"Black Hole Sun" is a song by American rock band Soundgarden. Written by frontman Chris Cornell, the song was released in May 1994 by A&M Records as the third single from the band's fourth studio albu
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 0xc543c6f0dbc522247ea043ce3ff5e8333f45b2619aa75a901145b117e16dc6dc. Chain 2 (Bitcoin): anchored in block 953778 (2026-06-15T11:57:35Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/c4547ea6-6528-4aa0-b471-bd96289f6645.json and https://artists.proofprofile.net/proofs/artist/c4547ea6-6528-4aa0-b471-bd96289f6645.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 0x4f3b16ce2a8c32a8f0f2a4e50c2e8937c177ecb09efd49e6f06ae1b1380d755a. 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/GBQRF1101689.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9426546b1022f6a11194986011162a3f799a63c2c950ea5ab3772bcd1b91ec12. Chain 2 (Bitcoin): anchored in block 958708 (2026-07-19T09:08:25Z), 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/GBQRF1206151.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x02e7ee1b63a40c0f3483e524acb92d790c415ccd8ed8ad28908a58b4d597d94e. Chain 2 (Bitcoin): anchored in block 958774 (2026-07-19T22:39:56Z), 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/GBQRF1214393.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x59ccfe0bccf664cc0d6ef1a2c5e6b1569e2fd32361c7b0b1d32c3ce5dab7a087. 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/GBQRF1204993.