Extant is the opposite of the word extinct. It may refer to: Neontology, the study of extant taxa Extant hereditary titles Extant literature, surviving literature, such as Beowulf, the oldest extan
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 0xc948f489a305558b2510e6be442ff3e94dee925c1bcab737e21b15b9c6c9bb78. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b2f5bdf3-432b-427d-a7a2-e2b38b2dcbbb.json and https://artists.proofprofile.net/proofs/artist/b2f5bdf3-432b-427d-a7a2-e2b38b2dcbbb.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).