The Da Capo Chamber Players are an American contemporary music "Pierrot ensemble," founded in 1970. Winners of the Naumburg Award in 1973, its founding members included composer/pianist Joan Tower, vi
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 0xc80a2ed3b7023721dc2a4d1289d3862eb38687c2a9b99ce0ca7d05912118bbd2. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/82f4d12e-2be7-4cbf-ab1a-a1240b893265.json and https://artists.proofprofile.net/proofs/artist/82f4d12e-2be7-4cbf-ab1a-a1240b893265.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Schoenberg: Pierrot Lunaire, Op. 21 & Herzgewächse, Op. 20
Pierrot Lunaire, Op. 21, Pt. 2: No. 8, Nacht
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 0xa17af7615f0ac8711fce0eb97538d73b5998964ab038b21e04f3e878a516917f. 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/USCRS0690328.
Pierrot Lunaire, Op. 21, Pt. 2: No. 13, Enthauptung
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x15075093c8c4d2262f41a9de40ecf7646cae08828b6defa1d2f3512d74fe6291. 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/USCRS0600323.
Pierrot Lunaire, Op. 21, Pt. 1: No. 1, Mondestrunken
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x847c325d4d2906d87220afacdf3d7d43365981e09949669eb9914cff5a86b222. 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/USCRS0690321.
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
Pierrot Lunaire, Op. 21, Pt. 3: No. 18, Der Mondfleck
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xad314633c88d79c34ceb0fa4a45aebc77ce8aa1475b10dd172f332b0f60eb0db. Chain 2 (Bitcoin): anchored in block 960317 (2026-07-30T21:35:24Z), 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/USCRS0600328.