Karel Vlach (8 October 1911 in Prague – 26 February 1986 in Prague) was a Czech dance orchestra conductor and arranger. He founded his first orchestra in 1938. Many important composers, instrumental
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 0xbb2e2858573bdaa3a09f809de1891acbc10a9aabfbe59be0c53856069efb6e4e. Chain 2 (Bitcoin): anchored in block 953696 (2026-06-14T21:45:57Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/72f4a23f-00f6-439a-b72b-a8fc15cd52eb.json and https://artists.proofprofile.net/proofs/artist/72f4a23f-00f6-439a-b72b-a8fc15cd52eb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
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 0xe6d7949bdf96dc10536c53e286432489b16fc189a346972aa35d3c94ce3af186. 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/CZA166600175.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x656690f219f930adcf20d4e330f3cd97e98b32b6afdc2951413cbd566429fe64. Chain 2 (Bitcoin): anchored in block 960403 (2026-07-31T13:04:34Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/CZA161540509.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8b61753c6f0087bf7b461cf62077e62b96c2dc6af923ebfacec435104ecbb258. Chain 2 (Bitcoin): anchored in block 960222 (2026-07-30T07:48:45Z), 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/CZA167400112.