thumb|Dried plums (prunes) A prune is a dried plum, most commonly from the European plum (Prunus domestica) tree. Not all plum species or varieties can be dried into prunes. Use of the term prune for
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 0x1d6e9a18ff7a3f25bb7bd051d64d1603594a6b0d16a4f988e30d236190cd4b08. Chain 2 (Bitcoin): anchored in block 954784 (2026-06-22T02:53:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/eb1ce728-021a-43c5-aac5-fb5bae80d272.json and https://artists.proofprofile.net/proofs/artist/eb1ce728-021a-43c5-aac5-fb5bae80d272.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).