280515fba35552a399884f2894df38b4ddfeb41d69cdbc99855e3dd74831b82. 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/d7efa73b-52e5-48a6-8c2e-11d7ac1189d1.json and https://artists.proofprofile.net/proofs/artist/d7efa73b-52e5-48a6-8c2e-11d7ac1189d1.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 0x03110537606e66d01b8c3dac97e4156ac21ee7c1f8983d9c9e63f39c2ea0654a. Chain 2 (Bitcoin): anchored in block 959137 (2026-07-22T16:56:03Z), 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/QM3DF2251467.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc965a5bc184bfc322e88f6a4efaa84c77107c90b85cd04b39fdf18dcdf9e4582. 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/QM3DF2436937.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe29a9a457696ef3ac484a89c9503c20423f9c7b2b647aa7f73d6b3a5a7451206. 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/QMANG2415028.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x26d76c50a3f545ea6fc122ad3102d75e1c83a54b8dc888eadd5ada472edd237a. 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/USANG2435993.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0ac7b8fb98d3f6452388c9fe6e8290def08c28e6a8b4aa1eb788f2b1a9f20516. 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/US3DF2448964.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59658f4165ff74ef2e476d442b215b48527dddbe3f1e71922637769e56d37e96. 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/QMANG2410407.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x357f15511ca5b55fee73a1e8c56961310fcd6b223bb4896fbd68929968470311. 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/QMANG2485370.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcc3526cdbbc49b4582f50c5879422ef109d2595f46384004fc62d0436b747709. 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/QM3DF2474825.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeab043875c675afbe6bd0ed9557c396a2677a220baf2cbd8142f4ca06aaf5730. 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/UKZGC2309381.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ae616bdaeb99de6acee3cfb216aba7b7441bcac34d33276789d464ed785c621. 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/TLREW2225351.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x98d5a6427c1dcc8c2e1036797a92ccd1da45d4b3f3e6a4cec4fe3a136f1e4ae9. 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/TLREW2225352.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7909a15fd4ad8fcad287f5802649aa2949074e75702ba57b473c41384c74ad9a. 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/TLREW2225353.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x16cbc621e2141c059b1575ac412ace98dd1a12a676223b0cf7b4eb8c214c4a1d. 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/TLREW2223019.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x38f38efd85095a72c78a692c16464d24c67131adf7cab4db8acf08571f046940. 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/TLREW2225354.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa4130eb6cf21984542a53a8fc03d0e60d6ec8e8815cf74d2e14765710918b83d. Chain 2 (Bitcoin): anchored in block 959137 (2026-07-22T14:03:35Z), 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/TLREW2225355.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x029bbbcafcbd291a71f8dfdd589c7e07ef9b3ab55e7f697c8273ce564f92d8c5. 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/TLREW2225356.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe3af1bebde13fd29f32a5da39e8cf6dae3532b016cd2b3eba2e0e7dedd4f8f68. 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/TLREW2225357.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe2815d4596b5e50a898c2656ea51aa3f1fdd424ef5361f2c889bb6f7b2fed1eb. 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/QMBZ92264172.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x94f8f0d185aebe0abeb591e5ae380fb7bec692875571370c4dd320f5a34f7910. 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/QMBZ92264173.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb963214dc96f8e41bec2ad019e494bf8d0bfd2f1e1e84e68ed562aa4d6655e87. 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/QMBZ92264174.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x12113946969ae68c74619f999c445d2add5a17d64500ba418710851950c33d34. 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/QMBZ92264175.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa1554a68455ae094cade4eb07b56ea3c9e7133e7134b983930791247735ebf07. 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/QMBZ92264176.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf7ae017edd6ccf3913ecdc55b9f5969bf73df496900835a8e1e9b3bab2f182dc. 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/QMBZ92264177.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2b8ff6b15fc0700b08e50f2c6d318d18b820aaeb4cc9c7ad2712403629fe7dbe. 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/QMBZ92264178.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf7b88a2c6b6cfe97919a2bc49bbacb6ca2d8da710f4ea7668913b041f40a3c87. 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/QMBZ92264179.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3936bb7ee674311753ab1189337132ec9e3a7ba0c0932b0dd3cb4166ae2eab38. 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/GXESV2402487.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf3a9b54c0c3f541d189293404e01de0628e8feda7b65cc4379d30fbebd933eea. 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/QMANG2203804.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb02ba29d8e179f94b989d563843198f17a0c76795059d568f69e6dee90da1140. 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/QM3DF2282272.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb5ef299b9bfdd32ff1b08f576e37037ae9866f1ac042975c81134be60acce10e. 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/NLX9G2300296.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3aafc578ac18a531d28e8a51b4cf153cd492a1d1d54e0e33306138bfb0c47797. 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/QMDA72295239.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6eab4fa0b4ecfdd74b7bc119e5198ae9b7ef280b5179c573ddc4ca9ce432be0b. 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/QMDA72295240.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc33c5166a38bb57cb4325dda5d140c861429eb715b8b6df5e7460756542a8a8c. 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/QMDA72295241.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9df2ae9bfd8b7728139a1f31cce90981b8e0f17d80a23ffa80934f69dda66fa7. 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/QMDA72295243.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x36a972d256c603fe5695e34fc452276a2b31b03e40ddcadd2b57e5c022436895. 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/QMDA72295244.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa8d5e9e0fe27fedd357653c3c282a84902fa1c7fbdb4129494332d9bdc649117. 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/US3DF2299091.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1eeebc67a91471e2caa81d66037e12bb4dc1d885eb9f2fc01346ca5cf6fae0b6. 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/US3DF2298854.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdd4057fc126dfaa4bc9c4d3d1534b75f6559f7d2a30d965714a4a17a778c9ff9. Chain 2 (Bitcoin): anchored in block 954130 (2026-06-17T19:07:14Z), 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/BCD4N2100095.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe22bdd99c4a0f7ed48a856d846d340543b3c87580d4621d344acc7dc02357ae1. 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/BCD4N2100096.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe7026e42ff922b6d8b9e1b490d7d6c6027ee18bbe5dfda16bce1d47ec067879f. 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/BCD4N2100097.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x52b0904f9760ea59f8671a56ec67098bd3c659b94e216d77b1ae746514ab52c3. 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/BCD4N2100098.