At the end of April, I wrote about the idea that usage of the GNU General Public License (GPL) is declining and concluded that although new, commercially initiated open source projects were indeed tending to adopt other licenses, the use of the GPL itself is still growing -- especially among projects in its core community of GNU platform development. This article explores why commercial projects pick particular open source licenses and what might happen in the future.

Dual licensing

First, a brief historical recap: During the "open source bubble" of the mid-2000s, driven to build Web-facing solutions on short timescales, many companies used a combination of Linux/Apache HTTPD/MySQL/Perl to prototype and iterate. They were able to do this because open source specifically grants the freedom to use those packages for any purpose -- to study them, modify them, and deploy them -- all without permission from any entity.

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The software that resulted worked really well, but when it came time to move to production, most companies asked for legal advice. As always happens when you ask your lawyer for business advice (instead of making business decisions and asking your lawyer to help you achieve them legally), they were told to play safe and buy a proprietary license to MySQL and Red Hat Enterprise Linux. Despite open source licenses offering everyone the freedom to use the software for any purpose, many companies were concerned that the GPL might force them to open up all their internal workings to the world.

A number of software entrepreneurs chose to base their business models on this fear. They selected the GPL for their software projects, not to promote some vision of digital liberty, but rather to exploit the fears of corporate legal advisers about the GPL. Called the dual-license model (referring to the software being available under both an open source license and a proprietary license), it depends on the software developer owning all the copyrights so that they can provide different license terms for paying and nonpaying users, and on the use of the most scary open source license possible in the eyes of inexperienced legal advisers. Today this means use of the AGPL, a variant of the GPL that is also triggered by Web deployment, unlike the GPL itself.

All the same, this approach is in decline. Corporate decision-makers have become more experienced, and their legal advisers have gained greater insight into the GPL. Purchasing decisions have come to revolve much more around the purchase of necessary services related to the software, and the GPL no longer shoos-in the business. Just selling services on open source software is not "sticky" and lacks lock-in -- the four software freedoms ensure that anyone can complete on service value.

Open core as a business model

As the scare value of the GPL declined, some business ventures switched to another approach. They tended to retain the GPL for the core project, hoping still to scare up a little revenue. However, more and more of them added proprietary layers on top, becoming little better than the proprietary vendors they claimed to replace. By making the features essential to enterprise deployment proprietary, they hoped to force adopters into their revenue funnel.

Moreover, since the proprietary software couldn't be used by the community, they faced no direct competition from community members offering better value points to their customers. The combination of enterprise compulsion and lock-in was very attractive, and many projects in the late years of the decade moved to this "open core" approach.

For the customer, the problem is that instead of delivering and cultivating software freedom, the open-core business model induces dependency on closed software and lock-in to a vendor. Open-core businesses hope you'll be willing to trade your freedom for tangible short-term benefits or even just for "shiny."

They stand to benefit massively from having you locked in; they want to trade your freedom for their profit. While open-core businesses truthfully say they are sustaining open source core software, their actual business has nothing to do with open source. It’s a bait-and-switch, wrapping the same old lock-in under the flag of open source and hoping you won't notice.

This is not just a philosophical game. "Software freedom" may sound abstract, but it is the system of thinking behind the very practical and tangible benefits that have drawn vast numbers of businesses to use open source. As I've written previously, the four freedoms (to use, study, modify and distribute the software without restriction) have created a vast market by enabling cost-savings and flexibility. A business model that cultivates a casual disregard for those liberties while pretending otherwise deserves to be challenged -- and it was.