Wilhelmus Jacobus Duyn (31 March 1937 – 4 December 2004) was a Dutch singer, actor, entertainer and voice over artist. Under the stage name Big Mouth he was co-vocalist of the Dutch pop music duos Mou
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 0x078fe7e02cdce871282205f17807c6bf518116a1ba81368c46dde727483f94aa. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/07981f49-4c8e-4fb0-b644-506cadf2a1a7.json and https://artists.proofprofile.net/proofs/artist/07981f49-4c8e-4fb0-b644-506cadf2a1a7.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Willem Duyn (Remastered 2023 / Expanded Edition)
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 0x52fa56d661a9cc1d5599d44aef9eb971c08d5c5d7b91b11e002c398d1c61edef. Chain 2 (Bitcoin): anchored in block 956738 (2026-07-05T04:47:21Z), 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/NLUM72300255.
Zal Ik Een Krekel Wezen - Remastered 2023
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0788f02424efeec68df84c89c99f14e4c268c7b49c4a06991fbd71c811bb1b3c. Chain 2 (Bitcoin): anchored in block 956560 (2026-07-03T23:28:02Z), 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/NLUM72300257.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5cc4c469228d1736d8fbd8939def934926ce0348e525a549981d5bd8cbdfaa1a. Chain 2 (Bitcoin): anchored in block 956551 (2026-07-03T21:18:05Z), 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/NLUM72300262.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62aa7221797350cddc4d651b4cbe2e433066bfc6a248dd865f35033d686d93ba. Chain 2 (Bitcoin): anchored in block 958060 (2026-07-14T20:39:42Z), 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/NLA241701299.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0be1dee9ce5c15b7a580a707dcc0fe6cf7d9955bf58f525b27a4547d2e25b0ac. Chain 2 (Bitcoin): anchored in block 958397 (2026-07-17T10:29:45Z), 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/NLA241701306.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4ffbc35b679f9452747c613b367eff34ee7e533c8018f81eb8214f7a8025d1b7. Chain 2 (Bitcoin): anchored in block 958447 (2026-07-17T19:47:19Z), 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/NLA241701308.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb7e2b46e17dc0a4ebdb1d4baa38bb6836fa23baaeb4b7d723250886d0b9542c9. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLK502300009.