thumb|Renato Cioni (photo with 1960 dedication) Renato Cioni (15 April 1929 – 4 March 2014) was an Italian operatic lyric tenor, particularly associated with the Italian repertory. Born in Portoferr
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 0x5af48ec1cbda6bff3db448880416bbd198e8ef7c332bd33026a91b2d8077888f. Chain 2 (Bitcoin): anchored in block 954046 (2026-06-17T04:53:03Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/407b3e77-8700-4fa1-9e42-e9ee0c175779.json and https://artists.proofprofile.net/proofs/artist/407b3e77-8700-4fa1-9e42-e9ee0c175779.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
La traviata, Act II: Act II Scene 1: Un di, quando le veneri (Germont)
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 0x9c8ffd58647aa19c5bfe3e6ef58dd104e30d99491e407ee364c5e9e0c20ed6a4. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/ITX921001467 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x75264097f4afdfad4a71f15ed5c8d684b9c3213c6205ece3a8e698928dd1b08e. Chain 2 (Bitcoin): anchored in block 960216 (2026-07-30T06:39:12Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/US89R0699354 — a six-check JSON result.
Verdi: La Traviata: Un di, felice, eterea - Act One
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3c633a87fc3c2e493198161a174ca4427abe15d333deb3b71b6c7ee894c9ed68. 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/US89R0699358 — a six-check JSON result.
Verdi: La Traviata: Libiamo ne'lieti calici - Act One
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x52138e2631eb3a9726d0af87d095496bd942a93d1509531708cc00ebfaf732cb. Chain 2 (Bitcoin): anchored in block 960264 (2026-07-30T14:36:16Z), 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/US89R0699356 — a six-check JSON result.
Verdi: La Traviata: Dell'invito trascorsa e gia l'ora? - Act One
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x901e27d1d62656ba03fe9e5d775b8e8c07dc932f6610e864d44fb476f1fa1467. 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/US89R0699355 — a six-check JSON result.
Verdi: La Traviata: Addio del passato - Act Three
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xba418c7eae09ee032586d0b529fd5a1d0ec68621fd817c74cd434caa98d4924b. 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/US89R0699390 — a six-check JSON result.