The GFDL was released in draft form for feedback in September 1999. After revisions, version 1.1 was issued in March 2000, version 1.2 in November 2002, and version 1.3 in November 2008. The current state of the license is

Material licensed under the current version of the license can be used for any purpose, as long as the use meets certain conditions.
• All previous authors of the work must be attributed.
• All changes to the work must be logged.

Some critics consider the GFDL a non-free license. Some reasons for this are that the GFDL allows "invariant" text which cannot be modified or removed,

• Most projects of the Wikimedia Foundation, including Wikipedia (excluding Wikivoyage and Wikinews) - On June 15, 2009, the Section 11

There have currently been no cases involving the GFDL in a court of law, although its sister license for software, the GNU General Public License, has been successfully enforced in such a setting. Although the content of Wikipedia has been plagiarized and used in

Some of these were developed independently of the GNU FDL, while others were developed in response to perceived flaws in the GNU FDL.
• GNU Simpler Free Documentation License
• Creative Commons licenses

• BSD license
• Copyleft
• Copyright
• Free software license