The license under which the WordPress software and accompanying bbPress plugin is released is GNU GPLv2 (or later) from the Free Software Foundation. The full license is included with every copy of WordPress & bbPress, and you can also read the original license.
How it applies
Part of this license outlines requirements for derivative works, such as WordPress plugins or themes. Derivatives of WordPress code inherit the GPL license. Drupal, which has the same GPL license as WordPress, has an excellent page on licensing as it applies to themes and modules (their word for plugins).
We feel strongly that WordPress plugins and themes are derivative, and thus inherit the GPL license.
Is GPL a no-go for you?
If you disagree with some part of the GPL, consider using non-GPL forum platform such as:
- Simple Machines Forum (BSD license)
- Phorum (Phorum license – “BSD-like”)
- MyBB (LGPL)
The forum solutions listed above do not come with CMS functionality of their own, and will rely on their own add-ons or require custom work to function like WordPress.
A note on domains
- Do not use “bbPress” in your domain name, like: “bbpress-things.com”.
(Try using “bbp” or another variation instead)
- “bbPress” in a subdomain is fine, like: “bbpress.example.com”.
(We are only concerned about top-level domains)
- For more information read WordPress.org – Domains.