Kato or Katō may refer to: Places Kato, Guyana, a village in Guyana Katō, Hyōgo, a city in Hyōgo Prefecture, Japan Katō District, Hokkaido, a district located in Tokachi Subprefecture, Hokkaido, Japa
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 0xa5af09dc52e77ecd3eb298e360e3510e8ce84c231c78124bfbf0ea7335e52b06. Chain 2 (Bitcoin): anchored in block 953699 (2026-06-14T22:00:24Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/690b4f6c-4be6-4bae-a068-af8bf2559bb6.json and https://artists.proofprofile.net/proofs/artist/690b4f6c-4be6-4bae-a068-af8bf2559bb6.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp 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 0x2c2bcf6d8a937685781a247aab71c8346a5b45044ba925cc28962c043cfec695. Chain 2 (Bitcoin): anchored in block 958774 (2026-07-19T20:03:27Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZDA82440160.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x957fa777f861e7421b77bc2ac41c7f840872c396d8257dd383b067c9bb391ebc. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZK6K2461562.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xccd9a3c01566c60be34140a28f0fb4de59d2366f874822d71b4cb29bae25eb61. Chain 2 (Bitcoin): anchored in block 958573 (2026-07-18T15:49:54Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/QZNWU2421078.