4 Out of 5 Doctors was a Washington D.C.–based power pop band. They released an eponymous LP in 1980 produced by Alan Winstanley, and a second LP in 1982 ("Second Opinion", produced by Jeff Glixman,
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 0x9b6d1eb6e4d8a144ff1917be45257a3f436c1e15b708f31afbb0b21eb9544603. 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/4b74c99a-8f51-4cdb-add0-35021f26d241.json and https://artists.proofprofile.net/proofs/artist/4b74c99a-8f51-4cdb-add0-35021f26d241.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).