thumb|A PYREX 1-quart measuring cup manufactured after 1940, featuring graduations in United States customary units Pyrex (trademarked as PYREX and pyrex) is a type of borosilicate glass developed by
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 0xc5a279a8321db6dbea2794124ddc6b56430153d1b7f594ad363fcc40cfdcc494. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/53c29443-107b-4e8a-a0ff-ca7e1284ad86.json and https://artists.proofprofile.net/proofs/artist/53c29443-107b-4e8a-a0ff-ca7e1284ad86.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).