Note: Since this post was published in late 2013, RapidMiner has moved to a traditional open core business model, delivering both open source and commercial editions of the software. RapidMiner believes in the free as in beer nature of open source software and the mutual learning, innovation, and agility that results from the synergies of an extensible core and a thriving user community.
The commercial version of RapidMiner can be downloaded at https://rapidminer.com/get-started and you can download the source code for RapidMiner Open Core on Github.
With the news of Rapid-I now being RapidMiner we thought it would be helpful to reiterate that the core of RapidMiner stays open source. And exactly like for previous versions of RapidMiner, we extend this core and offer this extended functionality only to our customers. Following this approach, the commercial editions of RapidMiner 6 will better scale up for the analysis of larger data sets and offers more connectors to data sources. At the same time, RapidMiner will change its model to business source, which means that older versions of the software are available under a OSI-certified open source license while the latest version, although still open source for most parts of the product, will only be available as a trial version or under an commercial license.
With every new major version, the newest major version and its updates will be available under this business source license while the previous versions will be licensed under the AGPL v3 just as before. This business source approach offers many of the benefits of an open source model and we consider it superior to the open core model which we have been using so far since the open core model does actually not offer any of the advantages of an open source license to our customers.