Sérgio Assad (born 26 December 1952) is a Brazilian guitarist, composer, and arranger who often performs with his brother, Odair, in the guitar duo Sérgio and Odair Assad, commonly referred to as the
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 0xef53c7d5c297c04dbbb5a0eee00511c00eb36bdf3032eb66e2f74cdfd19cbf29. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0f6a9c30-7c66-4f62-a688-6a1afe24fd84.json and https://artists.proofprofile.net/proofs/artist/0f6a9c30-7c66-4f62-a688-6a1afe24fd84.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 0x39d6fe17a9203e53d246bba17b4ebc1bf47e82526381ef6b469dc3f6c5197fe5. 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/USNO19950502.
Vardar's Boat - based on Macedonian traditional
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4a8a0aff2fe4997f0f2da0e45a8404a4d55b82f5923d2f1958cfaba8f62bd4f0. 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/USNO19950507.
Fantasy on Dark Eyes - based on Russian Traditional
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xceafd25eba76dedcc934fdfb3cbd2f8f30b01ca8c6d60fc1bcb97f287a5d34a7. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USNO19950503.
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 0x68fbe282bbf3d8df6a709b71717b42545a8bbb7bf0433d9f8b29109a8b659cd2. 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/USSM10313240.
“Mikis” Concerto Fantasia for Guitar & Strings
Heitor Villa-Lobos: Obra Completa para Violão Solo (Remasterizado | 2020)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfcdb225c2e7b5aa4dba0827eb12b919111a76fd423822df4b640ac78a8d62d5c. 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/BRKUA0113903.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd39619b84bef1725cc68f9801b226701296598936eb648d89ec08293ea57ca7c. 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/BRKUA0113905.
Suite Popular Brasileira: Mazurka-Choro - Remasterizado | 2020
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff4d863c2948dfa9a4584b7df24c82848587e00d21ebd851ded6fdd4541d37d0. 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/BRKUA0113906.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5ec60e4a83af55f1d7a6484adafaad653ef9bd0970b626f95e4ac92ea792fd2c. Chain 2 (Bitcoin): anchored in block 960160 (2026-07-29T22:48:59Z), 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/BRKUA0113901.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb36da0f485c8f93253ea0ba4e2ef4351dc606e2810ba7e7389b68803ad90571b. 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/BRKUA0113902.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2f8a514a3239552a1d332034762256647c679ade15fa90e94d461c4b70b5c9d3. Chain 2 (Bitcoin): anchored in block 960473 (2026-07-31T22:27:44Z), 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/BRKUA0113904.
Invitation - Summer Strings - The Old Man Di Sergio Assad (For Two Guitar)
The Italian Guitar Campus Series - Michele Reali
Assad: Colloquial Preludes: No. 3 in G Major
Sergio Assad: Naoussa Concerto & Concerto do Rio
Mozart in the Jungle, Season 3 (An Amazon Original Series Soundtrack)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x01fb59734ff29b1ca6c2424908bb7d9089ead4eb796a61e0ad6b83f79e68c6ae. 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/USSM10302462.
Pereira, Villa-Lobos, Reis & Others: Works for Guitar
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x795257001090630fe9277e22168d045af60a93c2d31c1df7656755625f2176e4. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/HKI191944314.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x69f2401e08c510f0f76fe1f46fd1c7a778bb6ea04f7a87c323c55dacb58d87d3. 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/CNUM71600027.
Guitar Exam Pieces from 2019, ABRSM Grade 8
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x40ffa950cd197ff0c1217ad1b8ef75dcfaf3d3b98c6427f3a78b74e686b97151. Chain 2 (Bitcoin): anchored in block 960209 (2026-07-30T05:15:54Z), 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/GBEYQ1866421.