"Sappy" is a song by the American rock band Nirvana, written by vocalist and guitarist, Kurt Cobain. It was first released as a hidden track on the AIDS-benefit compilation album, No Alternative, in O
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 0x8dea3944cf2f87f1e1622451d1a00306d2bfe6c8290b745ce405a7865093343b. Chain 2 (Bitcoin): anchored in block 953770 (2026-06-15T09:50:11Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b4744af8-55b1-412b-869f-86d2c2af7579.json and https://artists.proofprofile.net/proofs/artist/b4744af8-55b1-412b-869f-86d2c2af7579.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 0x3fbde9a38e35cea54e48f3a76c2991787deb4cf9bd439542a5fe35a91f0dc484. Chain 2 (Bitcoin): anchored in block 958106 (2026-07-15T05:35:13Z), 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/QZTAX2246139.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbaea5700a0e8367f7670deba9b82f80e6cc73be5ff79207fbc9d3522957e5140. Chain 2 (Bitcoin): anchored in block 958368 (2026-07-17T05:03:25Z), 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/QZTAX2247962.