Thomas Stewart Baker (born 20 January 1934) is an English actor and writer. He is best known for playing the fourth incarnation of the Doctor in the BBC science fiction series Doctor Who from 1974 to
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 0x5abd7e1acee12b698bc49f8906ed4b689dfbbb4d90fe2bd8ad6e652d4b1c493a. Chain 2 (Bitcoin): anchored in block 953741 (2026-06-15T04:44:49Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9ad636ae-8a9f-4a36-8d94-1aeb0442a357.json and https://artists.proofprofile.net/proofs/artist/9ad636ae-8a9f-4a36-8d94-1aeb0442a357.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).