Checkpoint kinase 1, commonly referred to as Chk1, is a serine/threonine-specific protein kinase that, in humans, is encoded by the CHEK1 gene. Chk1 coordinates the DNA damage response (DDR) and cell
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 0x3da508082f1321e7976b00ca5b7d23ff023c23ce8bf9c02f6fff4a514eceb8af. Chain 2 (Bitcoin): anchored in block 953697 (2026-06-14T21:49:28Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/59113f57-8d24-4edf-86a5-11c04e92010f.json and https://artists.proofprofile.net/proofs/artist/59113f57-8d24-4edf-86a5-11c04e92010f.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 0x997582e6282a4b19e85bb72003a3f40afb636d83dd65669613d9fa770ec8417b. 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/ES71G2426797.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9d00832932385b6a98194b7ff99fa201825f472fbb24d7da716e0b314127ec86. Chain 2 (Bitcoin): anchored in block 956826 (2026-07-05T19:27:56Z), 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/ES71G2426796.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd10c4f8926def63340daf933b35997d8965b3ac661c4a75ffe80b19ef06d4acb. Chain 2 (Bitcoin): anchored in block 959034 (2026-07-21T16:34:25Z), 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/ES71G2426804.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x75b85166142c885f5b0ce6efc053419076d2ae234fdcbb9c252e6687d5b7b32f. 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/ES71G2426811.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x53736e75f5d284ea35a1c3ea7eb486ec848d23249b8d2d3df17d4d9b815ecac1. Chain 2 (Bitcoin): anchored in block 958331 (2026-07-16T21:55:37Z), 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/QM6N22573304.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x86a4af36658659d949a7b1dbef0fbdaa03b7bde8280d0bc4016c1e80b0f943e4. Chain 2 (Bitcoin): anchored in block 960500 (2026-08-01T03:13:03Z), 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/PTUM72100489.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5856870f51ec7321a11bc49705907c03da98e7bdb5a9f9e3038977d7d3f3ace7. 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/ES71G2101610.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa833dc8dcf3cf7ab5a63175b1159cd3473f34342c1305b5b3cda7d9d33a51cc5. 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/PT1HS2300125.