thumb|right|Kurt Atterberg Kurt Magnus Atterberg (, 12 December 188715 February 1974) was a Swedish composer and civil engineer.Don Michael Randel, editor (1996). "Atterberg, Kurt", The Harvard Biogra
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 0x23c7a58d96c975ce910a454f34052ec122b352bc60f9d68ec7f14a555262ce3f. Chain 2 (Bitcoin): anchored in block 953605 (2026-06-14T07:39:50Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/11260d03-69b8-465d-abf9-0ae8bb757ecd.json and https://artists.proofprofile.net/proofs/artist/11260d03-69b8-465d-abf9-0ae8bb757ecd.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Kurt Atterberg: Concerto for Violin, Cello and Orchestra - Barocco - Sinfonia per archi
Barocco Suite No. 5 for Chamber Orchestra, Op. 23: IV. Pastorale e Gagliarda
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 0xaced375c6edb5d74e338fe44b16ee810747328a7eaa5d5397f22df3b6d27ed8e. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DKECA1983604 — a six-check JSON result.
Cello Concerto in C Minor, Op. 21: II. Adagio -
Atterberg: Cello Concerto / Brahms: String Sextet No. 2 (Arr. for String Orchestra)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d9adad3281f4be411ac663f77fd67e6ab8e96d5744d757282a4ca36fc7d3b81. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/SEAEP0604020 — a six-check JSON result.
Horn Concerto in A Major, Op. 28: II. Adagio
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8d4aa62da3a0237b6cd9b2e25a7af300ef7741e3eb1edfd1769c4b5cdfb6b88a. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/SEAED8776100 — a six-check JSON result.
Horn Concerto in A Major, Op. 28: I. Allegro pathetico
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa0188c915e6a453e4816533e02d718e610b7dd9b571422194f2622d93dc353ce. Chain 2 (Bitcoin): anchored in block 960463 (2026-07-31T20:42:35Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/SEAED8776090 — a six-check JSON result.