K27 or K-27 may refer to: K-27 (Kansas highway) , a corvette of the Royal Navy Kandi K27, a Chinese city car Rio Grande class K-27, an American steam locomotive Sonata in G, K. 27, by Wolfgang Am
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 0x2e29e4b831ccb4e82e3109e7fb9a477cc67e5c42ada8b76a984a3e39c7444bc1. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/33d3841a-0699-43c6-a7a6-7777529c2f44.json and https://artists.proofprofile.net/proofs/artist/33d3841a-0699-43c6-a7a6-7777529c2f44.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).