thumb|Amaia Zubiria Amaia Zubiria (born 1947) is a Spanish-Basque singer who was born in Usurbil in the Basque province of Gipuzkoa. She started singing with Txomin Artola with whom she formed the Hai
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 0xd8195861b4c5367d6a76d5f79e9ec12db77380ffff627bb8a4f6839833ea8407. Chain 2 (Bitcoin): anchored in block 953786 (2026-06-15T12:56:12Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/da90407e-4aa6-4bcd-9200-36d00aa01447.json and https://artists.proofprofile.net/proofs/artist/da90407e-4aa6-4bcd-9200-36d00aa01447.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 0xc54ec5c966cc4db716efface8e9655b3bedf1022dd806cdf5d8c2c5a20e554b8. Chain 2 (Bitcoin): anchored in block 956822 (2026-07-05T18:48:28Z), 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/ES5590800005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa0ef30457a745d44a32fc2a01c317716a274cabfcce58cc1c2409f2a2fa6954d. 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/ES5591500314.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x901507821712f8ae2d33989c7af5df10809d6669fc869204bff6aedf5ce42a4c. 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/ES5590600935.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xafffd8223473e3368e72e8b13358049646c6104d0bc954de9a49ef0aeaf5d7c9. Chain 2 (Bitcoin): anchored in block 960478 (2026-07-31T23:30:38Z), 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/ES5591500551.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3158985b7c7dd5348ab30dbb5651ce32f76ae4798d5679ab1dac435b670117b5. Chain 2 (Bitcoin): anchored in block 960478 (2026-07-31T23:30:38Z), 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/ES5591500553.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf7549e70862e932a4ee86f5cbbf39df3867396f805829f42878e34f2dabc8430. 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/ES5590600955.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd894678df01a538fbf2277b8cb066367837cc392766402678c3a5eaca3d741a2. 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/ES5590500035.