thumb|upright=1.25|right|Diagram showing the relationship between the zenith, the nadir, and different types of horizon The zenith (, ) is the imaginary point on the celestial sphere directly "above"
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 0x2cf4f848e8515e03eeace55c2d9432b77ee864f356ed3f5fb00c2deed96c7c97. Chain 2 (Bitcoin): anchored in block 953819 (2026-06-15T18:31:52Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/fb7d2d23-e92d-470c-9ffe-88a49c157222.json and https://artists.proofprofile.net/proofs/artist/fb7d2d23-e92d-470c-9ffe-88a49c157222.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 0xd0a7c9ac6a054be7b6a2fc451fdd47811a485cede2f5c2985f7f7f633db0d6e4. Chain 2 (Bitcoin): anchored in block 956484 (2026-07-03T10:47:44Z), 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/USANG2502249.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa52a88fb6031aa0a591ec417474495a79e7d775d62168feb2e7a5cf33d8d6892. Chain 2 (Bitcoin): anchored in block 958242 (2026-07-16T07:26:42Z), 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/USANG2502247.