Delta commonly refers to: Delta (letter) (Δ or δ), the fourth letter of the Greek alphabet D (NATO phonetic alphabet: "Delta"), the fourth letter in the Latin alphabet River delta, at a river mout
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 0x12b58421398c11cd7dbdb2142fbafc3dc5ff3c76e5fbf8e27a96e103269bc731. Chain 2 (Bitcoin): anchored in block 954043 (2026-06-17T04:15:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3fa18ab2-11d4-41f3-98b6-19e33a943408.json and https://artists.proofprofile.net/proofs/artist/3fa18ab2-11d4-41f3-98b6-19e33a943408.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).