Tjeerd-Pieter David Oosterhuis (; born 25 December 1971), also known as TJ Oosterhuis, is a Dutch musician, songwriter and producer mostly known for his work with Kinderen voor Kinderen. He worked wit
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 0xb80fd5746493233e40a418d19ac5cfb04516845f46696760a80d460c570ab70f. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/997ac091-d521-43c8-8fb9-f77a73145b56.json and https://artists.proofprofile.net/proofs/artist/997ac091-d521-43c8-8fb9-f77a73145b56.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x64158c67c043b8bb2af355bb8a90ad2af93a743a518d0bbf1c8094028f5e4881. Chain 2 (Bitcoin): anchored in block 958520 (2026-07-18T08:19:09Z), 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/NL4WT2200089.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xba9ce35e2a6ebbc77bb11e033cdc244c92386ad7cfc27e27f088d98c86892669. Chain 2 (Bitcoin): anchored in block 958601 (2026-07-18T19:27:02Z), 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/NL4WT2200106.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfea84a05e1be622405dda1503cdd4ebba0f498afca289358f9e156393b9f4f91. Chain 2 (Bitcoin): anchored in block 958489 (2026-07-18T04:13:26Z), 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/NL4WT2200123.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9e405962a4895882aea029ae2cc1ff796b1f274a19bdaa93f89df7f5b7a3017a. Chain 2 (Bitcoin): anchored in block 958468 (2026-07-18T00:27:51Z), 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/NL4WT2200136.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd7c9f9114d90815442cc46c3fab9c7992fe49f0b99a1c9ca2479201e590bf0a4. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/NL4WT2200122.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xae454abe6c694434c296935354564026188e6732fad3f92087a2af08c4089e8e. Chain 2 (Bitcoin): anchored in block 958276 (2026-07-16T10:20:17Z), 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/NL4WT2200161.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb628a739a1adaca976946401ba35c47af9050a0b1ed9f44125ec882e220322fe. Chain 2 (Bitcoin): anchored in block 956738 (2026-07-05T04:47:21Z), 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/NL4WT2200173.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x945bc2f1da973abf55557e93e90defc33d0dc4816d3d4145417fd2366b888f0e. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/NL4WT2200180.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdca60f3de1f815634c527deff59b1d3d2b722ceef8077dba61ef33ddce52411c. Chain 2 (Bitcoin): anchored in block 958846 (2026-07-20T10:46:43Z), 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/NL4WT2200199.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf84134c542f3b7e643bb0428b24e3e1d8fdb721f50689cae0f92c14b5b37be94. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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/NL4WT2200211.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe4831c24604ed0477f6b38e4849780f11298f5baa74b7048ee5b0738a88ca65a. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/NL4WT2200216.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x622954c68f0bfc4546e18f70fd46b1c0525635a63e3564ee5e25b73d977b5def. 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/NL4WT2200218.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9e405962a4895882aea029ae2cc1ff796b1f274a19bdaa93f89df7f5b7a3017a. Chain 2 (Bitcoin): anchored in block 958617 (2026-07-18T22:07:13Z), 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/NL4WT2200136.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6540b5f18db9cc68100246f0f52b28517feee064a389fde665b6dc685e2f5c2a. Chain 2 (Bitcoin): anchored in block 958700 (2026-07-19T08:09:50Z), 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/NL4WT2200217.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf84134c542f3b7e643bb0428b24e3e1d8fdb721f50689cae0f92c14b5b37be94. Chain 2 (Bitcoin): anchored in block 956728 (2026-07-05T01:43:49Z), 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/NL4WT2200211.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdca60f3de1f815634c527deff59b1d3d2b722ceef8077dba61ef33ddce52411c. Chain 2 (Bitcoin): anchored in block 958377 (2026-07-17T06:48:00Z), 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/NL4WT2200199.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d852166c062b188193f1569c3b33c0e3c463b048586a305724f560baaed8eff. Chain 2 (Bitcoin): anchored in block 957801 (2026-07-13T04:17:08Z), 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/NL4WT2300017.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8d181b7ea2c40c8159f90e7d5c9534906e2324d31dacabbdb15e975b56570e41. