The Letter
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duration: PT2M28S
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explicit: false
by artist: Bobby Darin
in album: Darin 1936-1973 (Expanded Edition)
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  date published: 2017-03-24
genre: adult-standards
genre: easy-listening
genre: lounge
genre: vocal-jazz
genre: rock-and-roll
genre: rockabilly
isrc code: USUM71600943
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additional property: OTSVerifyInstructions
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  value: 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
subject of: OpenTimestamps Proof of Existence
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  description: Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfc378f8a3de3fee7f27cfb4dc82528e42aeb9979645b3622a33ef980f4577cb9. 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/USUM71600943.
  date published: 2026-07-08T03:20:19Z
audio: The Letter
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