Sedo (an acronym for Search Engine for Domain Offers and stylised sedo) is a domain name and website marketplace and domain parking provider based in Cambridge, Massachusetts and Cologne, Germany. The
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 0xdc2e9375ddd5989e004e23f10b773d73469d304c0be61660ba9521aed8f081f0. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/5d664b13-c56d-404d-a557-d09023606f2a.json and https://artists.proofprofile.net/proofs/artist/5d664b13-c56d-404d-a557-d09023606f2a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).