Tante Leen (English: Auntie Leen, January 28, 1912 — August 5, 1992), real name Helena Kok-Polder, later Helena Jansen-Polder, was a Dutch folk singer from Amsterdam, Netherlands. Together with her fr
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 0xdef8910c90cbc90d0655f3d2e50982aea4f5e8af351e497092e8538d9fb3b252. 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/b9168f6d-679f-4beb-8b26-bc40bba87358.json and https://artists.proofprofile.net/proofs/artist/b9168f6d-679f-4beb-8b26-bc40bba87358.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
De Beste Stemmen Van De Jordaan (Mono Version)
Er Is Maar Eén Tante Leen (Remastered 2022)
Ik Gun Je Heus Je Borreltje Wel - Remastered 2022
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 0x34a5befbdbd370fbb2c64f3e445b28008b2b4c2b44109446bc5ecd7876508c9c. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), 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/NLUM72200641.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa19a5aa7dfb7e8badd311687ab9b463a7b28c96f61dc1bf71efaacb0a45ffc4c. Chain 2 (Bitcoin): anchored in block 958234 (2026-07-16T03:46:09Z), 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/NLA279503813.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb696609025df52709a5117ccd4dcbaf472f9d920a393dd80e0db6a0959abebfb. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/NLA275600051.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe5aa7014910826793b49d403aa54359f12bfcfeaf6fbfe1e858d5e245aa2c32c. Chain 2 (Bitcoin): anchored in block 958749 (2026-07-19T18:24:47Z), 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/NLA270600651.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x08143fdd7ec5aaf092c545217dc2d798c8466d20726494426cf13020d55c093a. Chain 2 (Bitcoin): anchored in block 958176 (2026-07-15T19:12:27Z), 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/NLUM71600792.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x04f54138e0f1109cff59b6a84f6889dd62082a88e24c90e6b9b2e7b3f82f0874. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/NLUM71801010.