John Leventhal (born December 18, 1952) is an American musician, producer, songwriter, and recording engineer who has produced albums for William Bell, The Blind Boys of Alabama, Michelle Branch, Rosa
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 0xcc7a5d4b1c979194764143c1f8f42c341163678fcbd3bdb0767afd3e75f4bda3. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8b6961d8-f9a2-44ff-bd09-5d69ab156354.json and https://artists.proofprofile.net/proofs/artist/8b6961d8-f9a2-44ff-bd09-5d69ab156354.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
That's All I Know About Arkansas / JL's Hymn, No. 2
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 0x80d675ded536602a1502694e652ffc040f875f53952dfb0f6110e420474c398c. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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/QMFME2359132.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1d748b8bd9bcec0375c91a54461544449684b40e4df82a0bd388558664012d7e. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/QMFME2359135.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x050400492a739f1ee0d087597c46eeb936e0951763e05aba1358905562b14752. Chain 2 (Bitcoin): anchored in block 958690 (2026-07-19T07:14:39Z), 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/QMFME2359139.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x274b12c840de5c4a751a2d18f436e7164907d7e399ea80beac0adaaac7dd0b52. Chain 2 (Bitcoin): anchored in block 958544 (2026-07-18T12:14:37Z), 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/QMFME2359144.
Woody Guthrie: At 100! (Live At The Kennedy Center)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x224e71b75c09f36250b80901a3c9f5255a3d81b49e37ba0d10768e0330525986. 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/USQX91301083.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb2a74a0083cfa215d52574f2776dd3e18601e0bee9b02f97ed169e6b4fe207dc. 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/USUG12003908.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6dd018d835b9b567e828a08e6636a5c5ecd617106eab9f889216feeead436701. 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/USUG12003907.
For the Love of Harry: Everybody Sings Nilsson
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaf9ce5dd24b8b28af422ac16f7f06815bae2b6eaac5e04c77b0b1982770c8613. 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/USMU10820829.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6dd018d835b9b567e828a08e6636a5c5ecd617106eab9f889216feeead436701. 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/USUG12003907.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9d5e09254e34ab2c2c0cbe26f54fb1048604dc9c95e441b4b539e0fd37f65003. 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/DEQ831200001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x056f076c55c53e0f0a20f0c3dc8a29eef1ac7890adff009b78607ffea51b99de. Chain 2 (Bitcoin): anchored in block 957055 (2026-07-07T15:12:44Z), 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/DEQ831200003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdf3bfb4efef155629835ee94ff7b5ec35e270ae93590fc18de6ef7a7853de663. Chain 2 (Bitcoin): anchored in block 960177 (2026-07-30T00:21:01Z), 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/QZMP62370004.
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