thumb|upright=1.2|A cup of espresso served in Ventimiglia, Italy thumb|An espresso being pulled from an E61-style espresso machine with a bottomless (naked) portafilter, 2014 Espresso (, ) is a concen
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 0x9f2377017c8a8022059c4e897028e55a4b0051c6f7c309b4ea20b251aa492800. Chain 2 (Bitcoin): anchored in block 953626 (2026-06-14T11:41:45Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/23ccc2a7-30a9-40d1-bc09-ad355b3eb44f.json and https://artists.proofprofile.net/proofs/artist/23ccc2a7-30a9-40d1-bc09-ad355b3eb44f.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaf80a2cba10cdbf31e76f38914e4482968ed2418e38d643abaaaee810a9d90f0. Chain 2 (Bitcoin): anchored in block 958388 (2026-07-17T09:14:21Z), 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/IT00D9931101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc5c8ed8b18099c963df2fec0e88b4073559b7d2e891c89e8a9c9b948e60973a9. Chain 2 (Bitcoin): anchored in block 958246 (2026-07-16T07:55:47Z), 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/IT00D9931108.