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 0x9cefe914c9775444d7cf9d0aaf58a147abc3c0f1ad9732a31cf3a4fb1c84c8cc. Chain 2 (Bitcoin): anchored in block 953742 (2026-06-15T04:47:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8a572274-f618-40d3-a1df-1dcc35c9c9c8.json and https://artists.proofprofile.net/proofs/artist/8a572274-f618-40d3-a1df-1dcc35c9c9c8.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Französisch für Anfänger A1_A2 (Audiokurs der französischen Sprache für Anfänger)
Chapter 01 - Französisch für Anfänger A1_A2
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 0xa0f4a052bb2e1e4f8358ff800404e6a570a2f2adcc9f6d6f67c4ec86e0c31b04. Chain 2 (Bitcoin): anchored in block 958552 (2026-07-18T13:15:29Z), 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/DE1JR2342337.
Chapter 02 - Französisch für Anfänger A1_A2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe9cdf52a6e70a7572c7abb04a74070fdd84fc7392b054a8e51c1a8649c2f63fa. 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/DE1JR2342338.
Chapter 05 - Französisch für Anfänger A1_A2
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x24250120035c2f1997227fcfc098ff0682976f550f3bfb35629e9f080e827c29. Chain 2 (Bitcoin): anchored in block 956857 (2026-07-06T01:26:17Z), 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/DE1JR2342341.
Französisch für den Urlaub A1_B1 (Audiokurs der französischen Sprache für Anfänger und leicht Fortgeschrittene)
Französisch für die Arbeit A1-B1 (Wirtschaftsfranzösisch Audiokurs)
Französisch für die Mittelstufe B1_Teil 02 (Audiokurs der französischen Sprache für leicht Fortgeschrittene)
Technisches Französisch A1-B1 (Audiokurs der französischen Sprache für Anfänger und leicht Fortgeschrittene)