Erich Gruenberg (12 October 19247 August 2020) was an Austrian-born British violinist and teacher. Following studies in Israel, he was a principal violinist of major orchestras, including the Royal
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 0xc3b7db250eb8edf8e7d2856eddf7cee2df6e9b28cc8af654ff1308d3c391bee8. Chain 2 (Bitcoin): anchored in block 953768 (2026-06-15T09:30:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c0c7f682-78aa-40ab-892e-fb47e45b331e.json and https://artists.proofprofile.net/proofs/artist/c0c7f682-78aa-40ab-892e-fb47e45b331e.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 0x307269654c2d462dc173d54a7a597e468d9966d832a94299e9f2c2678d06894b. 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/GBF077211941.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf441a68b41f7d9403f07d3446b2a0c433c3195124751e2fe4efb9efdf6d2b040. 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/GBF077711540.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x821f208e0bd0250885ec33a10635926aa672e4663b7f3fbedc8961558d9505e8. 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/GBF077211942.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcce031ccd20683ced88585bd6cd8d4faf91350f5a27fcb5c9a05ef32a293e2ae. 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/GBF077211943.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e32f51ca3a24b4ca96ed14bf5239ebc192e6a31e2bf34b42dfc7c257f44efc1. 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/GBF077211944.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6eb09370c94f48146a54cdc29cfd383047edfb50bb74b4f918e07f16950be004. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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/GBF077211945.
Der Opernball. Overture: Im Chambre Separée
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ffa1c89cb845e4021cba7462916f2c2203b7e4d5c0b5bda2ccd3072f2cc17e0. Chain 2 (Bitcoin): anchored in block 960229 (2026-07-30T08:30:10Z), 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/GBF077211946.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x16cb3af1e13a69ad4be5b070c3ccc7922ab8882a0b8993698f44c1722406b82c. 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/GBF077213330.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8e04d099ee136ee3e69472b55e652469c38480ce753e14207a4ae86305a454b. 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/GBF077213340.
Much Ado About Nothing - Incidental Music - Concert Suite: Intermezzo (Garden Scene)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x949500f53573dfc2d2d667e27bf242f65957aec0f2e81d093645740b76801753. Chain 2 (Bitcoin): anchored in block 960175 (2026-07-30T00:16:15Z), 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/GBF077211690.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff1622bff95059036d767d1952705e718e5f75d7ac513189981de88597da2920. 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/GBF077714340.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x873e4f3248267460bd2d0605e2fbec5de756a8d9df379cae16b9848a3226056b. Chain 2 (Bitcoin): anchored in block 957020 (2026-07-07T09:18:01Z), 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/GBF077211700.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x121de56dfecae818219b59b923d9ab417873698cacb2972f9608d9aee36548a1. 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/GBF077211948.
Banks, Morgan & Fricker: Violin Concertos
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x006688b1dbb33c8703cd94c85b424f76d703dc854cf9372a7d44355753697f0b. 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/GBF076210991.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4ddeb2ddff240655f1217447098166cd5d3fc7ba91976ce9076c7970ca7a8b2e. 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/GBF076210992.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2ef4b617d6e55a70c386e17ff4b00959a95f24c736c0ea1d7e1a70d48bb329ee. 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/GBF076210995.
Swan Lake, Op. 20, TH.12 / Act 3: Pas de deux: Introduction (Moderato) - Variations I & II - Coda
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaf962a6a2b5d0fc61f384870c8325d28ef74788d3c9851fe05d0469ccb8d03cb. Chain 2 (Bitcoin): anchored in block 960370 (2026-07-31T08:38:45Z), 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/GBF076210996.
Pas de quatre - Arr. for Mme Markova by William McDermott
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdcf4ba1e62eaf03f5f443a1a32ca8eced49af1a2f79544c2823f5d3849a94d78. Chain 2 (Bitcoin): anchored in block 960160 (2026-07-29T22:48:59Z), 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/GBF076210998.