Stephan Henrik Barratt-Due Jr. (born 1 June 1956 in Oslo, Norway) is a Norwegian violinist, the son of violinist Stephan Henrik Barrat-Due (1919–1985) and Else Barratt-Due (b. Holst, June 1925). Bio
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 0x5920225d77f4731c748cbb5bd5504484024ac3f25fb5fcf98ab82ab4a1a2409a. Chain 2 (Bitcoin): anchored in block 953889 (2026-06-16T04:57:45Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/0dd01f3d-ef82-4afc-9f4c-9a5aeb9d86bd.json and https://artists.proofprofile.net/proofs/artist/0dd01f3d-ef82-4afc-9f4c-9a5aeb9d86bd.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).