Eri Klas (7 June 1939 – 26 February 2016) was an Estonian conductor. He conducted or served as artistic director for the Estonian National Opera, the Finnish National Opera, the Danish Symphony Orches
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 0x1b47c05636ac7b2133b122b3701efb81e72435da5eb3a6d9a17f658cc75b280c. Chain 2 (Bitcoin): anchored in block 953777 (2026-06-15T11:52:51Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d219b4d7-38f6-4441-bee6-7733a9e9f6eb.json and https://artists.proofprofile.net/proofs/artist/d219b4d7-38f6-4441-bee6-7733a9e9f6eb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Opera Arias (Baritone): Hakala, Tommi - Verdi, G. / Wagner, R. / Leoncavallo, R. / Puccini, G. / Giordano, U. / Gounod, C.F. / Mozart, W.A.
Englund, E.: Symphonies Nos. 4 and 5 / The Great Wall of China Suite
Englund, E.: Cello Concerto / Symphony No. 6
Don Giovanni, K. 527: Don Giovanni, a cenar teco
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 0x0afef0235eb8f5eeae03071e5df1faebb1b83d3c79f57a961b3f5c394d06614b. 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/USB8U1612272.
Siv Wennberg: A Great Primadonna, Vol. 4 "Arias, Duettes and Scenes"
Three Degrees of Freedom. MUSIC > CINEMA > USSR. (1) Alfred Schnittke
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb930915d3fb3532199eaa6713d501b630e5473272d417420e5e86f4059870fa0. 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/ZZOPM2118960.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7cd29c19e8e5c3bd5b4673aacfbd5bb8d0d80d338a329e3913c8ad5db9f55588. Chain 2 (Bitcoin): anchored in block 960236 (2026-07-30T09:37:10Z), 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/ZZOPM2118961.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdd7864bc79ad9e8206171b7ff0aefd57dd9ce293e9b52726f1ae103b4b592112. Chain 2 (Bitcoin): anchored in block 960337 (2026-07-31T02:51:48Z), 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/ZZOPM2118957.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x318e20bddb28ffa16ddcb286e5b6940b5db1c6a38587b82b33522678c8bc84ac. Chain 2 (Bitcoin): anchored in block 960441 (2026-07-31T17:29:52Z), 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/ZZOPM2118956.