OC Times is a barbershop quartet affiliated with the Barbershop Harmony Society. They earned second place silver medals at the International Barbershop Quartet Contest at Denver's Pepsi Center on July
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 0x2adf3c2be67b63297ea58a1d78d0c74221803af8c5cdc5a8c6f9b334fd35e36c. Chain 2 (Bitcoin): anchored in block 953768 (2026-06-15T09:30:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/bfd9fba8-54f8-4927-956f-27f802550967.json and https://artists.proofprofile.net/proofs/artist/bfd9fba8-54f8-4927-956f-27f802550967.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 0x4a2a399fedfb737635ce513d0b2c2aaf1ebb0555d5f34f153bbb128bce8f3843. Chain 2 (Bitcoin): anchored in block 958742 (2026-07-19T16:39:21Z), 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/USTC30706208.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x81b2dc073f50294d05a357811c0ff7b87fbd710ff39108c7813a6dd4cd94a505. Chain 2 (Bitcoin): anchored in block 958793 (2026-07-19T22:59:45Z), 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/USTC30706210.
Sold (The Grundy County Auction Incident)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc33f3a3bb459eab23281c745ad11a077236f3036df3765445907c2f9693ec199. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USTC30706211.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x85e5855c8d4e56f5a732b071d221e3862c01a321ea76921015dcc31c4a545b54. Chain 2 (Bitcoin): anchored in block 958340 (2026-07-17T02:40:15Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USTC30706215.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62522f4f86a041b7944bbdf4091f5c02c9a05a1ae062b1c8415ec852b0a86217. Chain 2 (Bitcoin): anchored in block 956790 (2026-07-05T12:31:54Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USTC30706217.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb2fdcd5603c957a4471f33052e310b8335e0ac7a615a9b5edd9e51e069c851b0. Chain 2 (Bitcoin): anchored in block 958157 (2026-07-15T13:14:32Z), 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/USTC30706225.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4424cf50e2ac8a57da1e6311d67b45a921e77b5826035527507a756e6a446ca5. 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/USR2X1000018.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9994776d1112151e016f48e6ce1cef46068cee863d74817ef12e88a5fd81bcfc. Chain 2 (Bitcoin): anchored in block 959047 (2026-07-21T21:34:15Z), 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 via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USR2X1000023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa274e123d8698ab0dba5abcd4010a4a4448903928a03503813d0aa7c42d1db28. Chain 2 (Bitcoin): anchored in block 958448 (2026-07-17T19:49:21Z), 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/USR2X1000026.