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 0x860a59848a2036fa3c8534df82ed8afe3072578542e142b1214e235ed08cb96c. 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/d592621f-6893-492d-b5bc-750412f12e70.json and https://artists.proofprofile.net/proofs/artist/d592621f-6893-492d-b5bc-750412f12e70.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
Juichen Voor De Sint (Nationale Sinterklaaslied 2021)
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 0x924e3b08ccf6210b3cb0489a30a84d8b66f8e115220e0cdfa89a89145e7f3a04. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/NL6HK2100004 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x052c38ba308572121de65f23640872474110d2722e5de186c625946e69316949. Chain 2 (Bitcoin): anchored in block 958749 (2026-07-19T15:48:23Z), 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/NL6HK2100008 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c20b8844e5b31ccdca32534b3cbea5a442e2185f9cf64597a2773a5f59280c9. Chain 2 (Bitcoin): anchored in block 958444 (2026-07-17T19:12:23Z), 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/NL6HK2100013 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfd533e486710ba6c7260acf657642314e2a6d9b915bd79d217abaf5b47a4afad. Chain 2 (Bitcoin): anchored in block 958650 (2026-07-19T03:36:41Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2200013 — a six-check JSON result.
Handjes In De Lucht (Nationale Sinterklaaslied 2023)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x63fa6e993225375937dd1b2c53d1610657c8e94a2185156677d1cf4fdba3f09a. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2300012 — a six-check JSON result.
Handjes In De Lucht - Nationale Sinterklaaslied 2023
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e13a67870bf75704b5dc74c7e748ce7ac6bddd9f603cb3571690ece382f1ad3. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2300010 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfa5b62f3caa03085d51c0024e46df3ee833e388b13a91723749067bc736a3f47. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2300014 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0632088acf8f950d26a3fefa9abaf72d2c08bde7d30f71a2be83b4747431ad77. Chain 2 (Bitcoin): anchored in block 960138 (2026-07-29T19:35:34Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2300015 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x50f21e90e3ba3770fd708859905d6f356ac3afcaddd88976332bd9e111834769. 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/NL6HK2300016 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3f4dae74bdf587c738d4c26d868caca2387c3a8a9d702bbcd665e8e4899e93a2. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2300017 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcd50f6be8fae1b1d1846cef054c8bfcd9e0069e9a5c1b532cdfd2cf5e13c1fd1. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2300018 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x384e4683c10f3bb2b00d0ec405388028754a572851ead71e4030baecbc930891. Chain 2 (Bitcoin): anchored in block 957061 (2026-07-07T16:07:00Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2300019 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3ccc6b5170714d8172d8e6d3be0e961a384285fc1919c7c797b4bdb3b2aa90dd. 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/NL6HK2300020 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd840277c74d594883e7c753997008d51a74cfdccd0a1820e1d7e7a207c68f8e3. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/NL6HK2300021 — a six-check JSON result.
Welkom Sint en Piet (alle bekende Sinterklaasliedjes)
Sint Alarm (Nationale Sinterklaaslied 2024)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe898252fe87cffbbc7ea189f7e94bf0e0b0e2328dab503f6c1a4eda2c9a13763. Chain 2 (Bitcoin): anchored in block 957770 (2026-07-12T23:17:00Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2400018 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x455492f91ade47bb7f149bb25c1192491fab1137c634ecc8d612396c20785561. Chain 2 (Bitcoin): anchored in block 959094 (2026-07-22T03:33:16Z), 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/NL6HK2400020 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0fd0cb413428e14cbb8b5496668a7c22aa4def34e0575571542b98661bcddbf7. Chain 2 (Bitcoin): anchored in block 959069 (2026-07-21T22:32:59Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL6HK2400017 — a six-check JSON result.
Total Loss (Nationale Sinterklaaslied 2025)