thumb|Jón Leifs (1934) Jón Leifs (; born Jón Þorleifsson; 1 May 1899 – 30 July 1968) was an Icelandic composer, pianist, and conductor. Life Jón Leifs was born Jón Þorleifsson, at the farm Sólheimar,
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 0x1b7707844f9165d569b389fc3b8e4048ed45eb0272473bc6c5fd1f4a1b159042. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/905f251f-8873-4407-9381-a5801d90727d.json and https://artists.proofprofile.net/proofs/artist/905f251f-8873-4407-9381-a5801d90727d.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Leifs: Edda, Pt. 2, Op. 42 "The Lives of the Gods"
Leifs: Lay of Helgi the Hunding-Slayer (The) / Groa's Spell / Landfall / Iceland Cantata