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# Previously released music, ISRCs and UPCs

An **ISRC** identifies a single recording, and a **UPC** identifies a release. You don't need either to release new music: we assign them for free when your release is approved. If a track is already out somewhere, mark it **Previously released** and enter its existing ISRC so its streams stay linked.

## What ISRCs and UPCs are

* **ISRC** (International Standard Recording Code): one per recording, for example `QT8JA2500001`. Stores use it to count streams and connect the same recording across releases. A recording keeps the same ISRC wherever it appears.
* **UPC** (Universal Product Code): one per release, a 12- or 13-digit barcode number. It identifies the single, EP or album as a product.

## New music

Leave each track set to **New recording**. When your release is approved, we assign an ISRC to every track that doesn't have one, and a UPC to the release. You'll see them on the release page afterwards.

An ISRC we assigned shows as locked in the builder: "Assigned by us and registered to this recording."

## Music that's already out

If a track was released before, with us or anywhere else, use its existing ISRC.

1. Open the track in the builder.
2. Under **Previously released**, choose **Previously released**.
3. Enter the ISRC in the **ISRC** field.

![The Previously released switch with the ISRC field and the option to reuse a recording](https://ammdistro.com/helpdesk/distro-builder-previously-released.webp =1200xauto)

If the recording is already on AMM Distro, click **Or reuse a recording already on the platform** instead. See **Single, EP or album?** for how this works.

A previously released track can't be approved without its ISRC.

### Where to find your ISRC

* Your old distributor's dashboard usually lists the ISRC for each track.
* In Spotify for Artists or Apple Music for Artists, look at the song's details.

### ISRC format

An ISRC is 12 characters: 2 letters for the country, 3 letters or numbers for the registrant, then 7 digits. You can type it with or without hyphens. If it doesn't fit this format, you'll see "Invalid ISRC format."

## Moving a whole release from another distributor

Use **Catalog Transfer**. It copies the ISRCs, the UPC and the original release date for you and marks the tracks as previously released. See **Move your catalog from another distributor**.

## When an ISRC is locked

If an ISRC has already been delivered to stores, the recording's details, credits and audio are locked: "This ISRC is already distributed. Recording metadata, credits, and masters are locked so every product stays identical." This keeps the same recording identical on every release it appears on.

## Common questions

### Can I use my own UPC?

The builder doesn't have a UPC field for new releases. If you're moving a release from another distributor, Catalog Transfer keeps its UPC.

### Does the ISRC change if I put a single on an album?

No. Reuse the recording on the album so it keeps the same ISRC and its streams stay together.

### Is a sped-up or remixed version the same ISRC?

No. A different version is a different recording, so it needs its own ISRC. Leave it as **New recording** and we'll assign one.

### I entered the wrong ISRC.

Fix it in the builder before you submit. If it's locked, send us a message from the chat on this page, or email team@ammdistro.com.

**Related:** [Move your catalog from another distributor](https://help.ammlabs.io/en/article/06-move-your-catalog-from-another-distributor-1q2aeyv/) · [Single, EP or album?](https://help.ammlabs.io/en/article/12-single-ep-or-album-19ktfpp/) · [Audio requirements](https://help.ammlabs.io/en/article/03-audio-requirements-m8wqre/) · [Check and submit your release](https://help.ammlabs.io/en/article/11-check-and-submit-your-release-1gcucgm/)