The pleurae (: pleura) are the two flattened pleural sacs filled with pleural fluid that surround each lung, and lines their surrounding tissues. They are formed of two opposing layers of serous membr
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 0x3a84869342f273a305ad41679c7892ed115146f860b0a9a08625f22af3f6a952. Chain 2 (Bitcoin): anchored in block 954603 (2026-06-20T21:47:54Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c27aec52-b1eb-4568-bbb6-5ead6eb4c57a.json and https://artists.proofprofile.net/proofs/artist/c27aec52-b1eb-4568-bbb6-5ead6eb4c57a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).