Robert John Lurtsema (November 14, 1931 – June 12, 2000) was a public radio broadcaster. Lurtsema hosted the classical music show Morning Pro Musica on radio station WGBH (FM) in Boston, Massachusett
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 0xab190209b6ebcc58744115bf6a343244be6b27846dadd5c7c744da887ca4f302. Chain 2 (Bitcoin): anchored in block 954784 (2026-06-22T02:53:59Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/ffc56f0c-b055-4450-b6cd-f0011fad9918.json and https://artists.proofprofile.net/proofs/artist/ffc56f0c-b055-4450-b6cd-f0011fad9918.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
The Christmas Revels: In Celebration of the Winter Solstice
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 0x8d36a27c34ede01175bd6a8d4f339761eae00d2e21aa773d8c4f20d4f1932718. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/US89R0512724.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd59d3a4aec9dd52bfdb07b8acb88c495b6c456cff6a9a6fe7f6dd7071bcf92dd. Chain 2 (Bitcoin): anchored in block 960368 (2026-07-31T08:26:41Z), 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/US89R0512732.
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0c4312b3996ffb5836c7abe597ccd4b1f457f84037501cfa91aab7d93b54f5b8. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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/US89R0512738.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0a9637bd85056fb2eeb2d32388affb0a0b992238b77eeb5b950bf6fa4be89666. Chain 2 (Bitcoin): anchored in block 960327 (2026-07-31T00:26:26Z), 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/US89R0512745.