Josef Leimberg (born November 29, 1972) is a producer, lyricist, and trumpet player from Los Angeles. He contributed to Kendrick Lamar's Grammy Award-winning album, To Pimp a Butterfly and Snoop Dogg'
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 0xd1fe96e1ec1d2d0962cb7d3d3d24503748e0ab1f78ea19d333e51bcf26350bb1. Chain 2 (Bitcoin): anchored in block 953758 (2026-06-15T07:48:25Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b217038c-595c-42a8-8794-3298e66d11f0.json and https://artists.proofprofile.net/proofs/artist/b217038c-595c-42a8-8794-3298e66d11f0.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 0x3e0290b1890e892e0a32eb24a9a7f9d0da501536a29708cafff756d7b8199817. Chain 2 (Bitcoin): anchored in block 956349 (2026-07-02T11:34:59Z), 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/US25X1089921.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x39c20f4902a9606e0fb4bb6b781f68411b7ba625b28cb4f9d210c9563d931356. 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/US25X1089923.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdea9b179166143984252faff83b0c1740009de3f23521fe62c017b168dd392be. 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/US25X1089924.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x77b0760da27a5b1aed6e44bb4fed0a3c842dce895bcd80d7f4b2e25b32fe9439. 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/US25X1089925.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x49c877824efd7705ec5a2efa38d896758099f3c707537d6c9ddbda88f30968e5. 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/US25X1089926.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x51caeff1976b263d3b3c4557e336f4c9ceffc8788297fdde965641fcbf8946d1. 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/US25X1089929.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd47bafc4b635dce4bb5eb8aad904729af55fff4df5205c0e329b41967766bb98. Chain 2 (Bitcoin): anchored in block 956476 (2026-07-03T09:04:44Z), 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/US25X2500064.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2f0171b7d4062b1e99d7e36bf9f5c3ed6c338848552b40f1fb9050aa8e5c0da2. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/US25X2500059.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x33d764717013d75b366ac48a40189bcaadfc16fb488557805bc5df4d746b961b. Chain 2 (Bitcoin): anchored in block 958689 (2026-07-19T07:11:11Z), 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/US25X2500063.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd47bafc4b635dce4bb5eb8aad904729af55fff4df5205c0e329b41967766bb98. Chain 2 (Bitcoin): anchored in block 956861 (2026-07-06T01:57:57Z), 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/US25X2500064.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7118469f32a7c89a17814a387b4f35d679f810dba223e3f865cba175d54058cf. Chain 2 (Bitcoin): anchored in block 958876 (2026-07-20T12:15:48Z), 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/US25X2500065.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf2e08b38b84e5338663894883a1307f5806be5d7e36ea09aef913d4d18e7ad8d. Chain 2 (Bitcoin): anchored in block 957774 (2026-07-12T23:51:20Z), 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/US25X2500066.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4ace7966d00db6b1cd21784dd1c4b43e85a0b3fdb6c698580a3dbe3e9506a484. 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/US25X2500067.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf3455b0b1d26c7fc4dfde38f17811e237f7622479f76b16a8b58c58a1dba49b7. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/FR59R2168430.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9d469409e3dbfc9ad86365ca62f0a6be5e697a2fe2b37a506aac9dca844bd82f. 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/TCJPG1860665.
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