Jonathan Greenstein (born November 1, 1967) is an antique Judaica authentication expert. He is the owner, chief expert, and president of J. Greenstein & Company, an auction house in the United States
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 0x5c00ffb374ffdc5bdb60d4eedd79006824768e963294bd6dea3d4bdc9c2ec252. 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/8dc40a0d-eac0-4804-9f23-43330944491e.json and https://artists.proofprofile.net/proofs/artist/8dc40a0d-eac0-4804-9f23-43330944491e.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Vol. 1 (feat. Gilad Hekselman, Victor Gould, or Bareket & Mark Whitfield Jr)
Yuval's Cubism (feat. Gilad Hekselman, Victor Gould, or Bareket & Mark Whitfield Jr)
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp 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 0xd41a8146c30bccd4397d75fe5bfe77fcc085f7523fcd7f4a90cf43396f4ea418. Chain 2 (Bitcoin): anchored in block 958774 (2026-07-19T20:03:27Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USAAY1600004.
Grey Skies from the Atl (To a Broken Israeli Heart)