We have all been speculating for around a year now on what Oracle's intentions are towards the open source projects it inherited from Sun. It has been fairly obvious to most that Oracle intended to make money from its open sources assets but exactly how and exactly what this means has been unclear.
There also have been plenty of examples of dissatisfaction with Oracle - the OpenOffice fork to become LibreOffice, the loss of OpenSolaris, the walkout of Apache from the JCP and so on. But until now there has been little of Oracle actually moving to make money out of open source.
The situation with Hudson is quite different. It is the first, but probably not the last attempt, that Oracle has made to take commercial control of an open source project. Oracle has tried to present the situation as it if was all perfectly reasonable.
It doesn't really matter what the software does but in case you are interested it is a continuous integration tool used with source control systems like CVS, Git and so on. The key fact is that Hudson was started as a "hobby" project by Kohsuke Kawaguchi while at Sun which promptly sponsored it and trademarked the name. And it is the trademark which gives Oracle the extra power.
By controlling the trademark Oracle can dictate what happens under the Hudson name - down to specifying what can or cannot be called Hudson. Basically what Oracle said to the developers working on the project was that they could add to the Hudson core and still call the result Hudson but if they were to change the code in the core then they could not.
Notice that Oracle hasn't the power to stop anyone from reusing the open source code - just what they call the end result.
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