Guro Kleven Hagen (born 11 May 1994) is a Norwegian violinist raised in Fagernes. She is the first concertmaster at the Norwegian National Opera and Ballet orchestra as of January 2018. Biography I
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 0xac83fe23c4768faac682529c4ea552e964c1b23e4d85c23e8e14b9be43b7877a. Chain 2 (Bitcoin): anchored in block 954588 (2026-06-20T19:15:05Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/bc29d36c-c9ff-47d1-9a5b-46364609aa46.json and https://artists.proofprofile.net/proofs/artist/bc29d36c-c9ff-47d1-9a5b-46364609aa46.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Guro Kleven Hagen – Bruch 1st and Prokofiev 2nd Violin Concertos
Fait Pleurer Les Songes – Ravel · Poulenc · Prokofiev Violin Sonatas