thumb|A cardioidthumb|right|200px|The caustic appearing on the surface of this cup of coffee is a cardioid. In geometry, a cardioid () is a plane curve traced by a point on the perimeter of a circle
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 0x9cc483207064eacee24477075b2251133c669c7a602a716d9e7bc345b6cded7b. Chain 2 (Bitcoin): anchored in block 954174 (2026-06-18T03:01:36Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7d7d0927-da91-4bf9-89df-e3ff08464851.json and https://artists.proofprofile.net/proofs/artist/7d7d0927-da91-4bf9-89df-e3ff08464851.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 0x78837c9c90a21dc59c78bf09b17e5a53d9653b2a99b0c0bfb2f8cedf52c8284c. 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/QZFYW2179159.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x84e7680e600396ad0fdfd81b4d5654b3e5624946cc09fc206b38e6f2df9f74f1. 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/QZFYW2180277.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfe26c91c7f1db6a39ba78d43929a189fefc460473e2a6bae403325eda7626301. 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/QZFYW2180279.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbe1034726c496acc61c9ac614c9e69ffebe461608716802ae2994a3cb2c31a0a. Chain 2 (Bitcoin): anchored in block 960494 (2026-08-01T01:44:32Z), 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/QZFYW2180280.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2fbb764241aa23b652b0b42a1c2d64f65f21558ad358a2f0d6f8ca8931efc974. 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/USCGJ1728510.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x602d0465ba5f10ade98ace2d381f90c8c6380a3aaf6cfc2c8e66520d01bf58e4. Chain 2 (Bitcoin): anchored in block 960427 (2026-07-31T15:59:18Z), 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/USCGJ1728504.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc7fd5a752b109cd4e32b0272ba92f8d37299653aa6d17050fdeda65789ac7fd9. Chain 2 (Bitcoin): anchored in block 960455 (2026-07-31T19:53:13Z), 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/USCGJ1728505.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xedc13cbc363f5341dafdb671275e3249823aea4bd7c925ca3544bb704e45d399. Chain 2 (Bitcoin): anchored in block 960403 (2026-07-31T13:04:34Z), 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/USCGJ1728506.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f4a7a51ada09f3fd85c07777d7c041376304625b27cbf528f0e000aeac4b19a. Chain 2 (Bitcoin): anchored in block 960327 (2026-07-31T00:26:26Z), 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/USCGJ1728507.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x241b3eccdf799393f2d2caa24efbd84af79e4d54a149717380a55bf4bed72994. Chain 2 (Bitcoin): anchored in block 960435 (2026-07-31T16:33:26Z), 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/USCGJ1728508.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xae1d48649c59139f959b0ab05202584efe1da2a2235d2660c5f30de81556626b. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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/USCGJ1728509.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf2d7790b033be5be5095b7fe53912f0525329914fe2ae00115ef26400aee3f63. Chain 2 (Bitcoin): anchored in block 960302 (2026-07-30T20:09:33Z), 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/USCGJ1728511.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6cd23f3c464768d037d1f5de487f6722c7fca514a1f136df315f698ee9a935f3. 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/QZFYZ2251214.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa6c94d9714903cad4b2ca299d87424db3c42140e88f02cfdf54f41a28e9cc1be. 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/QZHNC2021139.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0748200007d467ccf3bcebce8c30f53f2e3b3691ce4bdacd0e28e52b99136ee3. 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/QZK6F2018244.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x420a677049afa2490fc991babe98f713ac6e911e22d2cc1c1c710a714d4516b5. Chain 2 (Bitcoin): anchored in block 960389 (2026-07-31T10:20:10Z), 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/QZFYX2003737.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x92ffb385b68250d0588971c5c3d2939032aee2163c74201f39f0b8d42001ab9e. Chain 2 (Bitcoin): anchored in block 960348 (2026-07-31T05:17:02Z), 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/QZFZ72009789.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3ea6367389c5ef1ae8dd8a51e70c2b4841bce8f0772ddd6011d4ada60ea01237. 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/USKRS2273301.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb1d35722b8ea5f89f328725775d2be832d53b1f630886e670899e7f4eee1a2e6. 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/USKRS2273303.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x78972386313da91e258f2359dde9e167bee6a1cfab2e1d085ee94334b3d2f546. Chain 2 (Bitcoin): anchored in block 956351 (2026-07-02T11:38:34Z), 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/USKRS2273304.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0107941e040fb27ff280bbcbfad35407b6c9ba437edff9a1b15058096efedc36. 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/USKRS2273305.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x147105c56e5f327bde8b041e544e37b92afb25817798b9c1055dd754aa18e9fc. Chain 2 (Bitcoin): anchored in block 957061 (2026-07-07T16:07:00Z), 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/USKRS2273306.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7d71c5f753cbaa33611c56855c1584e5112e4641cbb494445420e3f22cef878f. Chain 2 (Bitcoin): anchored in block 956894 (2026-07-06T07:53:57Z), 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/USKRS2273307.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd206eed804fb68ed84c791ec6605111d58118bd40594134365de4312f177a505. 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/USKRS2273308.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe929cb1afb5c6ada80d5cb790cbc3b682d0d0c3a2d48929cab4ea8440f73f805. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/USKRS2273309.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4218eb809924a24b23379522daefdd12af9f61d8d2ac19a928599d193835bb4f. 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/USKRS2273310.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e947bf5e9d37ec7ffde5bd4ff10d0586ce7e82ac223ee8f8e29fd150aafc785. 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/USKRS2273311.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf92d0cb9dcfa9bebeaf6bf8f46efd13aad97554c58f1f80867d5e4f9f0a7117. 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/USKRS2273313.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb94e788b162e61e274fd933b78bfb5369771e7678c84fdcc771b0e4fa5d95433. 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/USKRS2273315.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x43053021fa3745fa0cd0d5727738423bd8abab850e563451a735338dac7d1b10. 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/USKRS2273316.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a86230bf3b6cbbff1f57e7cad845be2d11182ba5f3c0eb5e6b2fbcd83c2aba5. 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/USKRS2273317.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4ffdb47032d66c4274450cd0e15e9e5a71bb2a39031e444497c13598f4cf125c. 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/USKRS2273318.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4612acc5e8fe2331940ee0bd35b4f03967da638d07c19e5bad4e65f4eac672ca. 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/USKRS2273319.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xffbe55c4ddd670a64bf3f05301895eb6b9ac14f71eaa6918e8e18074991097ae. Chain 2 (Bitcoin): anchored in block 960144 (2026-07-29T21:09:47Z), 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/USKRS2273312.