Katrine Madsen (born 7 March 1972 in Aarhus, Denmark) is a Danish jazz singer. Biography Madsen studied at the Royal Danish Academy of Music and has worked in Copenhagen on albums with transplanted
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1783c3a3cbacbf96385edb349e98db40f94a81ec56968b7858c342cecf75ae37. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/5cdd8d69-8132-46c9-9432-f1da62fd66fa.json and https://artists.proofprofile.net/proofs/artist/5cdd8d69-8132-46c9-9432-f1da62fd66fa.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Gershwin & More (feat. Jan Lundgren & Jacob Fischer)
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3a7f51773b4da97c0e0066f1fcf6625d3a7c39d29170e35424e4238a8f9b3e28. Chain 2 (Bitcoin): anchored in block 958134 (2026-07-15T11:31:02Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/DKEBA9908805.
Let There Be Love (feat. Svante Thuresson)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xaddd57b6802bbe28dff1da28816434e30a15eb02d09aa3ba066d5b7b2f6d6a31. Chain 2 (Bitcoin): anchored in block 958690 (2026-07-19T07:14:39Z), 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/DKEBA9908807.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x606cb883132736f77ee2b5ee8fd0f69c6f58030a815c543dd850b0bd85e21a01. 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/DK2A42100101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc633c1937a8d89e1854b477abb83a10cdf01833d1d4eb7610b49bf59245121b5. 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/DK2A42100102.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb115e48b9575345fa87c3b80605f25b636ffcef308c27bab298b22e60592b3bd. 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/DK9G52100203.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb58aabac67c8b5fd9140d53028649ea87ae6d26ca9594ca954652c1e862be33e. 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/DK9G52100204.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb294f58caa5b1e1fd82171a74837ac3462f793c90f7ab8e812d0f006c656fece. Chain 2 (Bitcoin): anchored in block 960354 (2026-07-31T05:48:18Z), 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/DK9G52100201.
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