Mattr Corp., formerly known as Shawcor Ltd., is a Canadian materials technology company, based in Toronto, Ontario, and listed on the Toronto Stock Exchange. It specializes in providing services to th
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 0x04129072741865091f55ac378e4466961470f5cb089ffe006596825403bf4dff. Chain 2 (Bitcoin): anchored in block 954647 (2026-06-21T04:36:58Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d728b09a-9089-493b-9f67-c367fbf728f2.json and https://artists.proofprofile.net/proofs/artist/d728b09a-9089-493b-9f67-c367fbf728f2.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 0x13a995c1c79fa87fd7d2349c6e375afff8016b2026756ddff90a8aeb4d9c9169. Chain 2 (Bitcoin): anchored in block 958428 (2026-07-17T15:15:14Z), 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/QZTB32473003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x12c72074ccf1e75875f016ce64430427ab018104aa4284cf9d28aa98e997f49d. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/QZTAT2551393.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9b59b5995a368f865e5bddd3bb96f58538dcb96326c2208e010ddd08d54527a8. Chain 2 (Bitcoin): anchored in block 958432 (2026-07-17T15:43:17Z), 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/QZWFT2510438.