Sir Cameron Anthony Mackintosh (born 17 October 1946) is a British theatrical producer and theatre owner notable for his association with many commercially successful musicals. At the height of his su
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 0x31439a511bf8dce1de6a323f7f4d468a07c4d2c864eef653491a9c5e923ada3a. Chain 2 (Bitcoin): anchored in block 954062 (2026-06-17T07:39:10Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/46b53c60-ba4d-48eb-ba96-ce59d65e3f09.json and https://artists.proofprofile.net/proofs/artist/46b53c60-ba4d-48eb-ba96-ce59d65e3f09.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Stephen Sondheim's Old Friends: A Celebration (Live at the Sondheim Theatre)
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 0x10d701384d175d7d6cc671975f5113380faa1099912e28f9a6dbedb666968ff6. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/USRH12300374.
Stephen Sondheim’s Old Friends Original West End Concert Company
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc03da06a8603f753291eaad7afe71524de791b05d5ddaa4876ea4428a1cd2763. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/USRH12300398.