Lenny Popkin (born May 30, 1941) is a saxophonist whose style is most closely associated with the school of Lennie Tristano, with whom he studied and performed in the 1960s. He is married to Tristano'
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 0x3ff59b0562c7ea5f8bde3aa41d0f9d50df43a9b00c9dcc18d2e4cc2a7af10d4d. Chain 2 (Bitcoin): anchored in block 953803 (2026-06-15T15:41:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/e8b468a5-f1f2-458f-b6f7-0c07e9b86e6b.json and https://artists.proofprofile.net/proofs/artist/e8b468a5-f1f2-458f-b6f7-0c07e9b86e6b.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).