thumb|Gruppo Sportivo, 1978 Gruppo Sportivo are a Dutch pop band from The Hague, formed in 1976, who enjoyed a measure of international success in the late 1970s and 1980s. They had hit songs with "He
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 0x2390b291f60871e78a2927cccc2e5fb15c7d8563f7b910a9dad8fcc83db5d927. 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/a7d7f031-ddcb-46b7-980f-751a64ced147.json and https://artists.proofprofile.net/proofs/artist/a7d7f031-ddcb-46b7-980f-751a64ced147.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 0xafb27090027229138ed6110c87d823ef4e07044d4ed69d488203ff42532386bc. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200500 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9ff83a8b86ff23ec1fd6a5732b6c67f9dc31f76d97b01bed80f2b791f9eec81b. Chain 2 (Bitcoin): anchored in block 958541 (2026-07-18T11:37:54Z), 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/NLA200200493 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa84acc032fc2a86785a83480a887e09cd228f6b479ff4268ccf73a5d67a20094. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200489 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc02501736e424e748689728a909a786c6ce9b7f5b4d16eb4565e80e0332bfd91. Chain 2 (Bitcoin): anchored in block 958286 (2026-07-16T12:43:37Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200492 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x74c0879ea9b3d6787e3680be8d7f77b6d26f44a012e583e1e036b4e7d7b817bf. Chain 2 (Bitcoin): anchored in block 958216 (2026-07-16T00:00:34Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200495 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x92bf571a9d7f43a457d78cdbf5a532db223979193e9b4944c51b0d7f3a25b640. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL2094000049 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd978bcbe4cc9de694437c3b48e1825c3d66093ba003170ebf239b0d041ffc31f. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NL2094000050 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c4625a1f1c47d857cdbe6a0164796032ecc5a5694083c72753e40873d29bf6d. Chain 2 (Bitcoin): anchored in block 958631 (2026-07-19T00:50:09Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200483 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xca1471d6e77b75f28a4bb2545b5928eeb6f74e50ef6560cb33543c28055801d0. Chain 2 (Bitcoin): anchored in block 958622 (2026-07-18T22:58:55Z), 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/NL2094000052 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc44736a51466fb2adcc66a1f5d10db935f5bf361f06d31485f2a69a38aa4bdab. Chain 2 (Bitcoin): anchored in block 957882 (2026-07-13T16:48:10Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200498 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x32102fb048a0c3d97ae3a75f0624929d2f89a5578831b157b84b5c1d76f5a39c. Chain 2 (Bitcoin): anchored in block 958878 (2026-07-20T12:32:15Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200485 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x811f68eb3e1430e39556e2f1aface46cd244a4d1a94ba9c465277e929b0bc03e. Chain 2 (Bitcoin): anchored in block 958650 (2026-07-19T03:36:41Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200497 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7532ca319b6a170e24d64a94e1327576adf6827ed1cc435f71f07e3952be9ee6. Chain 2 (Bitcoin): anchored in block 958422 (2026-07-17T13:35:31Z), 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/NLA200200491 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbca6738801e12b64ca91c4e55039c0308c3a3820bb425c079c549398d1db0461. Chain 2 (Bitcoin): anchored in block 958558 (2026-07-18T13:44:16Z), 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/NLA200200486 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2f3b6d6f7d7d97602d16b7ea6c539c98eb136e7a17bb20c07027bee6d7fd64e7. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200496 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa323ecedc572a0337b6805313be198c1298c59c419d456924a43f1da8b7a5607. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200488 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe37c13685b44419c5cd74e76c9b835e9bb0aee4c990584ba43ea49d0b2d7cab9. Chain 2 (Bitcoin): anchored in block 959065 (2026-07-21T22:00:50Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLA200200490 — a six-check JSON result.
I Don't Think So / Click Here (2021 Remaster)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe37c13685b44419c5cd74e76c9b835e9bb0aee4c990584ba43ea49d0b2d7cab9. Chain 2 (Bitcoin): anchored in block 958517 (2026-07-18T07:54:29Z), 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/NLA200200490 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e29114890f62a9653701635162a2436b1760b8cce7802e458db48e79d67524b. Chain 2 (Bitcoin): anchored in block 958965 (2026-07-21T04:29:05Z), 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/TCAHM2344194 — a six-check JSON result.
Rare Tracks (For Collectors Only) [Remastered 2024]
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x30a6f0dc3279ad73e59534ee4e555bc4bdec1637ae039ff5b28862a77b57a7ff. Chain 2 (Bitcoin): anchored in block 958834 (2026-07-20T05:55:47Z), 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/NLH3R2400001 — a six-check JSON result.
Out There in the Jungle (Again) [Single Edit]
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x800ec21eaf953fa60c9bc3d320fe19b2c6ff05ee450255b2f9eadcba71dd2b79. Chain 2 (Bitcoin): anchored in block 958455 (2026-07-17T21:28:36Z), 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/NLH3R2400004 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x01b0e8e21acc535f717f039c4f6d7fdf6e8195071052d8968365442a8d3b3654. Chain 2 (Bitcoin): anchored in block 956745 (2026-07-05T05:33:35Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLH3R2400005 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf5e92cb9398fbfc86277c2e0a442eb2714ef4289f594ca0bb1b5200e19e03a70. 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLH3R2500002 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf5e92cb9398fbfc86277c2e0a442eb2714ef4289f594ca0bb1b5200e19e03a70. Chain 2 (Bitcoin): anchored in block 957782 (2026-07-13T00:52:48Z), 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/NLH3R2500002 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x800ec21eaf953fa60c9bc3d320fe19b2c6ff05ee450255b2f9eadcba71dd2b79. Chain 2 (Bitcoin): anchored in block 958185 (2026-07-15T18:19:04Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLH3R2400004 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x01b0e8e21acc535f717f039c4f6d7fdf6e8195071052d8968365442a8d3b3654. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLH3R2400005 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa9964086148caf357faace3a9bb2b9186e6abb0af1bb91c9fd38318d690a78ca. Chain 2 (Bitcoin): anchored in block 958180 (2026-07-15T17:59:52Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLH3R2500004 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc86884c716bf51cd4d5d2618f12b7c2c2d7746ef20eaceba30653ce13d0185f5. Chain 2 (Bitcoin): anchored in block 957774 (2026-07-12T23:51:20Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLH3R2500005 — a six-check JSON result.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6ab8d3a18d52951f2ddcec60d9e579ca805ba97a05567d8829d1b8df09c07b7e. Chain 2 (Bitcoin): anchored in block 958286 (2026-07-16T12:43:37Z), 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 at https://artists.proofprofile.net/api/v1/bot/ots/verify/track/NLH3R2400003 — a six-check JSON result.