Marga Anna Johanna Höffgen (26 April 1921 – 7 July 1995) was a German contralto, known for singing oratorios, especially the Passions by Johann Sebastian Bach, and operatic parts such as Erda in Wagne
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 0xadfab236ff77028cc94d051e2ac63d4a75508981d8c2dd11ff0df03ac39e0221. Chain 2 (Bitcoin): anchored in block 953626 (2026-06-14T11:41:45Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/227381b1-403c-4956-a4ff-41915c9d5945.json and https://artists.proofprofile.net/proofs/artist/227381b1-403c-4956-a4ff-41915c9d5945.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Wagner: Siegfried, WWV 86c (Recorded 1960) [Live]