upright=1.35|thumb|Pope Benedict V (May 22–June 23) Year 964 (CMLXIV) was a leap year starting on Friday of the Julian calendar. Events Byzantine Empire Arab–Byzantine War: Emperor Nikephoros II
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 0xdf8ab2930c07034aa25aa54dc2e54b45fe395e307b563f05a41b105a17c708e4. Chain 2 (Bitcoin): anchored in block 953768 (2026-06-15T09:30:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c36a7a13-2b9e-450d-ba04-f02ab0320850.json and https://artists.proofprofile.net/proofs/artist/c36a7a13-2b9e-450d-ba04-f02ab0320850.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 0x6262ce128376d92028178d7f0d934ac7d8796944352e209d16f74817e454c023. Chain 2 (Bitcoin): anchored in block 958455 (2026-07-17T21:28:36Z), 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/NL5MF2100544.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf42715e66cb29320ef3f6f6933ecbff6664847e8cdb7e6585a2c107f96d70049. Chain 2 (Bitcoin): anchored in block 958621 (2026-07-18T22:59:44Z), 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/NL5MF2103720.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc03351e5f68cbb615aa8385a4ecd0f517e7911a63f04f41e300876ab36285211. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/NL5MF2103910.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa294b0746a900f017758258569551ae1861ec26cd8ff8e3490b6bdb8381169fc. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/NL5MF2104265.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xae9b358b74e6fcfbf664cc2ccf833b56e55e006ec1336cb3258c6d2a1c8fa027. Chain 2 (Bitcoin): anchored in block 957785 (2026-07-13T01:55:31Z), 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/NL5MF2104460.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe79fd8b603083e5710dd803d51fe7043c1a3cbfb4d06803c8077509ed83951a9. Chain 2 (Bitcoin): anchored in block 958800 (2026-07-20T00:52:19Z), 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/NL5MF2104536.