upright=1.35|thumb|Saracen raiders sack Thessalonica (904) __NOTOC__ Year 904 (CMIV) was a leap year starting on Sunday of the Julian calendar. Events By place Byzantine Empire July 29 – Sac
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 0x07a7ff8b9b7f6f3217d55f4b6b5720a9914013ac329f2d2569b7a96ff7efd183. Chain 2 (Bitcoin): anchored in block 953713 (2026-06-15T00:33:41Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/85e882bf-4a7a-4b91-9359-8db542e293e1.json and https://artists.proofprofile.net/proofs/artist/85e882bf-4a7a-4b91-9359-8db542e293e1.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 0x97fb75fd6a93c16f480af63d267c209416aa4ad72af8a656947ba67a7dc8cabb. Chain 2 (Bitcoin): anchored in block 959043 (2026-07-21T18:40:26Z), 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/QZNWT2409268.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x794c8bf4931445574cccc0e453f8a5d89795f36730429c62e98b530620fd38cc. Chain 2 (Bitcoin): anchored in block 958761 (2026-07-19T17:49:48Z), 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/QZWFR2493707.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x132f81b8df6cecf96c3a8266bb6a3f8a57623d7a39b11a6a4cd587beebc6de1d. 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/QZK6L2501685.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5b81461850bc75532c1cde6df53ae59b32c5c8af6533f196d1fe1bf4b91aba3f. Chain 2 (Bitcoin): anchored in block 958779 (2026-07-19T21:08:39Z), 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/QZK6L2501688.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0ed541b7dfe2e6555860e1625d6bfdaf6b52c8b1c51bbedbe3ed871da0b19947. Chain 2 (Bitcoin): anchored in block 958985 (2026-07-21T08:39:15Z), 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/QZK6L2501689.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x731b3cc808327505d11ab86bdacc6054243517e6a34757634044e0233e451c9e. Chain 2 (Bitcoin): anchored in block 959128 (2026-07-22T12:33:25Z), 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/QZK6L2501690.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf3aa407ead009e48d0e06979f5e26d7c4094f5f4e378ef010a6821b96961d4ef. 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/QZK6L2501691.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x58b92de95740df3046be966aa10042ba379c8632bf244e8857c6ac57e7694158. Chain 2 (Bitcoin): anchored in block 958366 (2026-07-17T04:59:09Z), 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/QZK6L2501692.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3565c25c5bb93ce0f920b3767e85ad642967e272522b0c66b4381f16ef232279. 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/QZK6L2501694.