# Attribute with the local name “xmlns:dc” is not serializable as XML 1.0.

> Canonical HTML version: https://rocketvalidator.com/html-validation/attribute-with-the-local-name-xmlns-dc-is-not-serializable-as-xml-1-0
> Attribution: Rocket Validator (https://rocketvalidator.com)
> License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

Namespace declarations like `xmlns:dc` on an `<svg>` element are not serializable as XML 1.0 when used in an HTML5 document.

In HTML5 (the `text/html` serialization), namespace declarations using the `xmlns:` prefix syntax are not valid attributes. The HTML parser does not treat these as actual XML namespace declarations — it sees them as regular attributes with a colon in the name, which cannot be serialized back to well-formed XML 1.0. This commonly happens when SVG code is exported from graphic editors like Inkscape or Adobe Illustrator, which include Dublin Core (`dc`), RDF, and other XML namespace declarations that are unnecessary for rendering.

The SVG will render perfectly fine in browsers without these namespace prefixes. If the `<svg>` element doesn't actually use any elements or attributes from those namespaces (like `<dc:title>`), you can safely remove them. If it does contain such elements, those elements are also typically unused by browsers and can be removed as well.

## Invalid Example

```html
<svg xmlns:dc="http://purl.org/dc/elements/1.1/"
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
  viewBox="0 0 100 100">
  <metadata>
    <rdf:RDF>
      <rdf:Description rdf:about="">
        <dc:title>My Icon</dc:title>
      </rdf:Description>
    </rdf:RDF>
  </metadata>
  <circle cx="50" cy="50" r="40" fill="blue" />
</svg>
```

## Valid Example

Remove the namespace declarations and any associated metadata elements:

```html
<svg viewBox="0 0 100 100">
  <circle cx="50" cy="50" r="40" fill="blue" />
</svg>
```

If you still want to provide a title for accessibility, use the standard SVG `<title>` element instead:

```html
<svg viewBox="0 0 100 100" role="img">
  <title>My Icon</title>
  <circle cx="50" cy="50" r="40" fill="blue" />
</svg>
```