thumb|300px|Josephine Lang Josephine Caroline Lang (14 March 1815 – 2 December 1880) was a German composer. Josephine Lang was the daughter of Theobald Lang, a violinist, and , opera singer. Her mothe
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 0x2771fecc9a4af88c707a7ca48dffd3fc40d3e94264d9ecf297179fff1884a11f. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cbf02256-ff61-4c36-8ab0-30d4deb56bde.json and https://artists.proofprofile.net/proofs/artist/cbf02256-ff61-4c36-8ab0-30d4deb56bde.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.
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 0x77b6436ee9a04b5de882199c41b19255dd05dd59b8b08a85f7470c8fd262fe5f. Chain 2 (Bitcoin): anchored in block 960348 (2026-07-31T05:17:02Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEE210047201 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x742c49b6ffbaf047e8462b7a8201ba9e28b16917f28ae27e728443cf321cb226. Chain 2 (Bitcoin): anchored in block 960473 (2026-07-31T22:27:44Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DEE210047214 — a six-check JSON result.
Lang: Liederbuch, Vol. 2: No. 16, Herbst-gefühl (Arr. for Double Bass and Piano by Lorraine Campet)
Liederbuch, Vol. 2 (Arr. for Double Bass and Piano by Lorraine Campet): No. 16, Herbst-gefühl
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x232050e999ba86e647aca40b5d63cc7dc0e712314b1e3aa9a78d10d11b1c16b1. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FROV62338719 — a six-check JSON result.
Lang: Deutsche Lieder, Op. 14: No. 1, O sehntest Du Dich so nach mir (Arr. for Double Bass and Piano by Lorraine Campet)
Sechs Deutsche Lieder, Op. 27: No. 6, Ja, zu Tod möchte ich mich lieben (Arr. für Gesang, Hackbrett, Akkordeon, Kontrabass und Klarinette von Patrick G. Braun)