thumb|right|Björn Jensen at the Munich Filmfest 2010 Björn Jensen (born 12 January 1965 in Hameln, Germany) is a German filmmaker, consultant and producer. Career Jensen studied German and Medieval L
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 0xff09bb85d69dbb2a469bcf4538121a6639be8d2b3883c0475961fee783f2ad79. Chain 2 (Bitcoin): anchored in block 954002 (2026-06-16T20:47:12Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/329cc070-9535-4c13-a28f-051e3e5808e0.json and https://artists.proofprofile.net/proofs/artist/329cc070-9535-4c13-a28f-051e3e5808e0.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.