Marc Fleury, who created the successful "professional open source" software company, JBoss, is also an advocate of "free software" licensing. Speaking at the time of Sun's decision to release Java under the GNU General Public License (GPL), he said: “The GPL is the best of both worlds because, Stallman's political convictions aside, the GPL creates a very strong notion of 'intellectual property'", an assessment that Richard Stallman, the creator of the GPL, would have balked at, "and at the same time, Sun can still monetize their virtual machine with dual licensing."

More contentiously Fleury claimed that "IBM reacted negatively to the Sun announcement" that Java would be released under the GPL "because IBM's approach to open source is what we call 'strip mining', which is to let the open source community do things - then IBM comes and packages them, and adds proprietary code, and markets the result - witness WebSphere - so they have this dual strategy of proprietary products and low-end open source."

Freedom as a principle

It could be said that the GPL came into existence to prevent strip mining of open source, which can be interpreted as the appropriation of free software code for proprietary gain with no intention of feeding code changes back to the community.

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