# EPUBCheck RSC-015: SVG use without a fragment, how to fix it

Source: https://epubcc.com/epubcheck/rsc-015/ (updated 2026-11-04)

EPUBCheck RSC-015 is a usage message: “A fragment identifier is required for svg use tag references.” An SVG use element references a file without a fragment identifier; it must point to a specific element with #id. Without the fragment, the reading app does not know which shape to reuse.

- Official message (EPUBCheck 5.4.0): A fragment identifier is required for svg use tag references.
- Default severity: Usage

## Typical causes

- A use element written as <use href="icons.svg"/> instead of <use href="icons.svg#star"/>.
- Symbol sprites whose ids were removed when the SVG was optimised.

## How to fix it

1. Open the SVG file and find the id of the element to reuse.
2. Add that id at the end of the reference, after a #.
3. If the element has no id, give it one, then validate again.

## When it's not this

If the fragment is present but the id does not exist, the message is RSC-012.

## Sources

- EPUB 3.3, §6.2.2 SVG requirements: https://www.w3.org/TR/epub-33/#sec-svg-req (read 2026-11-04)

Message text and severity: EPUBCheck (W3C, BSD-3-Clause). Explanation: EpubCC.