AX4 or AX-4 may refer to: Aeolus AX4, compact crossover SUV Axiom Mission 4, a 2025 private space mission to the ISS with astronauts from the space agencies of India, Hungary, and Poland/ESA AX-4:
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 0x84c1aae4fa50f602b04f04cb3a55b994af1441bc440160449b91a96af7a8ec98. Chain 2 (Bitcoin): anchored in block 954784 (2026-06-22T02:53:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/eff69703-9b19-4820-8b4a-00d6778072bf.json and https://artists.proofprofile.net/proofs/artist/eff69703-9b19-4820-8b4a-00d6778072bf.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).