Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1993 used to present documents, including text formatting and images, in a manner independent of appli
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 0x7a1108c007a88feaab983e6bf170022a54759b7c1d9204478380e2599239b573. Chain 2 (Bitcoin): anchored in block 953877 (2026-06-16T02:39:16Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/021ff678-810f-4c58-a8f0-3fa4f7690041.json and https://artists.proofprofile.net/proofs/artist/021ff678-810f-4c58-a8f0-3fa4f7690041.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).