Passer is a genus of sparrows, also known as the true sparrows. The genus contains 28 species and includes the house sparrow and the Eurasian tree sparrow - two of the most common birds in the world.
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 0x39128c2867af96a7822cbfd755099e9330323f496f75e218d5858dce2704f583. 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/f24485c9-8134-4a2f-8ae3-6c2c49b0d310.json and https://artists.proofprofile.net/proofs/artist/f24485c9-8134-4a2f-8ae3-6c2c49b0d310.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).