Sub-zero literally means "beneath zero". As such, it is usually used for negative numbers; the most common usage refers to negative temperature. Sub-zero can also refer to: Fictional characters S
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 0x26f31fc324377a023ac8f144c6609865ea46e7672520044f4c83ab2e1f371a15. Chain 2 (Bitcoin): anchored in block 953742 (2026-06-15T04:47:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8b6078bb-59c3-4d4c-bb28-7af83edfedc6.json and https://artists.proofprofile.net/proofs/artist/8b6078bb-59c3-4d4c-bb28-7af83edfedc6.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 0x21c19d7f811fe7614f216533f906b4598e41d2e227f5a76c19ee7d80f2059cf8. Chain 2 (Bitcoin): anchored in block 956728 (2026-07-05T01:43:49Z), 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/US4E40585701.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbb818fc4c50e559365d5d3ef39753c0919f2b0600460406b0e4fa359d7e19118. Chain 2 (Bitcoin): anchored in block 956422 (2026-07-03T01:01:38Z), 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/US4E40585702.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4bcaea4e63f12d0e10a0c6394062eb2dc578006a19e909d10463082019160c0e. Chain 2 (Bitcoin): anchored in block 958716 (2026-07-19T10:15:55Z), 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/US4E40585703.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x19150dbb691c300c18229d547e7ea843708be8e7c051e459a4540877bc0757bb. Chain 2 (Bitcoin): anchored in block 958711 (2026-07-19T09:26:32Z), 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/US4E40585704.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7fe6a9dd117a13100deff79aec119ac9320c0a56d4c07ec39d8a4bdc0c8d8ff9. Chain 2 (Bitcoin): anchored in block 956351 (2026-07-02T11:38:34Z), 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/USJ3V1038202.