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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 0x399ee9c490c51148810828bfeb21347a85bf1847e00cccb576e6ab85100ac08e. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/68e0014d-c93b-4c6c-93f6-9187cc2e3ba3.json and https://artists.proofprofile.net/proofs/artist/68e0014d-c93b-4c6c-93f6-9187cc2e3ba3.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 0x4ff3b502ccedd0b1c8406936c6ede4b9eecb3b79b64f83ecf208835a18f2200f. 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/QZDA71935851.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe50e68803aefa624ef9e16f20304140f5f6d62ef8c0ad52ffba31b2d8eb6a0e9. 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/QZDA71935852.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe134175b84608d9aa571abc8fcc0d0cee9af666a34256af0d7f02d2220fe786e. 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/QZDA71935853.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa6465db5002b28b8dfa47563d88a3d93b643f366b930fc3ba1f5d32905a82235. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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/QZDA71935854.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9558bb473f9c7b3043f2acdedea63014ec158b4ea51cdfca1c44719f53236267. Chain 2 (Bitcoin): anchored in block 960497 (2026-08-01T02:22:04Z), 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/QZDA71935855.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7d1b6a72c14ebdf26c74d30001767bade41ce07be2ec8d071ca311281e6ad8fb. 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/QZDA71935856.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x50cab251667da109702c861b0315639abf773a6435d1f57ae8f83b45b5860db6. Chain 2 (Bitcoin): anchored in block 960254 (2026-07-30T12:06:10Z), 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/QZDA71935857.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1442890f59c1e18bd7b015b5aa19dbc0ddb37a3f3fadf8aa60fb6ee80809f5d9. Chain 2 (Bitcoin): anchored in block 960506 (2026-08-01T03:50:58Z), 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/QZDA71935858.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x400edad0eded78e0f38c72fea622af96d69616a34550d59aba33c84605cfb329. 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/QZDA71935860.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x918cb27fe62c79ef444aaf59f2736f7fd3db43f2b00c1444587024232dd6e4f0. 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/US7VG1788237.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaf5110c642aa2d20110a48b83905e8183b9b7649ff5a0dc0d1a9f24e223f0fa9. Chain 2 (Bitcoin): anchored in block 960203 (2026-07-30T03:35:13Z), 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/QZDA71935151.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6a942d3381362ca6e5b6a0c1a07eff54f06a9b84334968fcb48fb1f63b667e92. Chain 2 (Bitcoin): anchored in block 960506 (2026-08-01T03:50:58Z), 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/QZDA71935152.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x368612e1586a666faff47d8c3e794df9de2ab7e5e9d2777fca481630e5e4f9f4. Chain 2 (Bitcoin): anchored in block 960500 (2026-08-01T03:13:03Z), 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/QZDA71935154.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6bc37364d87f3e90826156ec425d1f0783f9fc4875a4871a3528b00ef744a509. Chain 2 (Bitcoin): anchored in block 960500 (2026-08-01T03:13:03Z), 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/QZDA71935155.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x65f6203f1d87ae750418aae92adea87fec7e6cd4a72fa54b1c2dbb37986b41e4. 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/QZDA71935156.