昨日への手紙

Recording by Off Course.

Recording identifiers

ISRC
JPTO08300270
CopyrightID (CopyrightChains transaction hash)
0x9ddb5aeb2e9715cb3cc06a8a14315e94af4e71ccd22518a7cd3b519603c5c43d
Copyright registration time
2026-06-11T20:53:26+00:00

OpenTimestamps proof evidence

Bitcoin-attested timestamp
2026-06-13T15:41:10Z
Bitcoin block
953528
Canonical record hash
sha256:58c70be863c30ddb15c4545268a685c7b6ef0558bebfaf9ecfd29495b206bf6e

What this proof establishes

This recording belongs to ProofProfile's historical evidence base derived from the pre-2022 AcousticBrainz and MusicBrainz corpus. ISRC is the stable recording-level bridge from that source corpus to the authoritative cc-db-prod track record.

CopyrightChains and Bitcoin OpenTimestamps make the exact committed record independently verifiable today. The cryptographic proof does not by itself establish authorship or ownership of the underlying recording.

Read the complete pre-generative-AI provenance and verification method.