John Barton Featherstone (May 7, 1949 – March 20, 2021) was an American junior college football coach. He was the head football coach for El Camino College from 1985 to 2015. With the Warriors, he hel
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 0x6ce7a27e998810889fb3cff769cf4e594a94bb9452d7b367942da9a8e2df6ad7. Chain 2 (Bitcoin): anchored in block 954587 (2026-06-20T19:10:41Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/baf95279-4154-46f6-87c3-6ec8aba6b5fe.json and https://artists.proofprofile.net/proofs/artist/baf95279-4154-46f6-87c3-6ec8aba6b5fe.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).