Osvaldo Costa de Lacerda (March 23, 1927 – July 18, 2011) was a Brazilian composer and professor of music. Lacerda is known for a Brazilian nationalist musical style that combines elements of Brazilia
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 0x9af91023c26368d5e2969ef36ef419f1151b0e96fbbc686c69154778eb4d1fe8. Chain 2 (Bitcoin): anchored in block 954533 (2026-06-20T08:57:02Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/a72d8a2c-bf60-49d0-8a4d-89afd01568ef.json and https://artists.proofprofile.net/proofs/artist/a72d8a2c-bf60-49d0-8a4d-89afd01568ef.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Choir of Gonville & Caius College, Cambridge
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 0x9e25d1d18959453c861429b242acf7360c884ced473fb6be12c28cc0e99e4e70. 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/GBEBL1514708.
Marcas d'Água: Música Brasileira para Clarineta e Piano
Sonata para Clarineta e Piano: III. Rondó Allegro Grazioso
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe801df69e418932f35b4ddc15aaa6bdfed9ec1fff6eb47156c970a4e3d3e5fb7. 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/BRPUI0500503.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed4e33e18d3379c5ebf0f6e93d7177a118330ee4d052fb16c725f516f9474390. Chain 2 (Bitcoin): anchored in block 960362 (2026-07-31T06:58:00Z), 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/QM4TW2097341.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4ce5ad475d92678b67b8ae3587f80acf42cb1ddda140ed72388cb4d2629b1f26. Chain 2 (Bitcoin): anchored in block 960459 (2026-07-31T20:22:46Z), 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/QM4TW2097344.
Obra Integral para Piano de Osvaldo Lacerda, Vol. 3
Obra Integral para Piano de Osvaldo Lacerda, Vol. 6
Obra Integral para Piano de Osvaldo Lacerda, Vol. 5
Obra Integral para Piano de Osvaldo Lacerda, Vol. 4
Obra Integral para Piano de Osvaldo Lacerda, Vol. 2
Obra Integral para Piano de Osvaldo Lacerda, Vol. 1
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc98f04fd67b7ecd1181735264001a8512a4b8d661110b54483afce75741ec8a9. 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/DEN421105001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xeee89e4340ed4ec0509fb81933da22603cec9f2744e31af0aea89f3c33ad0f0c. Chain 2 (Bitcoin): anchored in block 960368 (2026-07-31T08:26:41Z), 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/DEN421105002.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x111128176946280bcb4205cfe13007cae01a8cdde635b504603de564754021fa. Chain 2 (Bitcoin): anchored in block 960291 (2026-07-30T18:23:33Z), 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/DEN421105003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x93cdba3b1e1ee7e4a41813131fc7fcd9c4a3e1eb374ef690799938476a64c1c5. Chain 2 (Bitcoin): anchored in block 960418 (2026-07-31T15:20:15Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEN421105011.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xce39bd793e8b79cc1d257f1d23609e35873875ba52492db9ddca083a3210895e. 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/BXSVC2300011.
Paisagem Brasileira - Flute and Piano Music from Brazil
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe7b5f71791960780734d2fac02f954c32c1dfd3e74d7d4561eb4b81af9129dd8. 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/GBABV0611137.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf6370beff4f77b6d91d6e75da8204a1f2ddcd36797a8fa0c0a8065b4d8231fb5. 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/GBABV0611145.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf623af9410c20f639b3a49589e25d73b1628f1b266f417b195f4a254d688eb7f. Chain 2 (Bitcoin): anchored in block 960368 (2026-07-31T08:26:41Z), 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/DENB21510516.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d855d8b8d76279fc771bdc241891e45a2797b597e8d079fec43a44be30a0d82. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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/GBSMU1978987.
Fronteras Latinas, Choros, Tangos y Valsas
Percussion Solos and Percussion in Chamber Music
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd30fe8be773e64c0d7bc00a43e13e413af292846be9aea60a5cb8a5995c8af5d. Chain 2 (Bitcoin): anchored in block 960468 (2026-07-31T21:25:57Z), 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/ITC471822392.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1967eef310fceb4df36dab5dd9909eb9a035f8e56df20d3fdd2ea5940e09b22b. 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/BR1HK2400010.