Wikipedia and the GFDL

A freely licensed adventure 2015-12-22

Wikipedia, since its very inception, has used the GNU Free Documentation License (GFDL, covered in an earlier post) to license its articles and many of its images. Compared to other, more traditional websites that offer their content under a less free, less open license, this is a big step — and it’s not an overstatement to say that Wikipedia exemplifies, if not leads, the whole gamut of user-contributed websites today. What does the GFDL mean for Wikipedia?

First, how exactly is Wikipedia content licensed? Here is the official license text from the Copyrights page:

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts.

As you can see, Wikipedia does not use the controversial Invariant Sections clause that the GFDL permits — that means there are no pages on Wikipedia detailing its philosophy that must be kept in derivatives (such as other websites that reuse Wikipedia content).

What does Wikipedia’s license mean for the average contributor? When you goto a Wikipedia page, hit “Edit this page”, make your changes, then finally hit “Save page”, you are licensing your contributions under the GFDL. This is because the edit page, similar in spirit to “clickwrap” licenses found on the Internet and in software, contains the text, “You agree to license your contributions under the GFDL” along with a footer with the text quoted above.

Now I expect that the average visitor to Wikipedia who makes a quick contribution (such as a spelling fix or changes some figures here or there) does not realize this fact. This might be a little problematic for Wikipedia, as there is no “I agree” button, or any other user interface element (such as a checkbox) that forces the user to agree to this license. In the past, the courts have found this to be a problem — in Specht v. Netscape Communications Corp. (2001), the court ruled that the Netscape license was not enforceable as there was no explicit “I agree” button for the user to click before downloading the software. The changes needed to ensure Wikipedia’s safety might be minimal — simply by preceding the text with ‘By clicking “save page” below, you…,’ for example. It would be interesting to see whether this is actually a problem legally.

What, then, does the GFDL mean for the established Wikipedian? Firstly, it means that there’s a slight learning curve — getting accustomed to the GFDL and the various restrictions and freedoms it poses is something that can only be learned through reading through the rather thorough documentation on Wikipedia itself. Second, it means that a lot of care must be taken to preserve edit histories.

Edit histories are the information you get when you click on the “History” tab of an article on Wikipedia; basic information about each revision to an article, such as the user name (or IP address, in case of anonymous contributors) and date and time of each revision, are presented. This list is necessary for copyright purposes; because Wikipedia articles are not copyrighted by the Wikimedia Foundation, or any other single entity, but by its contributors (due to standard Berne Convention rules), the list of contributors must be preserved throughout revisions in case somebody wishes to relicense an article (although this is unheard of as of yet) or more frequently, an article needs to be cited.

The preservation of edit histories is usually carried out automatically by the MediaWiki software; however, when merging two pages into one, for example, the origins of each portion of text must be noted on the attached discussion page of the resulting article.

Of course, this preservation of edit histories is not a burden associated exclusively with the GFDL; any Creative Commons license requiring attribution would also have the same burdens.

It turns out that the real restrictions of the GFDL (as used by Wikipedia, without the invariant sections clause) are only in the redistribution stage, the requirement to include the full text of the GNU Free Documentation License along with redistributed copies being the main one. Even if this is the only problem, it is a good enough reason to switch Wikipedia’s license — switching to a Creative Commons license will greatly increase the utility of Wikipedia content.