Chor Leoni is a low voice choir based in Vancouver, British Columbia, Canada. The group was founded as Chor Leoni Men's Choir in 1992 by Order of Canada recipient Diane Loomer, C.M. (1940 - 2012), and
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 0x78fa5f5a4d07e82672d97bd6f0f8ba813dc33e9ce24087b1cf19efe815fc309c. Chain 2 (Bitcoin): anchored in block 953997 (2026-06-16T20:07:57Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/2635a433-1d19-4c84-896f-fba7b94fbc1c.json and https://artists.proofprofile.net/proofs/artist/2635a433-1d19-4c84-896f-fba7b94fbc1c.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 0x2abd32fb943e090f8c1c6ce9654463a39f3f2d3dd2f17d5494beb094935121e3. Chain 2 (Bitcoin): anchored in block 958749 (2026-07-19T15:48:23Z), 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/CA5S21800005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x889ab8fb29c88ac48d98d3f5387fad645bbf8d6a0015d4965c18d931a3e0198c. Chain 2 (Bitcoin): anchored in block 960497 (2026-08-01T02:22:04Z), 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/CBB472200018.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7b6e1a787ac8973612590780fa1652cb9b5c9bdc430f098f2365869e497c3317. Chain 2 (Bitcoin): anchored in block 960463 (2026-07-31T20:42:35Z), 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/CBB472200019.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9b476cf0e6b030a5c349fadfa0c0a0f08d7ee629773de777036cb3098514ff13. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/CBB472200021.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x471ef39f3ea24ecdd71e64bb2e78b2e8627cbe534287878c2de455bd250a0864. Chain 2 (Bitcoin): anchored in block 960403 (2026-07-31T13:04:34Z), 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/CBB472200024.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x21a7683bc80a2b86e9e8a79e6f9123897d38d9d77a569d61e289bede6ade6da2. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/CBB472200030.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xba63cc5cd4250301360932e4b80ae8c2e30ba1430ecf129b9855d9a87dcd8d6b. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/USAKS1400042.