Lutra is a genus of otters, one of seven in the subfamily Lutrinae. Taxonomy and evolution The genus includes these species: Extant species Extinct species Image Scientific name Common name D
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 0x174f22bbe34f72ab57e1d2c008720451579b6c0311dfd4e92f7a4616e4994ee6. Chain 2 (Bitcoin): anchored in block 953630 (2026-06-14T12:06:27Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/3025b383-5f84-4afe-83cb-44f5e4ec8767.json and https://artists.proofprofile.net/proofs/artist/3025b383-5f84-4afe-83cb-44f5e4ec8767.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 0xfda0de00fae9f07258d12642adfec6bafd497ba72bcf5bde613074b081db67a0. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/QM42K1827549.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x19a2c8f357c66520749883e76a5fa9cbdc2a099fc950ddcf88a37f77d4b063f0. Chain 2 (Bitcoin): anchored in block 959010 (2026-07-21T13:22:35Z), 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/QM42K1806262.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbd230c9b7896d42061778cbf051d817da66d2b3ca4200020a534cc590a24da75. Chain 2 (Bitcoin): anchored in block 957573 (2026-07-11T13:43:13Z), 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/QZKDK2092756.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x379efdd8278a08069ce5ba4ef489dc14028aa380dfd99df7fc49d095f0f85cd9. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/QZMHK2017315.