William R. Flagg (March 11, 1934November 19, 2024) was an American country and rockabilly singer, who was the first to use the term rockabilly. Life Childhood and youth thumb|Bill Flagg's record
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 0x04aa9b053fd3ebd3d5378cf94a6ed0a9ff6b4f7c7b3c4e850a4c65c2fa4dfcd3. 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/553f693b-ddbb-46b5-9480-33f5aa5564fb.json and https://artists.proofprofile.net/proofs/artist/553f693b-ddbb-46b5-9480-33f5aa5564fb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).