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/NL4WT2300029.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xac4ed86573614a1151a2e4d460d7d31d6e64bc83eb408129dcaeb08a13084721. Chain 2 (Bitcoin): anchored in block 956711 (2026-07-04T22:48:52Z), 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/NL4WT2300080.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x06fcf09f467836455358a42dac72c93d5402e084492462f2bba5cc8bb4651d94. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/NL4WT2300088.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x88be859f3b5fd06c4a02decea7c33726915348a99629b4aa262a9fb8bc4a4e0b. Chain 2 (Bitcoin): anchored in block 958401 (2026-07-17T11:10:25Z), 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/NL4WT2300118.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf67c3166bdaf8e4fc214152734b4b891d0362878784e8387da2ea15dcfeebd3b. Chain 2 (Bitcoin): anchored in block 956728 (2026-07-05T01:43:49Z), 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/NL4WT2300151.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6db5fee92607811529b4a7e2f83d45e1c6a23a221b99c240fdad652fda76bdda. Chain 2 (Bitcoin): anchored in block 958493 (2026-07-18T04:34:53Z), 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/NL4WT2300171.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe90e303e1d1d4f5d0025778d210023d32da0b35e1812020b8f2d6faeee3c14e7. Chain 2 (Bitcoin): anchored in block 956776 (2026-07-05T10:59:37Z), 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/NL4WT2300188.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xddb268e522cbad2c950e9c06ee51a7c6610e7910483f065c07e7ad1decd397ec. Chain 2 (Bitcoin): anchored in block 956637 (2026-07-04T10:56:23Z), 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/NL4WT2300208.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3395928ce1c589a80e1635f24e0bb2ba40a461e16e3f2cc7044800afaea71e24. Chain 2 (Bitcoin): anchored in block 958397 (2026-07-17T10:29:45Z), 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/NL4WT2300286.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x719ce5ec55c187456d6ac7de523162077ef9ff3819dc8198943846977522c308. Chain 2 (Bitcoin): anchored in block 958480 (2026-07-18T02:58:58Z), 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/NL4WT2300323.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x30f2a76271064458bd52e313372a101b976482150451ecab48f1e107dfeb849f. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/NL4WT2300355.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7473cb113fe8d18b1523ef1917a27b49d3f5bc2e9f5f08bd7518887666750da4. Chain 2 (Bitcoin): anchored in block 957866 (2026-07-13T14:54:25Z), 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/NL4WT2400053.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc97868c910c3c3b586de2d09063df9fee7f6873a6ab6f33cc452ca8ab3737af7. Chain 2 (Bitcoin): anchored in block 956420 (2026-07-03T00:42:11Z), 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/NL4WT2400082.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9926c72ebfd5e5d64748b88a0ca5083476f282c168ceab3242f4f1e62506afaf. Chain 2 (Bitcoin): anchored in block 958401 (2026-07-17T11:10:25Z), 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/NL4WT2400115.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed6980907526ec10cec3c23490024dd01b07525fdf37cff5e31083ccb484a434. 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/NL4WT2400103.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x98dd362be586f7f8d261927cc86f61ee19b809c487e72ad1be042d0367ddbb9b. Chain 2 (Bitcoin): anchored in block 957867 (2026-07-13T14:55:20Z), 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/NL4WT2400172.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1c6412b8148af4de5ca854da2649ae93870fa6ac4d5a9531ad4140cc38e8e44b. 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/NL4WT2400313.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa4ccb9ad6074324dd034be8993e3aef9afaba065b1bac9513a73605c73325532. Chain 2 (Bitcoin): anchored in block 956476 (2026-07-03T09:04:44Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL4WT2500138.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8f17910ef9ea593506cc2e4c07437ee841dce09485e3b8a7dc01e5c493ab491e. Chain 2 (Bitcoin): anchored in block 956891 (2026-07-06T07:16:32Z), 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/NL4WT2300327.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x56c5763b530d6aef733c681f64895075836c2d4f36ff7803303e2d14991ea2f1. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/NLXV42300004.