The Mozilla Foundation

What you can and cannot do with our software products and code – independent of our trademarks – is governed by the relevant software licenses. For example, most Firefox code is released under the Mozilla Public License version 2.0.

The Mozilla Public License does not contain grant permission to use Mozilla trademarks, as is set out in its section 2.1. "Grants":

"Each Contributor hereby grants You a world-wide, royalty-free, non-exclusive license: (a) under intellectual property rights (other than patent or trademark)…"

In the following, the term “Mozilla software” refers to software developed and/or distributed by Mozilla or by one of its affiliates. If you wish to distribute Firefox and other Mozilla software branded with our trademarks, you must comply with the relevant software licenses, the Mozilla Trademark Guidelines and either the Unaltered Software Distribution Policy or the terms of a written distribution agreement with Mozilla.

Unaltered Software Distribution Policy

You may distribute unaltered copies of Mozilla Firefox and other Mozilla software from Mozilla.org without express permission from Mozilla as long as you comply with the following rules:

• You may not charge for the software. That means:
  • Distribution may not be subject to any fee.
  • Distribution may not be tied to purchasing a product or service.
• You may not collect personal information in the context of your distribution of the software.
• You may not add to, remove, or change any part of the software, including the Mozilla trademarks themselves. For example, you may not add any extensions to Firefox, change default settings, or alter search codes.
• You may not modify the installation process of the software or use it to install any other themes, plugins, extensions, or software.
• We suggest that if you want to distribute Mozilla software, you do so by linking to official downloads at Mozilla.org to help ensure safe, reliable downloads. For example, if you wish to directly distribute copies of Firefox yourself, you must distribute the latest stable version available at Mozilla.org.
• When distributing you must distribute the most recent version of Firefox and other Mozilla software.
• For Android versions of Firefox that you are distributing on a device: (1) the device must have at least 512MB of RAM; and (2) if the device does not have Google Play installed, you must have a means for providing the user with Firefox updates as they are released by Mozilla (see the release calendar).

Mozilla reserves the right to change this Unaltered Software Distribution Policy by posting changes on this webpage.

Modified Versions Require Prior Written Permission

The open source nature of Firefox and other Mozilla software allows you to freely download and modify the source code. However, if you make any changes to Firefox or other Mozilla software, you may not redistribute that product using any Mozilla trademark without Mozilla’s prior written consent and, typically, a distribution agreement with Mozilla. For example, you may not distribute a modified form of Firefox and continue to call it Firefox.

• Changes requiring Mozilla’s prior written permission include (but are not limited to):
  • Changing the default home page or adding bookmarks,
  • Adding, modifying, or deleting source files,
  • Adding, modifying, or deleting content from installer files,
  • File location changes,
  • Adding extensions, add-ons or plugins, or
  • Installing themes other than those available in the most recent stable version of Firefox available at Mozilla.org.

If you wish to distribute a modified version of Firefox or other Mozilla software with Mozilla trademarks please contact us with your request at trademark-permissions@mozilla.com.

Mozilla General Trademark Guidelines

Mozilla’s general trademark guidelines include more information about permitted uses of our trademarks.