Back catalog
Previously released recordings or compositions, typically more than three years old, that continue to generate royalties. Back catalogs are highly valued assets in publishing and often command premium acquisition multiples due to their proven, predictable revenue streams.
Articles about Back catalog

Copyright Chain of Title in Music: How to Establish and Verify Ownership
Proving who actually owns a song or master is rarely straightforward; missing split sheets, conflicting society entries, and legacy transfers create real operational risk. This guide lays out a step-by-step approach to build and verify a reliable copyright chain of title for both compositions and sound recordings, listing the exact documents, registry checks, APIs, and red flags you should use.

DistroKid Metadata Requirements: Preparing Your Catalog for Accurate Rights and Payments
Getting metadata right separates paid royalties from errors and lost revenue. This guide lays out DistroKid metadata requirements and the exact fields, identifiers, and formatting that determine how recordings and works are matched and paid across stores, PROs, SoundExchange, and The MLC .