Nevermind is the second studio album and major label debut by American rock band Nirvana, released on September 24, 1991, by DGC Records. It was Nirvana's first release to feature drummer Dave Grohl.
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 0x12da079b156e2e98cdba901f9092262db0751bf5da344096152fca53f0d7f8d1. 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/1769f811-4338-48b7-9268-c7b900d61f05.json and https://artists.proofprofile.net/proofs/artist/1769f811-4338-48b7-9268-c7b900d61f05.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Sonates en trio et a quatre parties pour violons, (ou) flutes traversieres, viole et basse continue, Op. 12, Concerto: I. Largo
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 0x8a46bd1f014e91954b5bfb6cf24d0bc5d6a9d9a2119e0562acb47a59180ba2d4. Chain 2 (Bitcoin): anchored in block 960236 (2026-07-30T09:37:10Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FR50X1523501.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x37c3f166f063900efdb812f3d4b85ad4896d98dd296028cb158b3303387ac83a. 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/FR50X1523502.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x962cd761eb110d3a50909604132e8734b3a32e33cbaa64619917b17216e2c4e9. 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/FR50X1523503.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xda8d6232971d0996d36061370f0e0117f0340b131165ffd9bffc38e32c755fe2. Chain 2 (Bitcoin): anchored in block 960294 (2026-07-30T18:46:00Z), 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/FR50X1523504.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x80dcd462761c050ce70c28ada1f87bb701c6c213491603f90a6545467af34c77. 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/FR50X1523505.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x65612da6837afb50384f698ea8e88fa1192bf058eb66a956efc14e90926b8a6b. 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/FR50X1523506.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3ce31983e5d6822ea4046efd38eb7db0dffe03d57654621be10da4e7e01d70f2. Chain 2 (Bitcoin): anchored in block 960441 (2026-07-31T17:29:52Z), 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/FR50X1523507.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa227119400a6c85cc79ff69d6792c6bc214e4b4b093bb05e57b1788471aea584. Chain 2 (Bitcoin): anchored in block 960223 (2026-07-30T07:51:46Z), 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/FR50X1523508.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f8d3afd45a8032103a0ad5a33ee0e407048706342be75525e5d36179a3014af. Chain 2 (Bitcoin): anchored in block 960376 (2026-07-31T09:09:19Z), 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/FR50X1523509.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x525a3c2f034cc2e52750e7025a027251bc68c7e7e6a3b29643cdd09dcbb4c1b8. 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/FR50X1523510.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xce62fd1300f9ae55e09dcb6048692c11f80eefef70ebbec5d8b06eeb2cef6b9c. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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/FR50X1523511.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1db7aa9a8259f0ce5c92725fdffc12d1822b7e77a7992cff8359dc4d073f2696. Chain 2 (Bitcoin): anchored in block 960340 (2026-07-31T03:15:04Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FR50X1523512.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e8cdd99dc8e76814278afe59f5287cb4177fe6d14ff5fbe6392ee2eda5cd854. 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/FR50X1523513.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0716cf27afb5c208fc54eec19ea95489b187607bec84ea259b74ecb1e19b9f1a. 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/FR50X1523514.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa06da01abbb40de7b1f3fd258570134336732523f3480222c2fd262f3be6d4bb. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/FR50X1523516.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x859a78fb668fad4fafdd72776bba68ac5c0773b4609f40e0df263aeb819530d9. 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/FR50X1523517.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa6a47267bcec9a8ea75a3853848186ef0ec3db48182b628226beb07c3c3b1ba0. Chain 2 (Bitcoin): anchored in block 960321 (2026-07-30T22:27:30Z), 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/FR50X1523518.