OpenJUMP (OJ) and the used software components distributed are licensed as follows. For more recent informations about licensing read the readme.txt file of the OJ distribution you are using.
OpenJUMP core & plugins/extensions
OpenJUMP is distributed under the GPL license. A description of this license can be found in the "gpl2_license.txt" file in the "licenses" folder or on http://www.gnu.org/licenses/gpl-2.0.html .
OpenJUMP uses the BATIK libraries to write svg format. The BATIK libraries are used under the terms of the APACHE license, which can be found in the "apache_license.txt" file in the "licenses" folder or on http://www.apache.org/licenses/LICENSE-2.0.html .
We use also a math library called JMath. JMath and its successor projects JMathTools (IO,Plot,Array) are distributed under BSD license, to be found in "jmathlicense.txt" in the "licenses" folder or on http://jmathtools.sourceforge.net/ .
Jython is distributed under Jython license that can be found in the file "jython_license.txt" in the "licenses" folder or on http://www.jython.org/ .