String Quartet No. 20 in D Major, K. 499 "Hoffmeister": I. Allegretto

Recording identifiers

ISRC

USB8U1800655

CopyrightID (CopyrightChains transaction hash)

0xd1b23e406f0618863196b7a4fadf0329bd238d9d6d2d8407344d1ee329fb4e4f

Copyright registration time

2026-07-07T20:04:07+00:00

OpenTimestamps proof evidence

Bitcoin-attested timestamp

2026-07-08T03:39:04Z

Bitcoin block

957122

Canonical record hash

sha256:25081e7ff9c48ef8c536e0bfda50c935e0b6c95ab4c7bfd3c27cbfdf650fb89f

• Verify the CopyrightID on CopyrightChains
• Verify the Bitcoin block independently
• Read the machine-verifiable OTS result

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.