Léo Ferré (; 24 August 1916 – 14 July 1993) was a Monégasque poet and composer, and a dynamic and controversial live performer. He released some forty albums over this period, composing the music 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 0xd2998d4eb6b81d9e3cf48bfffcea6b766fbf8ba7893035eca679adc0a68060df. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/de0b56bb-999b-4282-8250-25363cf383f3.json and https://artists.proofprofile.net/proofs/artist/de0b56bb-999b-4282-8250-25363cf383f3.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 0xa7a690c7409b35415f8dbe4ef0708b00cd285b5782f73b181b681e39062a1b79. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/FRDMD2200360.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3b657605d76f288d4395c3e00e7b297d3c6a911f501ce86511c916b92ed1babe. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/FRUM72302428.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x227ce430755ce5cfa96b57baa05e452ced7d5f63ecff0a6f4039ca31066e0179. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/FRZ016000150.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8e3acaa60e945c800f51f4739460bcf293ddd838b609e164f2cd5203139cfb9. 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/FRZ017100110.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xedcafab4252000848e94e2777eab131425e9618f61778ab0d358c79772ed7408. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/FRZ016900220.
Ferré / Transc Ducros: Colloque sentimental
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb5338c22778ce8f067fbe5710f3cafb5e9e2a964b7ff5fffc137e0045eec24d1. Chain 2 (Bitcoin): anchored in block 957046 (2026-07-07T14:04:01Z), 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/GBAYC1402760.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8e3acaa60e945c800f51f4739460bcf293ddd838b609e164f2cd5203139cfb9. Chain 2 (Bitcoin): anchored in block 960150 (2026-07-29T21:51:49Z), 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/FRZ017100110.
Ma France - Chansons Symphoniques (Live)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x95b7499d4c89f99bb889c426422f2f50868517e0464cb29e4cfa836631cb0ab9. 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/NLB151900684.
Muss es sein? Es muss sein! - Arr. for Cello, Strings and Percussions
Muss es sein? Es muss sein! (Arr. for Cello, Strings and Percussions)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xebd2d5f1dc09a9d1a61aa1609dc5552980b55dd4309577b112da18ff59c178ee. 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/FR50X2066001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd5745fcaf2b7720d6c8cfaa8b93a4368953d3ceab651787d9a30aa976ffb2c0e. Chain 2 (Bitcoin): anchored in block 960254 (2026-07-30T12:06:10Z), 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/FRZ131306200.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x03349da69c4652bfc3ffed937ca7892d118687d899c2e5c57790f83e5be45dbb. Chain 2 (Bitcoin): anchored in block 960223 (2026-07-30T07:51:46Z), 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/FRZ131306290.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6238e550cde92e1ed6f16a498b502fe3a464e0d52c7fcce19d3e559e7c1390aa. Chain 2 (Bitcoin): anchored in block 957041 (2026-07-07T13:25:45Z), 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/FRZ131007020.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc8b6f20132d0eaff75563f087fae0ce1b80c7653cc6ff33887fe6bd8897327c3. Chain 2 (Bitcoin): anchored in block 960334 (2026-07-31T02:19:15Z), 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/DEN961304450.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf41c298ad2eed7fe70e21bebdfcf32cdf23b3e99e61ad44d29153253f5183f5a. 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/DEN961304580.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8e3acaa60e945c800f51f4739460bcf293ddd838b609e164f2cd5203139cfb9. Chain 2 (Bitcoin): anchored in block 960117 (2026-07-29T14:28:24Z), 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/FRZ017100110.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8e3acaa60e945c800f51f4739460bcf293ddd838b609e164f2cd5203139cfb9. Chain 2 (Bitcoin): anchored in block 960344 (2026-07-31T04:14:58Z), 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/FRZ017100110.
Les grandes plumes de la chanson française
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xedcafab4252000848e94e2777eab131425e9618f61778ab0d358c79772ed7408. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/FRZ016900220.