Pedro da Fonseca Caldeira Cabral (born 4 December 1950 in Lisbon, Portugal) is a Portuguese composer, published author and multi-instrumentalist who specializes in Mediaeval, Renaissance, Baroque and
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xda3ddc1c95f1b76a2100b428f06c51e51e4b1ada8c29ebab3cae92088ebd64ec. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/747e7201-fdce-4850-ac36-38a55d03a70f.json and https://artists.proofprofile.net/proofs/artist/747e7201-fdce-4850-ac36-38a55d03a70f.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x50c8dbb50d4779665fbe85cf5594c74af5ab42141d0d8c53512520942bb9073f. 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/PT6FK2300022.
Splendour of Guitars - Grandes Guitarristas
Fado - Special Edition World Heritage Vol.1
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcbe44fab34801eada52f7240756e6b6f8765313955ba18aa5706d183b3873e7f. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/PTOV10900003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd089f62f6c773c9d674aba0171a036b09907b3b6c67f4e8e8907e5f0144e7267. 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/PTOV10700003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb858750bf1450344fc1faf43815851a5645d44a2a698ab2ceac6384316664f37. Chain 2 (Bitcoin): anchored in block 957122 (2026-07-08T03:39:04Z), 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/PTOV19100030.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9766cdff12a06f16e4d99e0e3f43a95942857661365a9076310c0cb215c2cad9. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/NLRD52409932.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2e4c47535d5d9a1bc58509ece3e23f62109bad963b8eae1b3e2ba3460ac4d7a7. 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/PTOV10500094.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0e750bb14ad685a7e12805d1fc6ada94f81d8355436da5d6917bb1323cde2bd1. 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/PTOV10000037.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd1cdeddde49ad29a03b22b8b5d07619a1ff19fa1b4ab7b5936fc46b564893de1. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/PTOV19500030.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8b813101cb4beee8baf4421e227ac3733ded89d68a1c63eb612fb0f769f73439. 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/PTOV10900161.
Portugal - Variações - Guitarra Portuguesa
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xca097cd1ed9e8050c2633238ff629f81dd1c1ed7c94de0f3708728734e166bcc. Chain 2 (Bitcoin): anchored in block 957122 (2026-07-08T03:39:04Z), 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/DEU241124497.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb9ff7e8b59040716c455d7a48edb62cccbbc3fef1dd179968aac471f137061b9. 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/DEU241124500.
Memórias da Guitarra Portuguesa e a Guitarra do Século XVII
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1161bf94e78b746b1a604efca2cd9b83f9a96c267c19be63e873f242a9269246. 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/PT9BY0300010.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb5daa4b116ae0f39230c3cdbf930206e5086fb78d0640b29a0382b48a2aaab20. Chain 2 (Bitcoin): anchored in block 960258 (2026-07-30T12:45:34Z), 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/PT9BY0300008.
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 0x1c872c54e6917c909cdbdd0ea90a9858b8bb6e2848a96fd268a9d56b6042e0fa. Chain 2 (Bitcoin): anchored in block 960241 (2026-07-30T09:58:01Z), 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/PT9BY0300009.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f6b4432b3e55301e4ca77b58db1a44ab446c4af7268bb51802419b6a66cb7e6. Chain 2 (Bitcoin): anchored in block 960489 (2026-08-01T00:40:43Z), 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/PT9BY0300012.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa17fccd9303d9f6b0912239ebba441fe46edfc9d75eb7d4e80d41821e41af608. Chain 2 (Bitcoin): anchored in block 960309 (2026-07-30T20:35:49Z), 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/PT9BY0300014.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c1c0a37a85f43ade464488f0c88cdc416243f5bcace84524b2eab0d8e9042bf. Chain 2 (Bitcoin): anchored in block 960360 (2026-07-31T06:42:11Z), 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/PT9BY0300016.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x15a71b08492e124eb5e7d07f71ed70b25f622561f17293b1fb46142dc4acfed4. 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/PT9BY0300019.