Marks may refer to: Business Mark's, a Canadian retail chain Marks & Spencer, a British retail chain Collective trade marks, trademarks owned by an organisation for the benefit of its members M
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 0xd80fe4c6fb253033d88841f0c877b57656b81dfacbcaee4e26aa828cc26b134e. Chain 2 (Bitcoin): anchored in block 953791 (2026-06-15T13:40:30Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/de276c39-15dd-47b3-a3d4-150d76abbb36.json and https://artists.proofprofile.net/proofs/artist/de276c39-15dd-47b3-a3d4-150d76abbb36.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 0x1d35a1c27cbfd28c7a7c01cfddbf9f1c350fbd66cd3c934a45be9229ae3291f1. Chain 2 (Bitcoin): anchored in block 958567 (2026-07-18T15:22:40Z), 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/TCAIN2475308.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x44ec3d4a98fe69bd8a243325125326436774edef8c0ab0efbf5fb00cd36f2c8f. Chain 2 (Bitcoin): anchored in block 957754 (2026-07-12T21:26:22Z), 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/TCAJC2475428.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc20665f707bc454d8aa88b389a2cad90901524b335acec638d7a5b3300c6a0ca. Chain 2 (Bitcoin): anchored in block 958170 (2026-07-15T16:21:50Z), 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/TCAJH2507263.