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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 0x38d97fd494decf7ba5f43e1a915d6016e268b937dcbf3ec839782f947fdc368b. Chain 2 (Bitcoin): anchored in block 954728 (2026-06-21T18:08:38Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/f95f1daa-4e81-4266-9638-5bf5f788c644.json and https://artists.proofprofile.net/proofs/artist/f95f1daa-4e81-4266-9638-5bf5f788c644.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 0x8a49f78ddd32ce318ee5eafb44a65c22fd83e3a733ecbe68ed21d5a0f685032e. Chain 2 (Bitcoin): anchored in block 960209 (2026-07-30T05:15:54Z), 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/QZRP42220601.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x66c55041b34cf474812ab699bb5d1cd137dac9e6b5f4132d45deeea008f198de. 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/QZNWQ2288508.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xac801b5c1d31fe95421bd073f1d6ae2505fecc37e272afe948e10153ace3621f. Chain 2 (Bitcoin): anchored in block 960503 (2026-08-01T03:41:24Z), 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/QZRP42220602.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc53e75e5e5378a298e5060105df893c3301d788a0c0678ae889d446dfa246710. 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/QZRP42220603.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x465c6585f1d20db50095bbafd7fff8d1b1a70da90e845c66218a45562ce0e4c7. 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/QZRP42220604.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x939fdfe3720068a0ed1426ef8972f002ea3e35b4a13564f313e4fe4172e83f52. 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/QZRP42220607.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc800d6bf397dddc92880cf6926b3dbb38474500ffc8975881eef02d7f4387a22. Chain 2 (Bitcoin): anchored in block 960321 (2026-07-30T22:27:30Z), 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/QZRP42220608.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x817c9765f9a5cd575e3f464fdd6707be030c8375dda517dbf3e660b4bfd2f5bb. Chain 2 (Bitcoin): anchored in block 960410 (2026-07-31T13:50:38Z), 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/QZHN62262484.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8819d1cd8f627ab57a1427fabb7acb2074eb24792b989cb3468f2c9fc31a10eb. 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/QZTBA2306074.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x60fed3a40a284a1d0a561d113076713fc5097dbc7f3ac8c573f9480f0e0c1c61. Chain 2 (Bitcoin): anchored in block 960459 (2026-07-31T20:22:46Z), 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/QZTBE2337933.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7e02d39b2995c835987010ee049802406dbab00693932746d3e48d06b090d017. 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/QZTBE2382276.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd6e29599888f23205989fad45b9d2e518f33cee44c25d4feb0e775fcad332597. 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/QZTBE2382277.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9915df72cb5ab17602e549b02f27b9d2daf7f51472959142dce1ea4a276d6cf8. 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/QZTBF2349945.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x60fed3a40a284a1d0a561d113076713fc5097dbc7f3ac8c573f9480f0e0c1c61. 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/QZTBE2337933.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8819d1cd8f627ab57a1427fabb7acb2074eb24792b989cb3468f2c9fc31a10eb. Chain 2 (Bitcoin): anchored in block 960236 (2026-07-30T09:37:10Z), 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/QZTBA2306074.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x817c9765f9a5cd575e3f464fdd6707be030c8375dda517dbf3e660b4bfd2f5bb. Chain 2 (Bitcoin): anchored in block 960381 (2026-07-31T09:50:11Z), 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/QZHN62262484.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa8c8652c2566ddd360a219fa1e562bb14c2d2cb7c6dd4f17294641e9cddaeddc. Chain 2 (Bitcoin): anchored in block 960247 (2026-07-30T10:42:33Z), 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/QZES72165178.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x28e323532326006dc5f480ebb7a733f3d240f1d3e059fa213efdc28b827abe2c. 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/QZES72165179.