GigsVT (208848) writes "Knowledgetree, a formerly GPLed document management system, is now only available as a hosted service, with a hefty subscription fee. The former community site at http://www.knowledgetree.org/ is unreachable, and the project is no longer available on Sourceforge. An open source release from 2009 can still be obtained, but only if you fill out a sales contact form first. It seems that Knowledgetree has found the big loophole in the GPL: You can take all that community work closed, if you do it by changing into an SaaS model."
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