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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 0xe363340e54f0ceac063fb89c148c059b62e751276fd8ba5741791a4f919c0487. 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/5a6cb9d7-61bd-40ee-af12-91f90a78e7c8.json and https://artists.proofprofile.net/proofs/artist/5a6cb9d7-61bd-40ee-af12-91f90a78e7c8.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 0x2a13a345006da1cb384e21b03bdcb41df59cd23a46be4d67a00759cca7add578. 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/QM24S2402236.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x98132daa12e74fc3da79187499f02252863d5732cb4adb120549e7007491ba54. 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/QM24S2402235.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf16845789e5ed5922d709581220eed84ba0046e3c3d40089290629dc3707754a. 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/QM24S2402234.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x339bf23260e526bbaf7b004ce8fd5a5230ab63462e6b1bcb723dd319a318cf37. 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/QM24S2402233.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1321eac7b563e797115bfb9e09633d2a08ac791e87cb9d0d905c8adcb9185c0e. 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/QM24S2402232.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4159d7cabf8c2a8a469e6be73337c86f41e2c32caa07ca34167b4836415870a9. 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/QM24S2401858.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4159d7cabf8c2a8a469e6be73337c86f41e2c32caa07ca34167b4836415870a9. 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/QM24S2401858.
Easy to Love (Live) - The Sweater Sessions
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x858baa1e08b93a228b816056b183fcd8db318916cd3d9981cb919246fb15fe3e. 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/QM24S2400327.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5ef05b7c5f5bfa6f630e1048ccc06b7984b9041c795438b5b1074ea0cae6ccbd. 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/QM24S2400326.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c6f54173c5285b23e69fe222a0ac6ccd8aabd685ce9ad20ffa9a9bea273a952. 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/QM24S2400325.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2bd94689f79f4b81ea84e8c0418bb2cac5a0a487e082e2a2ad50b956854c1ea5. 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/QZTB32332828.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2827b38adb0f8fd4bd99702cd7794d6e22f63e747c5995ecda5c1706f300a691. 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/QZTAX2318535.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2827b38adb0f8fd4bd99702cd7794d6e22f63e747c5995ecda5c1706f300a691. 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/QZTAX2318535.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe1469f0c4547b47fda2310512c4288a2fb6dc161d2d686f3e7f844f6d571ac29. 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/QZTAY2235987.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x425d87174b67279a9d5f1fe5c421588ef4e798eaf05f54e94fb3dc8bebd5adf5. 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/QZNWW2216191.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb22ccafa4f8b7f4023fbd7a9a6ae9a2295b58b6ee3c5b600233322782604a4f2. 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/QZRP42298033.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb22ccafa4f8b7f4023fbd7a9a6ae9a2295b58b6ee3c5b600233322782604a4f2. 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/QZRP42298033.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbe9f9215d33cea680eccc9073d1da45d8c86c9ebc7f7ee23c76323c361c2f172. 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/QZFYZ2124086.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe36ab1daf06d329ebb9380c6d7bb3d4dbb2db359bb892f7cbd058361d39dface. 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/QZHNA1926184.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xae14bdab51c4be191ef97bff398cc8ce319dd47c3bd14b7a2186ac3d4031b478. 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/QZDA71908707.