One of the earliest successful blogging tools was Movable Type. Like Blogger, Movable Type promised push-button publishing, but because it was software that you could download and run on your own server, it offered the potential for greater configuration, customization, and improvement than Blogger's service did.

Movable Type is written in Perl, a language that served both the developers and the user community in two significant ways:

• Perl is common and well supported on almost all Unix or Linux operating systems, allowing software written in Perl to run on a huge variety of systems with no additional effort from the developer.
• Perl applications are compiled at run time, requiring that they be distributed in source-code form, not as an opaque and inscrutable binary.

With the source code in hand, Movable Type users were able to extend the software to add features the developers hadn't imagined or couldn't afford to build. As the number of third-party enhancements grew, so did the community … until the developers released version 3 in 2004 and announced they were going to charge for the software that they had previously been giving away free. Author Mark Pilgrim explained it this way:

Movable Type has never been Free Software, as defined by the Free Software Foundation. It has never been open source software, as defined by the Open Source Initiative. Six Apart survived and thrived in the blogging community because Movable Type was “free enough.”¹

Adding insult to injury, the new version “required debugging” and “felt like a kludge.”² The community that had previously invested so much time in extending Movable Type realized that their efforts were wasted on a platform they could neither control nor trust. It wasn't the price, as Pilgrim noted, it was the uncertainty of what the developers might do or charge in the future.

For comparison, Pilgrim points to WordPress and b2. B2 was another early blogging tool, but by 2003, Michel Valdrighi, the original author, had abandoned the project.³ At that time a new group of developers adopted it and WordPress was born. Because Valdrighi had released his work under the GNU General Public License, the WordPress team could be confident that their work wouldn't be compromised if Valdrighi later decided to resume b2 development. Significantly, Valdrighi couldn't withdraw the b2 (or b2-derived) components from WordPress or demand payment from the WordPress developers for the use of b2 code.

In short, b2 and WordPress are what Movable Type is not: truly open source and free. That difference suddenly mattered to the Movable Type community in spring 2004, as they wondered what their future was and pondered blogger-programmer Matthew Thomas's warning: in the long run, “the usability of any non-Free software approaches zero.”⁴

In late 1996, UC Berkeley faced that risk with SWISH, indexing software used to make Web sites and other content searchable.⁵ Developer Kevin Hughes had begun the project in 1994 at Enterprise Integration Technologies, but as the company's interests moved on and changed hands, development slowed.⁶

Roy Tennant, then digital library project manager at Berkeley, had several projects that depended on SWISH, which was distributed in source-code form, but not covered by GPL at the time. “We were using it, and improving it, so I asked [Hughes] if we could continue developing it.”⁷ Hughes agreed, and in September 1997 announced that he'd been able to convince lawyers at Hewlett-Packard, which then owned the software as a result of a number of mergers, to release the code under the GPL:

Over the last four or so years I developed a variety of semi-free software at my old place of employment, EIT (Enterprise Integration Technologies). Although popular and used commercially in a few products, the software ended up being too much of a hassle for the company to support. I was effectively the contact person but never had the time to help integrate changes or even maintain a discussion list. To make matters worse, EIT was later purchased by VeriFone, which was later purchased by Hewlett-Packard, and the software became so meaningless to the company in the scheme of things that they were not able to figure out what to do with it for some time. In addition, EIT was dissolved a few months ago….

This week I officially received word from VeriFone/Hewlett-Packard's intellectual properties folks that [this software] is now covered under the GNU General Public License.⁸

Hughes later acknowledged the real importance of this decision when he explained that “copyright will still be held by VeriFone/Hewlett-Packard, but there are no longer any various potentially thorny legal issues that people wishing to make modifications or distribute in products need to worry about.”⁹

The same license that allowed continued SWISH development and helped WordPress to emerge from the abandoned b2 project assures that the contributions of everybody involved in a project are protected. The GPL allows for the sale of software, consulting, and support services, but it absolutely requires that the code be available to the community.

These protections, according to First Monday founder Rishab Aiyer Ghosh, encourage collaboration and innovation.¹⁰ And, according to MIT researcher Chris Hanson, they build community:

Why should others in the community trust you if you take their gifts and give nothing in return? People fear selfishness because it weakens community and trust.

[The GPL] protects the community against selfish behavior. Developers who use the GPL are saying, in the clearest possible way, that their motives are not selfish, that they can be trusted to participate in the community without holding something back for themselves.¹¹

And, as the SWISH and WordPress examples show, the GPL also protects communities against the waning interest of the original developer.