ISWC: The Code of the Song, Not the Recording

When a song is recorded multiple times — a studio version, a live version, a cover — each recording gets its own ISRC. But the underlying composition, the melody and lyrics, has a single identifier: the ISWC.

The International Standard Musical Work Code (ISWC) identifies a musical work: the combination of melody and lyrics as created by the composer and lyricist. It does not identify a specific recording or a specific release.

A song covered by ten different artists has one ISWC and ten ISRCs (one per recording). A medley of three songs has three ISRCs for the source recordings and one ISWC for the medley as a new work, if it qualifies as one.

An ISWC looks like this: T-034.524.680-1. The T prefix indicates a musical work. The nine digits are the unique identifier. The final digit is a check digit.

ISWCs are assigned by collecting societies and publishers who are members of the ISWC International Agency, administered by CISAC (the International Confederation of Societies of Authors and Composers). In Hungary, the relevant society is Artisjus.

When you register a composition with your collecting society, they assign or retrieve the ISWC. The code is then used in royalty reporting to link performances and broadcasts to the correct rights holders.

If you write your own songs and register them with a collecting society, your compositions will receive ISWCs. These codes appear in the metadata that collecting societies exchange internationally, enabling royalty collection across borders.

This article is for information only.